Running rich but only on one cylinder.

mspenz · Mar 21, 2019

I'm even more confused now..

A cylinder leak down test today showed both are in very good condition with only minimal leak and if anything the right cylinder/head had slightly less leak at under 8.
Given the results of the compression test and now also this it seem unlikely that it's a mechanical problem ( piston/rings/valves/guides etc ) as all the results are pretty damn good so it's probably not worth taking the head off as there's unlikely to be anything obvious causing this ?

I've ordered a used ECU from Motorworks just in case the injector is getting a corrupt signal and staying open too long but I'm really clutching at straws now :nenau

If the ECU isn't the problem then Motorworks will let me return it and they'll refund so I can't ask for more than that :thumb2

I put 2 new EGK plugs in this morning before riding 10 miles to get the leak test done and they were noticeably different shades even after that short run.

The 1150 section has suddenly got a bit busy ..

Mike.

gog · Mar 22, 2019

Mike have you sprayed easy start (or carb cleaner etc) around the throttle bodies whilst running, to rule out air leaks?

As mentioned before this would usually result in a lean mixture though. Is your exhaust stock, with the lambda sensor in the collector box? Im sure I have seen aftermarket Y pieces with the lambda bung in one side. Clutching at straws but could explain why one side is rich if the O2 sensor is getting skewed readings from an air leak.

mspenz · Mar 22, 2019

Hey Gordon. Yeah, I've sprayed WD40 all around and there's no difference at all, also the probe is right in the middle where the down pipes join so everything should be even and balanced.
I'd also assume that the ECU will send out equal signals to each side based on the information received ,and that it doesn't compensate and alter the mix to each side independently...but I could well be wrong ?

I have a Black Widow end can fitted , there's also an AF-XIED in line and the bike still runs well but it's going to carbon up and cause other problems if I don't figure it out !

Mike.

gog · Mar 22, 2019

mspenz said:
I'd also assume that the ECU will send out equal signals to each side based on the information received ,and that it doesn't compensate and alter the mix to each side independently...but I could well be wrong ?

I was more suggesting that the probe sensed a leaner mix if it was on the 'leaky' side, and richened things up overall, causing soot on the non leaky side. Moot point as youve ruled it out anyway.

Best of luck figuring it out. See you at Dent :beerjug:

Ian J Hartley · Mar 22, 2019

OK this is a long shot, and I’ll probably get shot down in flames by the more knowledgeable.

But, the air intake tubes are different lengths inside the air box. My understanding is that that is to ensure the charge of air to each cylinder has equal distance to travel.

I think, but am not sure whether these tubes can be fitted the wrong way round ie the left one gets fitted to the right side and vice versa (Some of the more learned will know if this is physically possible). This would cause an air intake imbalance, fuel to air ratio, which may point to your symptoms.

But it’s a long shot. Your tubes would need to have been removed at some stage in the bikes history and refitted incorrectly, if that is possible. Or as they are a two piece construction, glued together, maybe they have fractured inside the air box.

The tubes themselves have both left and right stamped on them, but have different part numbers to differentiate between position 13711341405 left and 406 right.

I seem to recall, though again I could be talking bollocks, that there have been instances where people have swopped these tubes from other models in order to improve mid range torque

Ian J Hartley · Mar 22, 2019

mspenz said:
I've ordered a used ECU from Motorworks just in case the injector is getting a corrupt signal and staying open too long but I'm really clutching at straws now
Mike.

The injectors are not individually powered. They are both powered together from the same single output from the motronic. That’s what a simple motronic system does (aka wasted spark system). One pulse for the ignition (spark) one pulse for the fuel (injector). So each cyclinder gets 2 shots of fuel and two sparks per cycle, but the bang only occurs when the spark occurs on the cylinder in compression. The motronic doesn’t need to work out which side is which because it does everything to both sides at the same time.

If it were physically possible you could swop the wiring from the left side injector and the HT to the plugs from left to right side, and vice versa, and the bike would still run.

mspenz · Mar 22, 2019

More info to confuse me..
The intake tubes have never been altered and this only started happening mid way through a trip last year. I'd changes the plugs and done the usual stuff before the trip and the plugs were pretty much perfect then.
The inside of the left pannier started sooting from the exhaust and I heard pinking from that cylinder a couple of times under load.

The TB balance is still pretty much perfect and untouched in 4500 miles.

Bang goes my ECU theory then !

Ian J Hartley · Mar 22, 2019

Some more clutching at straws......

The crankcase breather pipe feeds into the top of the air box on the right hand side. Which is the same side that you are showing a richer mixture.

When was the last time you drained the air box?

The bung is on the left hand side, bottom, rear of the air box.

