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Post by sime66 on Dec 14, 2015 6:10:09 GMT
Everybody except me! I was looking at all sorts of charts on the Internet; I had the DOH moment after I'd gone to bed, that a 140 is 1.4mm and I'm making a 150 – obvious when you realise, but not worth getting out of bed to correct myself last night. It also occurred to me that you slipped in a clue about revs/2mm, which I didn't pick up on; 2,500 in 3rd is 28kph for mine, so I perhaps I could use that as my guide? - and probably I was 10kph over that. I'll get a set of little drill bits, I have a pin vice, but last night these little Dremel bits were what I could get my hands on to get the job progressing. Now I have the key to the numbering I'll be more precise than just-a-bit-bigger than my file! I haven't yet spent a lot of time at WOT; just the odd blast to see how it felt, and more recently, to have a look at the temperature. I didn't realise we still wanted spluttery either, but I do know that lean feels good, and I'm indoctrinated/converted into this getting this Pilot jetting right to avoid nasty surprises later, so that plug wasn't going to go unresolved. If it means going back to redo the Pilot after a bit of MJ tweaking, I don't mind at all – that's what this pre-2016 season period was going to be for in my mind; avoiding tears is what we're about. Afterthought/waffle, to help my understanding: This needing a bigger MJ is to do with me opening up the Transfers etc. isn't it? Just so I can picture it; I'm getting a big volume going through the opened-up inlet, transfers and exhaust, and I've got a big carb letting plenty of air through, so I need a bigger MJ because there's not enough fuel to get the ratio right? Using a smaller carb, or restricting the air with the filter would have just restricted the volume and made the inlet, transfer, exhaust opening work less-effective? Now, giving it the fuel the opened-up casings and barrel need (with a bigger MJ) is allowing the full potential of volume through at the right ratio and so is possibly making a bit more of a beast than was expected, but that's because of the work on casings and barrel earlier in the year – so all those sweary Dremel-days, and getting told to go back and do it again, were worth it! There's always something else to worry about: at what point, hopefully not at all for my mild tune, does the fuel tap/volume flow start to be a factor? That'll do; morning ponderings cleared from my mind – I'll do this MJ and report back as soon as I get a chance.......... Thanks again for the wise words.
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Post by pxguru on Dec 14, 2015 9:46:11 GMT
I am pretty sure that the 150 will make it all nice and black again and we can work back to a smaller MJ from there. There is a small chance you might need the 52/140 back in but you will soon know. Give it a run on the 150 MJ and show us a fully black plug!
You are generally right with what you said and what most write ups say in that, the 2 stroke engine is an air pump. The better the engine breaths the more air it pumps. And more air needs more fuel to keep the stoichiometric ratio at about 13:1, for a 2 stroke that doesn't blow up. So yours is pumping more air through your ports and is needing a bigger main jet than guessed. This is not such a bad thing, as when jetted in well it might possibly turn out to be nice and economical when at a steady cruise.
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Post by vespasco on Dec 14, 2015 19:19:17 GMT
Sorry H, i wont do it again! There s nothing wrong with a fugly ride, they usually have a lot more go in them and are a lot more fun too Firstly the temps.... I only have my ali pinasco to compare against really, which will run cooler being ali, but a quick burst and temps of 139°c.... Does that sound a little warm to anyone? Especially in this cooler weather? (With cht ring under plug i used to ride wot and temps were 230°f max) Im not saying it is too hot but it seems to tally up with your white-ish plug Im not saying that you'd need to but i ended up swapping back to the si24 on my ported pinasco, it just seemed to run better all round than the si26 but i didnt really play with it long enough to get perfect. (I ended up virtually destroying it by drilling excessively large feed holes) Have a retorque of the head and carb next time you there too. And definitely, you should still be running rich, bogging a little on the MJ at this stage. Running clean all the way to wot at this stage suggests its more on the slightly lean/ragged edge for max performance rather than richer/safe. Next time you ride, try pulling the choke out a little, or even fully, to enrichen things and note any change in temps, feel, colour change in plug. It may save you swapping jets and adjusting the mix screw and give you a clue as to what needs adjusting. If you feel the motor accelerating when you pull the choke on its definitely to lean. My gut instinct tells me to put he 52/140 back in , when it was richer, good plug colour and work the rest of the jets,or more precisely, the atomizer, to suit that. If it had a flat spot with the 52/140 the change of atomizer could alter that. Obviously we dont want you running round in circles but it gets like that sometimes! Like you say, youll likely be riding not much more than 1/2 throttle most of the time so richer idle/progression is a lot safer and i think, a lot more necessary, especially when easing off the throttle as you coast downhill at 60mph. I hope thats helped and thrown any spanners the works. (Get yourself an extra long , like 450mm long! screwdriver for the carb tweaking, you dont get any thumbs in the way or rubbing on the chassis and the mix screw is real easy to adjust) Stick at it It will come And remember the choke is there with some extra fuel for you to use
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Post by sime66 on Dec 14, 2015 19:56:30 GMT
I think we're agreed I'm too hot and too lean. We've I.D. a problem, and developing a plan of action to find cause and solution.........(as long as I've got a plan I'm happy really). I'm going to chuck my oversized MJ in just to confirm the problem and take it from there; if it means changing the Pilot again, so be it. The MJ will be tweaked again later anyway - gonna get back to a nice safe, dark plug for now. Although I mentioned the possibility of going to the 24 on the previous page, I do see why the 26 will hopefully be worth the extra time getting it just right. I have retorqued the head again on the weekend, and I'll do the carb again when I change the MJ, just to be sure. I'm still uneasy about how the cht ring is affecting my plug seal though (without crush-ring). I'm pretty sure this is jetting though, otherwise my starting/idling/riding would be dodgy too, and they're all lovely. Going round in circles at this stage really is OK with me; preferably still allowing me to use it with care, which I am. It's on my cribsheet that this stage would involve some back-tracking and tweaking: keep going round in circles till its done but Pilot/progression/MJ/Atomiser is the sequence to tinker... I've got just the tool for the mix screw - a long, thin screwdriver from my jigsaw - 10" is enough for anyone! I do like the get-out-of-jail other use for the choke; hadn't thought of using it for engine temp adjustments!! Genuinely, I'm pretty relaxed about it all - well I will be once I've got some colour back anyway - there's plenty of time to get it right, I can still use it for all I need this time of year, I'm not doing any harm, and I'm learning a bit more as I go through the procedure too. - No worries. (Any hint of dejection is only frustration with my lack of skill, not with the job at all; doing this engine has been a great experience, and this is an important part of the job - commissioning).
