|
|
Post by vespasco on Dec 15, 2014 19:18:13 GMT
I recorded some more Dyno runs yesterday (that thread will be updated soon-ish) and I ended up advancing ignition by about 1.5°, so in my head (as i didnt measure it), it was about @ about 20.5° BTDC. It then got dark/windy so i ran out of time to carry on tweaking. Today... I finally got round to actually measuring the timing - 17.5° BTDC!?! WTF? That was after i d already advanced it by around 1.5° ! Below is a pic of the pick up i took a few weeks ago...i suspect its just the same now. Its possible that it got knocked while i was rebuilding it?? And then worn down I marked the inside of the flywheel and noticed it was indeed rubbing on the flywheel. I guess that would account for the retarded ignition!?!! Hopefully this simple problem will be the cause of my low rpm!! Ive since strobed and measured with timing disc. Now set @ 19° I kicked it over... and already, its a much nicer, even running motor. I could hear that straight away. Ive not had a chance to take it for a spin as yet but im expecting a vast improvement! Heres the actual pick up  Worth replacing? or fix it better, so it doesn't move, then set the ignition again? |
|
|
|
Post by sbwnik on Dec 15, 2014 21:36:11 GMT
They generally look pretty much like that pretty quickly. Are you sure you were turning the stator the right way?
|
|
|
|
Post by pxguru on Dec 16, 2014 3:51:05 GMT
Will look forward to seeing the MD runs. Going to confuse the issue slightly with multiple variables (packer and timing) but it will be the shape that is important  That timing was way to low for performance. On your set up I would say you could go a few degrees more without any worry. Some Pinasco 225s can run standard 200 timing. Just listen out for detonation at high rpm and check the plug for electrode rounding/melting after a while. This might really help your rpm like you say. We know the blowdown is under minimum but if it starts to go ok for you, then having low blowdown won't do any harm, will just be more economical/slow After you have sorted it could put some tippex on the stator pick up where it was touching. It will help next time you take the flywheel off to see if its still rubbing. |
|
|
|
Post by henri on Dec 16, 2014 9:36:45 GMT
i'd leave the pick up for now an maybe get another in store an replace in future when convenient,as its still working its not worth taking the flywheel off again , just keep an ear out for any random firings/variable timing at higher revs .
an i think i'd leave the timing at 19 aswell, as pxguru says you could get a tiny advantage in power by advancing slightly but for me the higher risk of pinking an damage outweighs the gains ,aswell as looking for rounding/erosion of the plug get a magnifying glass an inspect it for deposits of ali balls ,tiny little bits of eroded piston crown ,they will show up before plug damage becomes obvious ,
which brand an type of fuel do you normally use ,as this can be a factor in pinking ,H
|
|
|
|
Post by vespasco on Dec 16, 2014 10:41:35 GMT
Im still looking at the results of the Dynos but as mentioned, it was windy!! I took a few dyno runs after each adjustment. 1@ a time! But it was getting too noisy n windy to get accurate results. Ill post them when i get a moment if i think theyre worth it. First impressions, same curve! I knew it was not accelerating as it used to and i knew there was room to advance timing more, i just ran out of time and i couldnt hear if it was pinging anyway as it was too windy. I aim to do the same as the first time i built this motor ... Advance so much that it pings then retard a little until it stops!! Which was @ 19* previously. But i need a quite road with no wind to do all that. Dont worry h, it will be a ping free pinasco before ive finished tweaking. No wonder its been sluggish .. The pick up must have slipped / moved on the stator and as such this retarded the timing. It would only take a tiny knock for the pick up to slip round 1/2mm , exaggerating the actual degrees. Thats my guess. To check if it was rubbing i marked the inside of the flywheel with a sharpie pen. Its a little less messy than tippex Altho' i did use tippex to mark the ignition timing on flywheel Ive just ordered a new pick up, mainly because the pick up has nothing left to fix the red wire to and had already been repaired. Otherwise id still use this one. Ive always used Shell premium, locally available, i think if i set the ignition up for that fuel it will be ok. Although id prefer to use Esso or BP but their garages are miles away. But always premium!! |
|
me
High Number
Posts: 105
|
Post by me on Dec 16, 2014 22:41:59 GMT
Are you getting your advance and retard mixed up - clockwise turn of the stator retards the timming - closer to TDC - anti clockwise advances the timming away from TDC.
