Rough Idle

[kappy5003]

Although only running on 3 cylinders and pretty much in skeleton mode, had short run down the driveway (driveway is 500 metres)

Actually started without choke and only a tad throttle


Felt New fork seal and fluid seemed good, will have to wait for the bitumen to bed the new front pads and rotors in.

Been well over a year since I've been on back and actually ridden her (sounds dirty)

So all I need now is plug lead indicator control and get her dressed again.
 

[kappy5003]

Just an update,

I meet up with Yorkie yesterday and obtained a spare plug lead from him.

So after several tests I have come to the conclusion that neither the coils ,leads or plugs are faulty.

So it looks like I may have to pull the carbies apart again.

I can get her to idle once warm, but tell still right, still getting pops in intake and minor back fires at the exhaust.

I'm unable to fathom why when I pull either plug lead from right bank there appears no difference in the running however if i pull a plug from left bank it stalls.

Seems as though running on 2 cylinders and pull one plug from left bank and then really only running on 1, so stall.

Plugs on right side seem quite wet, so is that a mixture issue?

As I see it the only two aspects that are adjustable are the screw and the float?????

Any suggestions please.

May raw fuel is going into exhaust as it gets warm the exhaust starts smoking.

Cheers
Kappy

[alans1100]

I had something very similar happen when I did my timing belt.....something I did fixed it but what? I'm guessing that because of the loose clamp to much air was getting in one cylinder and creating what sounded like a misfire.

Because of the age of the bike I put new carb insulators (they get hard after 14 years) in: which made the carbs seat in easier.

http://ozstoc.com/index.php?topic=2977.msg38722#msg38722

[kappy5003]

Just an update guys,

My carby insulators arrived yesterday and they have been fitted, wow feel a whole different to the ones I removed.

Anyway as I have the carby's removed again, I'm double checking everything.like needle and seats etc;

Now I know number 3 was not firing and I have since checked leads and plugs and there is a good fat spark on the plug at that cylinder so must be something else

Is anyone able to advise me how I can check the float level and whether if the levl is wrong would that prevent fuel getting into that cahmber.

As I have to float cover off and as I move the carbs around so the float moves as well.

No point re installing carbs till I cover all options.

Cheers

Kappy

[Yorkie]

You can download the workshop manual from 1100 section if you don't already have it.

[kappy5003]

Well I'm just about done. I mean 

I've re fitted the new isolaters.

I re vsited the  carby and re checked float levels, pilots tets,

Seems I had Pilot screw out 2.5 turns and seeing Aussie bikes are the same as Canadian they only come 1 7/8.
So all reset, re fit carbys.

Turn on, ignition and away we go, away we go a lot better than last time, re sync carbys but still a little back fire from exhasut, mosting on back off.

However as temp increased, all of a sudden stalled  and wouldn't idle so fiddle with idle ajustment and manage to stablize idle.

Now while running sorta OK just not quite right, just don't what else to do.

Does anyone know a carby specialist in WA that's not gonna sting me.

I wouldn't think that pilots, idle jets etc would need replacing at 97K.

Help

[PC]

This is an experience I had with a XR600   start up cold would run find 10 to 15minutes it would start back firing ,popping lose power
it was just like it was starving for fuel it would behave  like when you run out and had to turn to reserve .  I would pull the carbie off clean it refit it, tune and it would run find for 10 to 15 sometimes you mite get 1/2 hr to 1hr I pulled the carbie out more than a dozen times , bought another carbie, played with float levels, finally  got the shits with it and  took it to bike mechanic . He said it fuel problem. pulled carbie out cleaned it . after he had done it twice he got the shits and threw his hands in the air as well . Just for shits and giggles we pulled the CDI unit out of a Chinese quad he had in the shop stuck it in the XR and BAM the thing was lethal. rode it for 18 months never missed a beat  So all I am saying is that it may not be carbie problem    when the XR was running properly you could tune it- when it started to play up you could turn the mixture screw to where ever you liked and  nothing would change 

 Hope this helps
  Peter
       

 

[saaz]

One of Lionel's st1100s had a problem with one spark plug cap not contacting the lead consistently. Spark was intermittent so hard to track. Someone must have been pulling on the lead to take it off. You could try doing a spark test with a plug with a big gap. In this case slightly trimming the lead solved the problem.

[Yorkie]

I have already given him another lead, prior to that he was getting spark at the plug, wondering if the problem is in the ignition control module when it starts to get warm or connection through side stand switch or something similar.

[kappy5003]

Haven't had much chance to check everything today.

However something I mentioned before and I don't know whether its normal or not.

Started her this arvo, and idle OK, but still not that smooth ST sound and feel we all know.

Now while running I remove lead 1 and or 3 and there is no noticeable change in running.

However when I remove No 2 lead, 1,3 and 4 still attached and noticed change. when I remove No 4 with 1,2,and 3 still attached notice changed and almost stall.