I've not been in long; I'll read this again better and ponder it overnight; make sure I haven't missed anything - things seem to seep into the noggin better after I've had a while to think them through a bit.
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Post by pxguru on Dec 15, 2015 3:48:34 GMT
I think even with all the new fangled gadgets the plug colour is still the most important. Once the plug colour is right then you can check the temperature that is. On a cast barrel with a totally safe carb set up, slow cruising around should be something like 120C and full WOT thrash for many miles 150C. You will get used to what is right for yours very quickly once its done. As Vespasco said ally barrels run much hotter on the outside without seize ups! The choke is a top tip. If you are ever unsure if its rich or weak, try a bit of choke and see what happens. Need to always be careful and not mix up the fine tuning with the core activity. Its very tempting sometimes but gets really confusing The SI26/26 will set up perfectly in the end. Once bigger than a 150 MJ then the SI is at its limit really, will still work but is outside of its range and will then be restricting performance as well as other issues. Once the drilled 150 MJ is in and known to be too big, then you will need at least a 142, 145 and 148 to play with. I guess you have these ordered already? If the 150 MJ doesn't make it run black then we have problems!
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Post by sime66 on Dec 15, 2015 12:47:22 GMT
Thanks chaps; I was a bit rushed last night and this morning, but had time to ponder a bit now.
Vespasco; I've had an evening to chew over your post, and there's a few things niggling me in it; probably due to my misunderstanding, but worth a mention to check either what you meant or my understanding of it. I know you're on your holidays, so none of this is important at all, but just thought I'd bring the wasps in my brain up for general clarification:
Does that sound a little warm to anyone? Especially in this cooler weather? I do think/agree that my temps are warm, but I think cooler weather is a red herring here. This subject keeps coming up, so maybe it's time to get it thrashed out and agreed: Colder air is denser; it has more oxygen for the volume, so it is leaner. Colder air will make the combustion hotter. It is true that the ambient temperature and the cooling air over the fins is cooler, but cold air leans the mix. There must be some sort of balance/point where one of those factors becomes more significant than the other. In any case it isn't particularly cold at the moment; it will get considerably colder and that will lean the mix and make the temps potentially higher, not cooler. - That's my understanding of it. - (When I seized a couple of years ago it was snowing).
My gut instinct tells me to put he 52/140 back in , when it was richer, good plug colour Isn't a 52/140 leaner than a 52/120? - same fuel, bigger air? It would have been leaner with the 52/140, and I didn't do progression plug chops with that Pilot jet because I had a flat spot setting up and low running. We quickly moved onto the 52/120; it might be that it needs looking at again, but it is leaner isn't it?
If it had a flat spot with the 52/140 the change of atomizer could alter that. As above, the flat spots with the 52/140 were at rev/slide situations where the MJ stack should not have been involved; It didn't stay in the carb long enough to do any testing. Given that, I'm a little confused why we're thinking about changing the atomiser to get the Progression circuit correct. I do realise I'm changing the MJ now, but that's just to pin point the cause of my problem, and has arisen, probably, because I wasn't just on Progression when I should have been.
Pxguru; my temps are not wildly high, but they are probably high – my running around temp was up to 123ºC (we had previously been happy to see 120ºC), and my WOT in 4th was 139ºC (I had previously recorded 125ºC at 8,000, brief WOT, in 3rd), and the progression was up to 108ºC too (I believe we had previously been happy with 100ºC, but I'm pretty sure now I wasn't just on Progression for that – higher than 28kph). The plug colour clearly needs sorting anyway – we are all agreed on that regardless of other data. I've put the 150(ish)MJ in this morning (and checked that there was fuel in the well and that the 140 wasn't blocked)- that's all I had time for this morning; I'll find time to have a ride round during the week, and fingers crossed, hopefully provide a blackened plug. I haven't ordered 142, 145, 148 yet; the Beedspeed 'Dellorto' ones appear to be Spaco, and they haven't yet confirmed whether they have stock anyway. The SIP ones are 'SIP Performance', so I'm unsure how they compare. Wasp doesn't list above 140. Does anyone know of a reliable source of Dellorto 'INC' Si jets over 140? (Do Dellorto make them?) Hopefully in the next day or so we'll have an idea of whether the MJ is the cause anyway – as soon as I've had a ride, by which time I hope to have found a source, or decided to go Spaco or SIP.