Looking at the marks on the stator the A mark is linning up with the mark on the block witch is noramlly 23 degrees as per 200.
there seems to be lots of scratching on the crank taper - how's the fly bearing - has it any play - or should i say more than normal. is the woodruff key slot ok? there is a small amount of slop between the key and the flywheel slot which can also effect the timming slightly.
With higher reving engines they will always benifit from running retarded timming - for standard 8000ish revers i'd stay standard.
Whats the spec of the engine?
|
|
|
|
Post by henri on Dec 17, 2014 9:03:20 GMT
the rally mark is for 24 degrees if i'm remembering right ,an the angle of photo is making it hard to judge ,but i'd say its just advanced a tad from the A mark, but as your strobing the timing trust the results from that ,the marks can be out by 1/2-1 degree ,more if your using ones on the fly-cover .
the real test is 2/3rds throttle up a slight grade an listening ,an sticking with the same grade/make of fuel to be safe , H
|
|
|
|
Post by vespasco on Dec 17, 2014 12:01:30 GMT
Im defo turning the stator the correct way!! Ive measured and strobed it too! The stator markings - this is the problem! Although the stator marks show it at 23°ish the strobe was 19°!! My recent engine builds were with stator on my old marks (@ 19°} Yet when i strobed it AFTER ADVANCING ABOUT 1.5° - 2° it only measured @17.5°!!! So it must have only been at around 15° btdc!!?? (No i didnt turn it the wrong way)! This is the point of this thread! But why like this?? Possibly because.......The pick up looks like its slipped/retarded itself. The flywheel could be slightly loose on the crank taper - the photo does indeed look like the taper is marked/scratched..ill double check that when i slip off the flywheel next . Ill show another pic of the taper too when i can find it....as there is a rust mark on the taper,,,which also shows signs of it slipping?  ?!!!! Fly bearng is new-ish. Engine spec is as per my signature. Pretty much stock px200e/cosa in p200 cases, with pinasco 225 (60mm stroker) n sip road. (all fitted into a Rally 200) It used to be great, for years - in 4th gear it would accelerate from 30 - 70mph pretty easy/quick.... Now it wont even reach 70mph! Since rebuild, using same spec etc, its very different. Upto now ive found the only/ main difference is the timng...too retarded.. Its now set @ 19° (strobed) - but i havent actually ridden it anywhere to see how it runs!! Strobed at 19° = stator timing mark A @ 23° !!!! |
|
|
|
Post by pxguru on Dec 17, 2014 18:13:35 GMT
something to think about for when its running right. I have my timing strobed to 26 degrees on the stator and using a programable CDI (Kheper) to reduce it. Makes changing the timing really quick. USB, laptop, click, wait 5 seconds  This way it is possible to have it all. The software allows the timing to be set on a curve against rpm. At the moment I run mine at 26 degrees up to about 4000rpm then on a curve to reduce it and flatten off at 8000rpm |
|
|
|
Post by vespasco on Dec 17, 2014 20:00:00 GMT
Ooooohh! Programmable! I like the sound of that! Me is doing a search! Ive heard of these timing gadgets. Im reluctant simply because i dont really like added 'extras' when its running fine. I like to keep things as simple as possible...but time 4 action??! Its not running fine and if they are reliable then id certainly consider one. Are they reliable? ...searching.... As for a plan.... I'll update another thread for that one *Edit; Heres a link to the kheper sites.google.com/site/kheperignitioncopy/And i found this too.... www.scootrally.com/phpBB3/viewtopic.php?t=2496&p=27346And a mk3 version coming soon!? How long have you been using yours guru ji? Any problems? How does it handle getting condensated in this colder weather? |
|
|
|
Post by henri on Dec 18, 2014 9:11:36 GMT
aswell as the programable cdi's theres a couple of piggy-back type units you can fit on a cdi an have pre-set curves at the click of a switch ,there was a article in scootering a few months back ,i'll see if i can find it .but from memory the basic 1 had 4 or 6 pre-sets an was about 65 quid, the better one was £115 an had 2 switches ,1 marked A to F an 1 marked 1-10 ,giving loads more pre-sets .
there made particular for scoots an are sealed units so should handle the weather ,but i'm guessing any condensation in the usb port will give probs when re-programming ,
an thats a weird one on ya timing marks n actual timing , maybe time to get a oversize woodruff key an file it to be a tight fit to help locate n fix the flywheel in one place ,wont help if theres too much slack on the tapers ,if you decide to lapp them in go very lightly as proper tapers are a interference fit sort of thing ,not perfectly matched,H
|
|
?!!!!