Running in plug after 215 miles

[sime66]

I haven’t done any plug chops yet, but this is my plug after 215 miles running in. It’s pretty oily isn’t it? Certainly more fouled than before, but I haven’t done any running in before, so don’t know what to expect.
It’s a PX177, SI20.20D, sito+, B7HS, 110 main jet (was a 108 before seize and new piston).
I do not know if this is of any value yet; some say regular plug chops, some say don’t bother until run in more.
Any comments? - Other than telling me that I know bugger all on this subject, which I already know!

[bryno]

Looks just fine mate, nothing to be concerned about, i dont think its that oily bearing in mind you are running in

You do need to do a proper 'under load' plug chop, but you cant really do that until it's run in and you are happy to open it up, if you are at all concerned, stick a 112 in for the plug chop and if its too rich, go back to the 110 and try it again

Dont need to do a plug chop again once you are happy with the set up, its not something you need to do regular, not unless you change something else like carb or exhaust..

[sbwnik]

I'd be happy with that too, you'll get more oil residue at low revs anyway, and the spark gap looks a healthy chocolate brown (on this screen anyway!)

[sime66]

That's encouraging, thanks chaps. More of the same then for now...

[pxguru]

For me that plug is one number too high. What number is it?

Mixture looks fine for running in but for no problems at all I would put in the 112 jet as Bryno said ;D

[sime66]

That’s a B7. I’ve gone from a 108 to a 110, but will give a 112 a go. I’m going up to an SI24 carb anyway (with a 116), once I’ve got this change settled right.

[sbwnik]

If it's a Polini 177, go to a 24/24 with stock 200 jetting in it.

[sime66]

Nik, I’m going to upgrade the carb after sorting out this business with the piston, I've got that used pukka Dellorto 24/24 to try first. Sorry to say it’s a DR kit, which I note you don’t rate much.
The running in has had a setback today though. I’m on 300 miles now, still sticking to half-throttle and 40mph max, but today it spluttered and cut out. It started again, ran spluttered and cut out. I pushed it home; it started again, but wouldn’t idle without a little throttle. Now it will start, but as soon as a gear is engaged or I try to pull away, it cuts out. I couldn’t be bothered to faff about after pushing it home, but I’ll look at it tomorrow. It didn’t feel like another seize, more like a splutter than a drag like before. Anyway I had a look at the plug, which is attached - surely too oily now? I’m sort of back to investigating the problem before the seize, but I’ll have a better idea tomorrow.

[joey]

If you're running in and only doing 40 ish I'd say that your running a bit weak........ I'd go up a few sizes on the main.

[kru251]

Sounds to me like you're running it in a bit too carefully for it's own good. You need a few bursts now up and down the rev range to get the rings bedded-in etc. Lots of low speed running in just produces rings that are glazed; as is the bore. I'd suggest a few more up and down the rev range and start making it work a bit. Not long sustained revs but variable with a few five to ten second nearly flat out runs then backing off gently. Buzz the engine a bit through third too. Constant speed is your enemy at running-in time. Otherwise you will get to four hundred miles and only be run in the same as if you'd done two hundred miles. We ALL have differing ideas of what to do but this approach has done me OK so far!!!!!

[sime66]

I've got to get it running again first.
The first 300 miles have felt really good, and I was getting confident with it, and pushing past those limits a bit, thinking it felt pretty normal. I wondered if I had pushed too far too soon. It's mainly lanes and hills here, so lots of lovely changing up and down for bends and hills. I'd done two separate runs of 20 miles today, and was out for a third run to take me past 300. I was expecting another smooth 20 or so. No other sympoms, except the spluttering and dying. I'll see what's going on tomorrow, but I put it away not running tonight.

[kru251]

First bet, just change the plug. Might sort it straight away. If not, carb with dirt/rust particles.
Seems there are quite a few of us all out just "putting on the miles"
Good Luck.

[sime66]

Thanks kru251, I saw that you were also doing some running in.
I’ve put a cleaned, newish plug in every time I’ve checked it – and cleaning the one I remove for re-use.
I also tweaked up my idle screw just a touch this morning, which seems to have sorted the cutting out, and with a bit of coaxing she was off again.
With your previous comments in mind, here’s where I’m at after a 10 mile spin this morning:
300+ miles, Still half throttle – 3rd gear to 45mph, then 4th gear to 55mph, without revving too high or too long, and just for a moment then throttling back to just above 40mph. That’s my old Veglia speedo - nothing flash on mine. There is a bit of a lumpy patch around third throttle, but plenty more past half throttle, and all feels really good, except for that unexpected blip yesterday. So I’m going to carry on putting in the miles, and just push it up a bit. Do you think I should stay longer in each gear and increase my max speed and throttle a bit more yet? I note that several people have said to go up another jet too, but I’m thinking that’s more like the area of the carb I’m approaching now.
All being well it’s local miles today, across the Moors tomorrow, and Lands End on Sunday/Monday for Pete’s SSAFA ride.

[sbwnik]

300 miles on a new top end.

Thrash it now, it'll be bedded in.

[kru251]

Well yes, I'd be giving it a few more beans as I work on about 350 to 400 miles to run it all in totally (and my Li 198cc L*******a is a 100%, fully rebuilt engine in all respects).
Like I said you'll just be repeating the situation you were in at 150 - 200 miles continuously so get that throttle open. I still wouldn't have it labouring of course but 'buzzin' the engine/revs now is good!