All the other possibilities, before I get that plug info back here, are a bit more than I have time to think about and get my head round at the moment; this last normal working week before holidays has gone a bit hectic, so I'm just going to concentrate on getting that MJ/plug info back to the forum before worrying about other stuff. I can envisage what the other 'problems' you mention might be, but I'm doubting it's anything serious, and am just deciding not to worry about that until I've done just my next job; I'll be back with the info soon.
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Post by henri on Dec 15, 2015 17:28:18 GMT
jets ,try dellorto (uk) direct , they do online sales if i remember right .an with the weird weather weve had this autumn/winter i'd be keeping a eye on pressure more than temp ,which has been warm . low pressure has opposite effect to low temp an would be richening the mix. i know you'll be reluctant ,but i'd be tempted to put the 24/24 back on by now , would be easier to jet on the main n atomiser , an would give a strong indication of where a 26/26 should be jetted . + 1mm on choke size =+10% on main ,so a 24/24's jetting + 20% should give safe ballpark jetting on a 26/26 out the box to fettle . H
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Post by sime66 on Dec 15, 2015 19:13:55 GMT
Thanks H; I had not thought about pressure, and it is an interesting point, and probably just as valid as temp, but I'm still not convinced that my disappointing change in plug colour is due to either of these – especially as I was in the middle of fiddling with my carb when it went from reassuring brown to the scary white. However, here's what I think I know about air pressure, which might be as right or wrong as my temperature understanding. In the S.W. We have been having slightly higher than average barometric pressure, giving mild, stormy weather – this is Plymouth:
High pressure = dense air = more oxygen = lean = more power = higher combustion temps. (think also cold air and sea level)
Low pressure = thin air = less oxygen = rich = less power = lower combustion temps. (think also warm air and altitude)
If anything the high pressure we have been having, and the warm temperatures are indeed acting opposite to each other, which to my mind makes them less significant to the quest for the cause of my white plug, and neither of them are extreme when compared with mid-Summer or mid-Winter. I know 'warm for time of year' does not equate to 'warm', but all I'm saying is not significantly warm or cold – or significantly high or low pressure compared to annual extremes.
I looked on Dellorto UK (Eurocarb?); they don't list above 140 either, so I've sent them an email to ask if they made them, stocked them, sold them. Thanks for the tip, I haven't considered them for parts before, just grabbing info – quite expensive though.
With the 24 carb thing; it was my early thought too (to cut down the air), but I'm not sure we've given the 26 a fair chance yet; it probably seems a long time on this bit because I'm only really plug-chopping on a Sunday morning, then coming back to discuss/ask advice, set-up in the week to chop again the following Sunday, so the process has taken a few weeks without much progress, but it isn't actually more than one of you chaps would have covered in a morning tinkering-thinking-tinkering. I'm not skilled, not familiar, not confident – but I am tenacious, and with the carb, and with the Pilot jetting (and probably the main and mixer too when we get to them), I am not yet sure that any of what I've done so far is reliable enough to dismiss the carb, jet etc without a bit more trialling/tweaking/testing/thinking. - In short, I see the benefits of the 26 when it's set up right, I believe with time it can be set up right, and I don't believe it's yet time to bin it for the 24. The 24 jetting + 20% theory is interesting, actually. I didn't have all the porting on my DR180 with the 24 carb, but I had a 120MJ (safely more than accurately jetted); the +20% would give me 144MJ on a 26. (or my home-made 150(ish)-special to be tested in the morning!!)
I was wondering what pxguru meant by 'Need to always be careful and not mix up the fine tuning with the core activity'; I'm beginning to think some of the bits we've been discussing here since my white plugs are not really so relevant to that basic sequence of core stages I'm working through, so I'm trying to keep replying to points raised, but concentrate my scoot-tweak-time on what I was intending to do, which has needed a diversion from the plan to sort this out to avoid tears, but not to get too bogged down in it, yet.
That'll do; just writing it out, so I don't spend all night with the brain-wasps again! I'm hoping to have an hour's ride round in the morning, hoping for some lower temps and spluttering a bit – and some colour in my plug. If I do get on it, I'll post up some results some time tomorrow....................
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Post by pxguru on Dec 16, 2015 4:15:07 GMT
Weather effect on jetting is more in my fine tuning category. When racing and running weak (more powerful) its really important to be on the safe side of the edge but weather effect is something like +/- 2% at most. I am sure yours will end up on double plus rich for the safest riding and weather will never be an issue. The reason its hard to find jets over 140 is because Dellorto think that's the limit of the carb. There are some bigger jets out there but not dellorto. I say it can go to 150 but will need drilling out of the carb MJ ducts and float needle like Vespasco did on his to support it. I can't believe yours will need much more than a 140, so you might possibly get away without the drilling but should do it anyway as a precaution, after the basic set up is done. I was really expecting you to end up about 135 or 138. The 150 should hopefully make it so rich it just about cuts out at WOT. Remember the fuel flow is all about area and not diameter. The 26/26 (really 25.5 but who cares?) is about 15% bigger than the 24/24, so the MJ should be about the same difference bigger. A 120 MJ in a 24/24 would be a 130 MJ in a 26/26. So anything over 130 is down to your tuning. If you have done it too well and the home made 150 doesn't make it run terrible at WOT (which it really will) then it's back to the 24/24 to restrict it, de-tune the barrel (new territory for me!) or fit a big boys carb Edit; I definately remember it was spluttering at WOT before. So there are two options. Running it in has increased the performance more than it usually does or the 55/160 pilot plus 140 MJ was keeping WOT over rich but the 52/120 plus 140 MJ was weak at WOT. Seems a bit too much of a fine line. Did the WOT spluttering stop long before the pilot was changed?