Surely if a plug is removed there should be some change, yes???

Cheers
Stumped

[winston66]

A dumb question,
Have you tried swapping No1 and No3?
Cheers winston66

[winston66]

Havent read all of the comments and or the posts.
Have you done a compression check on all of the cylinders , If you have done the tappet (valve)clearances how do the pressures on all the cylinders compare now?
In my previous post I was alluding to swapping over the plug leads for cylinders one and Three.
Cheers Winston66

[kappy5003]

Haven't done a compression test, don't have the gear to test.

I think swapping  No 1 & No 3 plugs leads wont work as I feel the prob is on right side, i will try later when cooler swapping over no 1 and no 2 .

Can the voltage at the lead be tested with a multi meter?

Any comments on Now while running I remove lead 1 and or 3 and there is no noticeable change in running.

However when I remove No 2 lead, 1,3 and 4 still attached and noticed change. when I remove No 4 with 1,2,and 3 still attached notice changed and almost stall..

Cheers
Kappy

[Brock]

Can the voltage at the lead be tested with a multi meter?

No!!!  You will toast the meter, we are talking mega volts here..

Pulling No3 & 1 with no change tells me something maybe wrong with the leads or coils. I think 1 & 3 are off the same coil..

Could be wrong but. Each coil feeds two plugs at once, going bang depends on whether its the firing or exhaust stroke.

[winston66]

If disconnecting any lead in particular produces a change in how the motor runs would tell me that the  cylinder from  which that particular lead that was just disconnected was operating properly, Ie that it had both fuel and spark.
If disconnecting another lead did not produce any change, then either the spark or fueling to that cylinder is faulty or missing. You have said that the  spark plugs of cylinders one and three were wet, so I assume that they are getting fuel but then they do not fire so I can assume that there is no spark. therefore, is there any activation of the respective  ignition coils. I am not conversant with the 1100 ignition system , I have the 1300 model.
If there are separate ignition coils for each cylinder is it possible that the primary feed to each coil has either been interrupted or inadvertently transposed to the other coil, that is why I suggested that you swap the spark plug leads from No. one and No. three.
A multi meter is not suitable to test the high voltage output of an ignition coil.
A bad adjustment , (too tight) ,to the tappets will probably cause a hard starting and very rough idle problem as the respective cylinders will not be able to obtain the correct compression for efficient operation.
Cheers , Winston66

[kappy5003]

Thanks about the Multi meter  I thought as much just asking.

Yes there are two coil one feeds 1 & 3 and the other 2 & 4.

There appears to be spark, but doesnt seem that strong, if its weak will that affect the running or will any spark cause ignition.

I have double checked my settings on the tappets, actually about 4 times, and the shims that were changed were a thou.

If the carby is out slightly will that affect one side not firing properly? 

[Brock]

A weak spark under compression may not spark at all, or provide week ignition so the fuel air mix doesnt burn properly.

[Bikebear]

I'd be looking at getting hold of another coil to replace the one that feeds 1 & 3. Should be able to score one from a wrecker pretty cheap or maybe even ebay.

[kappy5003]

Well I just went out and swapped no 3 and No 1 leads no change.

So idle for about 10 mins to see if I could get a sense of anything, so felt pipe near engine, left side hot, right side cold.

Hence when I remove say no 4 plug she stalls, even a good 4 cylinder cant run on 1 cylinder.

So either right coil,
OR can carbys adjustment be so fart out to having this affect even though each carby re assembled with same basic setting, really only fine tuning a as I see it.

Is it possible Iv'e missed a vacuum line somewhere?

[kappy5003]

Well I just went out and swapped no 3 and No 1 leads no change.

So idle for about 10 mins to see if I could get a sense of anything, so felt pipe near engine, left side hot, right side cold.

Hence when I remove say no 4 plug she stalls, even a good 4 cylinder cant run on 1 cylinder.

So either right coil,
OR can carbys adjustment be so fart out to having this affect even though each carby re assembled with same basic setting, really only fine tuning a as I see it.

Is there a simple way to test coil?

Is it possible Iv'e missed a vacuum line somewhere?

[Brock]

You could try swapping the coils, and see if the problem swaps..

[kappy5003]

You could try swapping the coils, and see if the problem swaps..

Brock as the coils are  not readily accessible, do you know an easy way to do that?

Is it possible to swap the feed wires to opposite coil without having to remove?

May be a job for Wednesday, Doctors appointment MON & TUES.

[Brock]

Havent had to look at the coils, so dont know how hard to do, it may be possible to swap the leads over.

[Yorkie]

I have a spare pair of coils, I think you would have to remove the radiator to change them.
I don't think it would be possible to swap leads, (both electrical and ignition), without removing the radiator, the coils would have to be turned around.
As previous, I don't think it is a fuel problem.

[kappy5003]

Got them out, just a bit fiddly, there has to be a way testing, with a multi meter.