[sime66]

She’s had a sound thrashing with extra beans! Good blast round the lanes and over the moors. Not quite full throttle, but 70mph on my old speedo without over doing it. All good, no worries at all. 400 miles now – sorted.
Now, about this carb………………………………. ;D

[kru251]

Apr 5, 2013 13:23:22 GMT sime66 said:

She’s had a sound thrashing with extra beans!

I thought I'd logged into "sadomasochism-for-grocers.com" there for a moment!!!!
Glad it's all singin' well!!!

[sime66]

No vegetables have been used for testing….

Everything is running lovely, and it feels really good and lively. I wouldn’t yet say better than before because it has always run well, but certainly OK after the changes.
This is my plug after a good thrash yesterday, up to 390 miles:



This is my plug this morning after a 10 mile, high-revvy warm up and a plug chop. Those marks on the isolator were already there because this is the cleaned plug from when I seized it a few weeks ago. Can anything worthwhile be determined from colour and oiliness? Or should I be using brand new plugs for this?



This looks a lot like the sort of plug I was getting before the seize and piston change, so I think it’s pretty OK, isn’t it? My main dilemma now is whether I need to do anything with the main jet on this carb for the time being, bearing in mind that I am going to change to a 24/24 anyway – probably after Tenby. I currently have a 110 on a 20/20, and most people here reckon a 112 would be better, which I would have to order.
You’ve given me a lot of advice already, so thanks for that, and for any comments on this anyone may have.

[joey]

It looks ok to be honest, maybe a gnats knacker weak but the 112 should sort that out.
When you say plug chop how did you do it? Not being funny but a lot of people just take it for a blat then bimble home and check the plug which doesn't give a proper indication of what's going on.

[sime66]

I took it for a ten mile spin, going up and down through all the gears plenty, givving it loads in 3rd and 4th, up to about 70mph. Then there is a long quiet lane where I went up to about 60mph, slowed to about 40mph, pulled the clutch in, turned the ignition off, stopped as quickly as I could, took the panel off, pulled the plug out, and photograhed it as soon as I got home about 10 mins later. I wasn't really happy trying to do it all at once going any quicker than that, but I could if I need to.

[kru251]

I'm the kind of sad git who does a plug chop, then waits too short a time and takes the plug out (with burnt fingers) to check it there and then!!!
BUT, I'd say that was too weak too. Remember that now is the false dawn when you have just got it all run in and then start using near max revs for longer times. A short period of weak running can be got away with; but sustained.....................well you know the answer.
Slightly richer would be better IMHO.

[joey]

Easiest way to do a full bore plug chop is to wring it's neck in 3rd for about 30 seconds, clutch in, ignition off coast and check.
Bit of a faff but the only way you're going to get a proper reading.
By slowing down to 40ish you're not fully on the main jet and it honestly doesn't take long for the plug to give a reading on the throttle setting you were using when you switched the ignition off.

The way I do it (not saying it's the best, or the only way,) is to mark my handlebar with 1/4, 1/2, 3/4 etc and check plug at different settings........... it's all well and good knowing that you're running clean at full throttle but not if you spend most of your time bimbling with others at half throttle.

[sime66]

I did take the plug out immediately - the burning was light relief to my poor frozen hands! I pocketed (in its box) that plug, rode home on a fresh one. However I take two valuable points:
. Do not go to Tenby 'lean' - get the 112 sorted immediately.
. Tomorrow (when roads are quieter) do a series of plug chops as described by Joey:
On a warm engine, thrashing it in 3rd, and also others at quarter, half and three quarter throttle (already marked for running in).
Obviously, repeat plug chops with new jet too.
Thanks chaps!

[pxguru]

I think it looks very weak
I would put in a 118 main jet (easily available) and a B6HS plug and do another plug chop.
You're lucky that didnt seize up already!

[sbwnik]

That bottom plug is definitely lean. A B6 will be too low on that, if it's running lean now, then it'll be too hot for a 6

[sime66]

I'd already ordered a 112. I don't mind ordering a 118, but I do have a 116 here (it came with the 24/24 I've got). Also, it was very cold this morning.
Would it be sensible to try plug chops with the 116 and the 112, early next week when it isn't actually freezing, and still with the B7? I'm trying to decide on the best action given the comments received.
Also, forgive my ignorance, but how have I got a situation where I'm thinking about jetting my 20/20 higher than is standard for the 24/24? Does it suggest something is still wrong? Or just that I need to be using the other carb?

[sbwnik]

I'd stop p*shing about with the 20/20 and get the 24/24 on. Otherwise you'll have to start all over again.

[pxguru]

The 116 will be enough in the 20/20. Way better that what you are running now anyway. As Nik says get the 24/24 on as soon as!

The B7 in that picture is not getting hot enough but is running weak Once it is jetted properly it will be more obvious.

[sime66]

I'll put the 116 in the 20/20 today. I'll do the 24/24 asap.
I haven't changed a carb before. I'm hoping the 2nd hand pukka Dell'orto is good. I have had a look at it, but I don't know whether to strip it completely, or get in on and try it. I'll start another thread, and if I'm asking too many questions, you can ignore it and I'll get the message!

[sime66]

Still on 400 miles. Put in 116 main and did rapid ten miles, then, for the purposes of comparing like-for-like with yesterday, a pathetic plug chop the way I did before. It at least indicates an improvement? I'm out of time this morning now, will do proper plug chops tomorrow, but I hope it's enough until the 24/24 gets sorted - or is it still too lean?