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Post by sime66 on Dec 16, 2015 7:24:11 GMT
By recollection, though I will read back later to check, I have never had spluttering at WOT. When first running in, I was deliberately rich with what we thought would be oversized MJ, open mix screw and 3%; rough running, dark plugs, no idling etc. - There was no WOT riding at this stage After 200 miles we went over to 2%, set up the carb screws to get it idling, there was a period of swapping Pilot jet, adjusting mix and idle screws. Low running to check for lack of rough running, flat spots, and eventually plug chopping. - There was no WOT riding at this stage either. Four things changed, I think this is the order: The 55/160 was changed to 52/140 (which we didn't spend time on), and then the 52/120. We gave it it's frst blast to WOT in 3rd (8,000, 90kph, 123ºC; I'm sure there's a plug for that; I'll look later). There was no spluttering to WOT or at WOT. We decided that my Progression plug chops were too slow or too short, so I made them faster (from 1-2mm), and on a longer route with adequate warming up first. You suggested I should be using new plugs. Then with the 52/120, which was giving me the best low running, and the best Idle-Rev-Idle and slow Idle with Idle and mix screw combination, I did more Progression plug chops. It was these plug chops that were white and giving high temps. During the warming up before a repeat of those same tests on Sunday just past, after a tweak which hopefully had ensured I'd got it set-up right again, I opened it up to WOT for a brief time and noted 139ºC. There was no spluttering to WOT or at WOT. Later you asked if it spluttered at WOT, and I said that it didn't splutter at any stage any more (since those first carb tweaks, Pilot changes and going to 2% in fact). It never spluttered at WOT before because I was never riding at WOT when it was still spluttering because that is before whichever changes stopped it spluttering.
I'm not thinking about big carbs or detuning; I know lean feels good, but this really does feel good to me, certainly not on the safe-side where I want to be, but I'm sure a bit of patience will see this jetting right on the 26 carb. I really don't think we've given it a fair chance; I'll re-emphasise; it's taking a long time because of the way I'm doing it, because I'm always checking at every step, because I'm pretty unsure of what I'm doing at each stage, because it is all new to me – let it take the time needed. My gut feeling is that we're reaching out in all direction for possible causes and solutions before really identifying the cause properly, so I'm focussed on just doing that for now. If I'm white and hot again today, I will not be getting my spanners out, out be stopping to have a proper think about it, which this week hasn't really allowed me yet.
Anyway, in the next couple of hours or so I'll be back with some photos and temps. Lets hope there weren't too many Christmas parties last night, and this morning's bleary-eyed morning commuters mainly have a legal blood-alcohol level; if you don't hear back by lunchtime, I'm probably in Derriford Hospital....................
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Post by pxguru on Dec 16, 2015 9:46:53 GMT
It will be a chilly ride but important information! Fingers crossed for nice and sooty black Important Lesson No.1 - It should have had a main jet that made it mildly splutter from near WOT since the first time it started until now.You've had a lucky escape. I guess that's the limitation of doing things like this using a forum.
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Post by sime66 on Dec 16, 2015 10:00:25 GMT
Weather conditions:Precip: Overcast (100%), heavy drizzle Pressure: 1017mb Temp: 12ºC Wind: SW – 15 knots, gusting 40 knots. (That's what it says, but I felt a pretty constant high SW) Running temps – as best I can recall:Low in 3rd – 98ºC (in traffic) – Noticed nothing to concern me. Low speed cruising 4th – 118ºC± (variable with hills and wind) High speed cruising 4th - 127ºC± (variable with hills and wind) - Basically around the 120ºC, depending on whether I'm pushing or not. – Noticed nothing to concern me. Progression speed temp high 95ºCs (2mm, 2,500, 30kph, 3rd) – was108ºC before – Noticed nothing to concern me. WOT - uphill into wind 139ºC – going to 144ºC after throttling off, but dropping to normal quickly. High? [There's nothing really scary there; there's a slight improvement lower than WOT, but WOT is still probably higher than it should be] Pulling choke out whilst cruising (112ºC) gave just a slight feeling like throttling off very slightly, and pushing it in made it pick up again – nothing major. No WOT, or up to WOT spluttering; maybe just spluttering at low speed/revs, but that might just have been whilst cold. Possibly didn't feel quite as quick – didn't notice precise high speeds much as was concentrating on temps, and not ideal anyway because of traffic and wet &windy (couldn't even hear engine). Most significantly – Still got a white plug; I only did 30km, mainly cruising once out of town, and one run holding it at WOT longer than before. Several other runs at different speeds and gears; uphill/downhill, headwind/tailwind (as above). I came back early because I was not spluttering and because the temps weren't significantly lower, also visibility, wind and traffic were horrible, and because I was running out of fuel and didn't have my wallet.
I can do all the other photos, but I think, this time, just the one photo will suffice to confirm the situation – there's no ring at base of cone. (I've kept the plug if more details are needed).
I'm not making any quick decisions. I think I'll fill-'er-up and have a round-town ride without CHT ring (probably not until Saturday morning now); temps won't go silly just doing that, and maybe I'll get some colour and identify CHT ring/plug leak as culprit. I'll also check my idle isn't blocked, and maybe change it back to where we were getting OK plug colour; safe for the holidays and just treat it as the final running-in miles, but I'll think about all of that. I forgot to check the carb torque the other day, but I am sure I'd be noticing it if that was the cause; I'll do that too, just to remove the possibility. So I'm just pausing for thought for a few days; this isn't benefiting from stealing an hour here and there and rushing the testing or conclusions, but it does seem that something, other than the MJ, is not right.
Just for the record, this is the difference between the 140 and my home-made 150 (maybe not significantly bigger? - I could make it bigger, or we could say it's nothing to do with MJ and put 140 back in - duno):
I'm out of time today, but I'll read and cogitate any comments this evening....................
(it's all part of the fun chaps - as long as it don't end in tears!)
*** I notice your post, pxguru, but I'm going to post mine as it is because there's no time left to edit it. I do notice your lucky escapeǂǂ comment though, so maybe I'll revise my plans, but I'll leave it as it is until this evening and see what response my results give.
(ǂǂ - take note, those who want to put a new engine in, and ride-it-like-you-stole-it!!)
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Post by sime66 on Dec 16, 2015 12:56:22 GMT
I did a bit of reading-back over lunch, Facts, figures, dates gathered from previous pages:On 8th Nov I repeatedly recorded 147ºC , 80 kph; didn't record what gear or whether WOT, but I'd say a quick non-WOT blast in 3rd. On 15th Nov, I recorded that I had still done no WOT riding, but we were all keen that I have a bash. This is when I did my strobing and Idle-Rev-Idle stuff before doing a quick WOT in 3rd: On 22nd Nov I did a quick WOT in 3rd: still on 55/160, 90 kph, 8,000 & 125ºC (short WOT only; just to get to 90kph). On 27th Nov, I showed a nice brown (not a plug chop) plug. On 28th Nov, I showed a Progression plug chop that was still brown but we decided I needed to go from 1mm to 2mm. On 29th Nov ***, I showed a Progression plug chop at 2mm (max temp 102ºC) that was possibly not quite rich enough on progression; it was suggested I use new plugs for chopping, and try the 52/140. which proved to be boggy, and; On 1st Dec, I changed to the 52/120. On 2nd Dec, I got a much better Idle-Rev-Idle, slow Idle and smooth low speed/rev running; all ready for a Progression plug chop. On 6th Dec, I recorded the first white plug on Progression plug chop, with the 52/120, and 'Over 100ºC' – not very precise! On13th Dec, after a mix and idle tweak with the 52/120, I still got a white plug, but recorded 108ºC on the 2mm Progression plug chop. On 16th Dec (today) with a home-made 150(ish) MJ I recorded the numbers and plug in my post directly above this. (Still hot, still white). Confession time:***I have one slight embarrassing confession from this day (29th Nov), which I didn't mention at the time, but just might be relevant now: The scoot ended up on it's side when I was unseated at the end of a plug chop (at very slow speed), when I inadvertently applied the front brake on a wet road, after missing the ignition switch and grabbing back at the handlebars, when I had a car up my rear that had pulled out behind me when I was slowing. There was absolutely no damage to any external part of the scooter (couldn't even find a scrape), which started straight away, and ran exactly as before; I just recorded it on the forum as “I had a bit of bother on wet and windy roads on Sunday, just on the progression chops”. It seemed insignificant, but it dawned on me this morning that it might be relevant, so I went back to check the dates to see where it fitted in with the first white plug. It was just before that, so maybe I did cause myself a leak somewhere? I still don't think it was significant, but it would be wrong not to mention it now under the circumstances. - I Hope I haven't broken it................ ǂǂ Rather than a lucky escape, I'd like to think the methodical approach and care has proven to have been worthwhile in showing a problem before it manifested itself in a more dramatic way!! (Unless I have broken it, in which case serves me right for riding like a Nancy, which wasn't allowed for in my crib sheet, so the method's still good anyway). That's where I'm at – warts and all! BTW: Dellorto do not make Si push-in above 140 – that's from the horses mouth (Matt Cooper). Beedspeed do have them in stock; not sure if I'm going to be needing them now though – I've got the full Dellorto set up to 140, and maybe the big MJ was a red herring.
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Post by pxguru on Dec 16, 2015 12:56:39 GMT
This is a little disapointing. You knew I expected this to be mega rich on the 150 jet. I expected it to be rich on the 140 jet! There is something wrong. I don't think the spark plug could do this even if you left it loose. Ok ideas needed.
1. Take the MJ out completely and put the BE3 back in without one. How does it ride now? Should flood out very badly, as soon as it's over a few thousand revs. 2. Whats the flow rate on your fuel tap? Could be just a dribble. 3. Might be struggling with float level and need the filter hole drilled out. 4. Your 26/26 could have something blocking the jet way from the float bowl to MJ. Drill this out anyway. I think 2mm is the going rate.
Stop riding it anywhere far until this is sorted and you get it flooding. Even if it doesn't seize it could do something ugly like flat top the piston.
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Post by sime66 on Dec 16, 2015 14:27:42 GMT
Thanks, pxg; we posted at about the same time, but I don't think it matters. Yours is very much about fuel, so I'll go through the system from tap to jet to outlet and check everything is clear and doing what it should. I'll start with a run with no MJ, if I'm not flooding I'll check the flow (tap and fuel line), make sure float and needle are doing their job, if that's all OK I'll have the carb out for checking, drilling etc. (I know the drilling areas you mean, vespasco did a thread (with some words of caution); I'll get familiar with that and do it. It's all good; have a plan, will get on with it........... (Chaps, there'll be no M.D. wavs or graphs to play with on Boxing Day )
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al
1st Class Ticket
Posts: 50
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Post by al on Dec 16, 2015 14:54:41 GMT
Don't half give you a twitchy arse riding on a lean looking plug don't it.My 200 runs a 150 jet and still looks lean.I gave up on riding at 60 for long periods.I now constantly scan my chat gauge for any thing over 125C.Keep up the updates I've enjoyed them bud.
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Post by sime66 on Dec 16, 2015 15:17:43 GMT
Cheers Al. Not ideal is it; she'll be right, though. Going to check out the fuel all the way through – bet I end up with drilling out the carb and/or fast-flow tap. I'm remarkably chilled about it all really. (I suppose the job was due a nasty surprise – going too well).
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al
1st Class Ticket
Posts: 50
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Post by al on Dec 16, 2015 16:01:06 GMT
I fitted a SIP fast flow thinking that might be the problem but was not so.Plus the tap does not work the warning light for some reason.
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Post by sime66 on Dec 16, 2015 16:14:50 GMT
I've not really thought much about it before; I know we've discussed and pretty much decided the BGM one is better, and there is a wired one (low level warning) and a normal one: www.scooter-center.com/en/classic/search?query=bgm+fast+flow+tapI guess as my EFL speedo has fuel gauge and warning light (from fuel sender in tank), I won't want the wired one and won't have that problem. Truth is neither my gauge or warning lamp have worked for years; it's on my fix-it-one-day list. Anyway, there's a few things to check out before I'm buying a new tap. There's a thread on here fairly recently about opening up some carb channels (fuel inlet to filter and from float chamber to MJ well); I'll post a link here when I dig it out – I need to read it again myself......... Here's the link; it's vespasco's - he's alright if you keep an eye on him: vespa.proboards.com/thread/4947/si-carb-modifications-considerations-celebrations(Sorry vespasco; gone a bit end-of-term frivolity again )
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Post by henri on Dec 16, 2015 17:04:13 GMT
if you look here ,http://www.setup-largeframe.de.vu/ . German Scooter Forum , theres specs n set ups for around 400 177cc scoots , only found 3 so far using a 26/26 ,an there all short stroke px80's ,an dont state there mains .in the 180cc section theres 10 entrys ,1 for a 26mil carb with 128 main jet . have a look through ,most seem to be either 24/24's with mains in mid 120's or big-boy 28mm+ carbs running 140+ mains .an reeds/cut cranks/full-circles etc. a 125 plus 20%=150 , or +15% = 143 ,both bigger than dell does , so maybe why most run 24/24 or jump to different manifolds. an if i remember vespacos carb experiments ,he never got engine un lumpy til swapping back to a stock/undrilled carb , an he had a cosa float top to start with .H
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Post by sime66 on Dec 16, 2015 17:41:00 GMT
Maybe there's something in it, H (keeping the MJ under 140 by using the 24). I've got a couple of tests to do before taking the carb out (the no MJ run, and checking the fuel flow), but if I get to the stage of taking it out to play, maybe I'll bung the 24 on just to see (just checked my box of goodies; I have MJ 120, 22, 25, 27, 28 in the 120s – one of the larger of those in my Si24 might get me colour back - or using pxg's post earlier, I have 130, 32, 35 & 38 - must be something there we can make work). After we'd just been talking about fast flow taps I remembered the Cosa 5.2mm float top, and started having a look around, started looking on Ebay.de too, but on Scootercentre I found this: www.scooter-center.com/en/product/7672624/Float+chamber+top+Vespa+Cosa+DELLORTO+Dellorto+SI2020+SI2424+52mm+float+needle?meta=...….which seems to say that top fits an Si 20 & 24, not a 26 (not sure if that's correct), but if that's so then it would be the 5.2mm needle float top on an Si 24. Anyway, this is all after I've done a few more tests on the fuel on the scoot whilst still all together. We all seem to be leaning towards fuel, rather than air leaks though, so that's good. Thanks for the GSF link too; I remembered you'd mentioned it before, but didn't know where to look for it; that'll be worth a bit of a scour-through. As I say, though – I'll do the other couple of tests before jumping too far ahead............ Not had a tune for a while........... The Specials – Pearls Cafe – It's all a load of Carb-ollocks:
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Post by pxguru on Dec 17, 2015 2:55:52 GMT
Too early to give up on the 26/26, do the tests on it first if it still runs without a main jet then it is surely a fuel delivery problem. One thing I keep thinking of is that when you just ran it on the 150 MJ, pulling out the choke had hardly any effect. Should have been running rich already then flooded out totally with the choke. If the float bowl was already ow level then the choke wouldn't work either. It could just be something simple like a kink in your fuel pipe under the tank. Wouldn't that be easy? My feeling is that the float level is not being maintained. Should be possible for you to find and fix. It is funny how the plug had colour on the 140 and 55/160 before it fell over! Yet the 150 MJ couldn't bring it back. Keep in mind yours is only touring tuned. A 150 main jet in the 26/26 should be way over.
Edit; silly question, you did put on a non-autolube carb box didnt you?
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Post by sime66 on Dec 17, 2015 5:19:29 GMT
This might read a bit disjointed because I've got lots of thoughts that haven't really organised themselves yet, so I'll start with the important stuff:
Absolutely, the tests first: running without MJ, and timing fuel flow – I've found some figures to compare with. Doing that will check out my fuel line as well (I have a new one to fit anyway), I'll check my cap too. My mind is tuned in to fully checking through the fuel system as priority. I am a little doubtful about how it can be riding so splendidly, and be so hot/lean from fuel starvation and why it isn't cutting out or struggling. I know lean feels good, but does fuel starvation? (is it hot? - from those figures yesterday – it's been those temps and higher since 8th Nov). I'm also a wondering why spluttering at low revs for kidda was lean, and I'm trying to get mine spluttering to show it's over-rich. I'm also wondering why I haven't got any fuel starvation symptoms (like the WOT cutting out) like vespasco had when he was playing with carbs and taps. (I'm wondering a lot of things, but I'll leave those to the end to keep my reply on track). Yes, I've got a non-autolube carb box Yes, the unceremonious, riderless, horizontal-parking of the scooter, whilst it seemed insignificant at the time, does tie in exactly with the first white plug, (maybe I just got a bit of fuel tank clinker in my pipe), but the first white plug also ties in with first using new plugs, so maybe it was already going unnoticed. The white plug also ties in with at least four other factors, which I listed yesterday. I wanted to mention the incident, but was wary that it might lead to dubious theories, when a more systematic investigation will probably find the cause sooner. In my mind – and at the time I thought it was what we wanted – the running-in rough/spluttery running ended after 200 miles, when I went to 2%, wound my mix in and set my idle to get it to tick-over so I could play with the Pilot jet, and started to tweak/ride/change the Pilot jet. That's when I got it smooth through the full rev range I was using, BUT I was not at WOT then. Those first Progression plug chops and general plug inspections also showed decent plug colours. That was all on the 55/160 (the leanest Pilot I've tried?), It was as I tweaked and changed that I got a white plug (As above that's also when I started using new plugs and the time of the incident). 22nd Nov was my first WOT; there's plug photos from 27th and a Progression plug chop from 28th – both on 55/160, both showing colour (but on cleaned, old plugs).
After I've done those tests, my next thoughts are to get the set-up back to a known safe point, wherever that was. I know what I changed, and the rough order I changed them, so should be able to get it back to it. I would like to reach a pause-point by the end of the weekend where I can use it safely over Christmas – preferably without resorting to swapping the carbs. There are also some slight temporary air-restricting things I could do, but by that stage we're admitting there's a problem with the carb itself; I could put an un-drilled air filter, or slightly obstruct the air duct for example; I'm sure there's other ways of restricting air; conventional and imaginative. I suspect you won't like that idea, and I also suspect you will think that those are not enough to be giving me a white plug. I also want to do a run without the CHT ring, because, despite what you said yesterday, I'm not going to stop doubting it until I've tried it. All the time the theories are external to the engine, I'm pretty relaxed about it, and fairly optimistic it'll be something I can find and fix without too much palaver; the white plug has to be sorted though.
If I am taking the carb off to check-out/open-out the channels (H, I'm aware some of vespasco's stuff was unsuccessful – he's edited his post to acknowledge that and highlight the problems), then maybe there's a temporary safe Si24 set-up I could put on over Christmas – that depends on whether it's a tap/fuel line problem, or a carb problem, or something else.
Without any poor running/fuel starvation etc. symptoms, all I can do is go through the systems until find a cause. I'll check nothing is dislodged or loose from the incident as I go through the scooter, just to be sure.
I need to do those first couple of tests, and I need to get my thoughts in order, and I need to get a plan of action for the next few days, but by Saturday, I need to be leaving it at a point where I can check it Sunday and ride it safely throughout the following two weeks with only keeping an eye on my temps and checking my plug. Not long or fast journeys, but to be able to get about in smart clobber without wondering if I'm going to need a rucksack full of tools, or how to get 2-stroke out of Mohair!
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Post by sime66 on Dec 17, 2015 8:51:57 GMT
…..quick update. This morning, I have taken out MJ and replaced stack. Have checked Pilot wasn't blocked. Both jets were wet 24 hours after riding, so it isn't a bone-dry, drained scenario. The carb was not loose at all either, and bolts are tight. I'll do a spluttery, dark-plug (please) ride tomorrow – plenty-enough revs to be sure, and report back then. I haven't got time to ride today, and I'm not playing with the tank until that's done. I'll drain what litle there is left, measure and time it as a low tank level test, and then do a high tank level test (I filled my 5L can up this morning). I'll also work out the level of tap relative to banjo, unless anyone knows it. When I'm playing with jets I always stuff the venturi with a sandwich bag. After I'd got rubber box-seal, filter and lid on, checked throttle was free-moving, and found the thread on those two bustard top screws, I did my stock-take of tools and parts whilst packing up, and found that it would probably be best to do a re-run of the job, but this time TAKE THE BLEEDIN' BAG OUT!! - I really must stop rushing about.
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Post by pxguru on Dec 17, 2015 9:14:20 GMT
There is no doubt in my mind that the 26/26 can be set up. The one now on my tourer was before on my early tune Polossi a few years ago. It was running a 165 main jet (1.6mm drill loose fit) 55/100 pilot, drilled jet ways and a drilled BE3. Ran perfectly well with an ok normal plug colour. Didnt have a fuel pump or fast flow tap either (has a fuel pump now but still only standard tap). Was smooth from tickover to 9000 rpm. Never blew up, even though I didn't have a CHT gauge. Carb was clearly too small. I only planned to tune it a bit. look where it ended up!
Yours is less tuned, smaller bore and no expansion pipe. A 150 main jet should be plenty and some.
Not sure what to hope for with your test. If it runs terribly it just needs carb work. If it runs the same there is a delivery issue. Which is easier to fix?
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Post by pxguru on Dec 17, 2015 13:09:13 GMT
You should try it to rule it out but sucking in air from the plug thread would be difficult. Everytime the piston goes down there is an explosion on top of it!
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Post by sime66 on Dec 17, 2015 14:59:13 GMT
I couldn't leave it alone this afternoon, so nipped out for a blast up the lane with no MJ: 1) We have a really spluttery ride 2) We have a black and oily plug (Wet not sooty; is that significant, or just because I din't get it hot enough to burn it?) (Got to think it through now, but this makes me happy because we are barking up the right tree!) This is running up and down the lane with no MJ:
So, after that I changed the plug, put the 150(ish) back in, and an undrilled air filter (as a slight restriction – easy to go back if not wise), and went for a quick WOT blast – only very quick, but a couple of quick with WOT in 3rd straight into WOT in 4th , up to about 110kph on my speedo (about 90kph - no GPS today) and the max temp was 102ºC. I know that doesn't count as a proper test, and the only spluttering was in mid-revs, but it's probably safer than it was yesterday (with the filter), there's even a slight hint of light brown on the plug, and I can probably give it a bit of a proper test early tomorrow. I did a quick idle-rev-idle, and just turned the idle screw in a ¼-turn because it was cutting out as the revs dropped from full throttle – just carried on dropping past idle, farted for a bit and stopped, so I just upped it a bit to stop that (left the mix screw where it was).
I've only really done the filter because it leaves it less lean than before; I'm not thinking of it as a fix – I want to leave it usable, safely for local short trips.
I think we're going to be moving on to drilling the float well to MJ channel to 2mm, but I'll take a moment to let the options sink in, and any advice on that – still waiting for little drill set anyway. **thinking that through a bit, if you think float level might be the problem, then the filter inlet will need doing too, so I bet I end up with tank out and checking flow-rate anyway, to find the bottle-neck.
I could open my 150 up a bit, or make another bigger one. - I know, we don't know why it seems to want it.
I'm hoping that means the tank can stay put for now - at least for now.
I think I'm going to post this, have a think, and probably come back and edit it once I've had time to get it straight in my mind, but we're narrowing it down now. I'll try to photo the second plug; I think the camera will bleach it, and it was only a short run, but there is definitely a bit of colour instead of the dazzling white I've been seeing:
This is only to show that there is a slight hint of colour - I know it's still no good:
Now I've got over the rush to post some progress; I did read yours earlier, and first thought how you were richer in Pilot and Main (for good reason) and there must be some reason my MJ that we're fairly certain is too big, is not behaving like it's too big – no plug colour, too hot, not spluttery; I think we're still on that question, but this little test should give us some clues, and discount some other theories.
It's progress; a bit of an understanding of the problem, and a bit of a plan to sort it – she'll be right........
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Post by henri on Dec 17, 2015 15:47:57 GMT
not a proper chop but more encouraging ,most of the stuff on german site is oldish so i'm guessing youve run into the brickwall those lads did when 140 was biggest dell did ,thats why they ran 24/24's or much bigger .nowadays i think sip maybe or bgm do larger jets .better to buy if possible ,as drilling your own really needs to be done in a jig/pillar drill rather than by hand .so hole is at 90 degrees an not ovalled/inaccurate by drill moving about . when ya get your 26/26 sorted (note the "when" not if) an 24's not going back on for sure we'll have a deal on a 128/130/132 jet if not being used .vulturish i know ,but its the early vulture gets the eyeballs , H
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Post by henri on Dec 17, 2015 15:55:52 GMT
yep ,http://www.sip-scootershop.com/en/products/jet+si+dellortosip+84+_40268400 , probably already found this 1 , dell mains on sip.scroll down to choose size manually ,sip performance jets 142 to 165 , £5 each tho but with postage getting expensive ,then anybody ever told you tunings cheap i hope ya ignored the fool . H
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Post by henri on Dec 17, 2015 15:58:51 GMT
bingo ,http://jet200.com/catalog/product_info.php?products_id=2136 , bgm jet kit 142-165 $15 ,european seller so postage shouldnt be too much . H oops not eu seller ,but states jet kits in europe ,wonder were ,the hunt is on . H
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