JJH · Mar 22, 2019

mspenz said:
More info to confuse me..
The intake tubes have never been altered and this only started happening mid way through a trip last year. I'd changes the plugs and done the usual stuff before the trip and the plugs were pretty much perfect then.
The inside of the left pannier started sooting from the exhaust and I heard pinking from that cylinder a couple of times under load.

The TB balance is still pretty much perfect and untouched in 4500 miles.

Bang goes my ECU theory then !

It shouldn’t be pinking if it’s running rich. JJH

mspenz · Mar 22, 2019

Ian J Hartley said:
Some more clutching at straws......

The crankcase breather pipe feeds into the top of the air box on the right hand side. Which is the same side that you are showing a richer mixture.

When was the last time you drained the air box?

The bung is on the left hand side, bottom, rear of the air box.

TWG mentioned this on the first page but I forgot to check :blast

.
I'm not quite getting it though..if there's any oil lying in the box then it will drop into the lower part with the drain valve and anything left will find it's own level and so would effect both cylinders ?

I'll check tomorrow anyway :thumb2

mspenz · Mar 22, 2019

JJH said:
It shouldn’t be pinking if it’s running rich. JJH

I don't know if it was pinking and I only heard it a couple of times..once in Turkey overtaking up a hill and the next time was 1500 miles later on the way home. I wear ear plugs all the time but it was definitely that type of noise and from the right cylinder area...otherwise it's all quiet..well, as quiet as an oilhead can be

mspenz · Mar 22, 2019

gog said:
I was more suggesting that the probe sensed a leaner mix if it was on the 'leaky' side, and richened things up overall, causing soot on the non leaky side. Moot point as youve ruled it out anyway.

Best of luck figuring it out. See you at Dent

Take more cake :thumb2

Roger 04 RT · Mar 23, 2019

mspenz said:
These are out of a 02' single spark after 3k miles and the bike has done 36k miles overall.
When I have panniers fitted the box next to the silencer soots up quite quickly and that's how I first noticed it.
Bike runs well and gave me an average of 50mpg on a trip with a pillion last year so there can't be much wrong !

View attachment 404131

I've changed the plugs, air filter, fitted a spare TPS I had, changed the injectors for a newly cleaned and balanced pair but the right side plug is still showing rich.
So...done a compression test and the results seem inconclusive ( for my limited knowledge anyway ).

LH cylinder shows 150psi with throttle closed and 215psi fully open.
RH cylinder shows 140psi with throttle closed and 205psi fully open.

Add a squirt of oil to the right side and it shows identical readings to the left.

Is that slight drop in pressure on the right pot enough to cause the dark plug, I thought that if they were within 10% of each other that would be considered as reasonably well balanced ?

New rings

Or is there anything I've missed ?

Mike.

Mike, Given all the tests you’ve made, I’m not sure you have a problem. Carry a couple spare plugs and check things in 10K miles.

Btw, what exhaust system do you have, is it stock up to the end can?

What setting are you running on the AF-XIED?

mspenz · Mar 23, 2019

mspenz said:
TWG mentioned this on the first page but I forgot to check .
I'm not quite getting it though..if there's any oil lying in the box then it will drop into the lower part with the drain valve and anything left will find it's own level and so would effect both cylinders ?

I'll check tomorrow anyway

Less than one teaspoonful came out and that's since I got the bike so I don't know when it was last drained..no problems there though.

mspenz · Mar 23, 2019

Roger 04 RT said:
Mike, Given all the tests you’ve made, I’m not sure you have a problem. Carry a couple spare plugs and check things in 10K miles.

Btw, what exhaust system do you have, is it stock up to the end can?

What setting are you running on the AF-XIED?

Hi Roger,

As far as I am aware it's a Remus Y-piece and I've fitted a Black Widow end can. I fitted the AF-XIED as I got great results from one on my other bike ( twin spark 1150 ) and this bike was surging at lower speeds in traffic and around town, nothing would shift the surge until I swapped the AF from the other bike and it instantly disappeared..smooth and steady right through the entire range.
I tried it at 8 and it tended to cough a little so I'm running at 7 now and it seems to like that.

My only concern is carbon build up over time and just on that cylinder...I don't want to burn a valve if I can help it !

I maybe will just run it for a while more and keep an eye on things but it really bothers my OCD :comfort

Mike.

fizzer · Mar 25, 2019

if this is any help to you as a compare ,these are my plugs from my r1100rt totally std bike with 28 thousand miles the one on the right cyclinder is running ever so slightly richer than the left.

mspenz · Mar 25, 2019

There's a theme forming

mspenz · Mar 30, 2019

I'm still not happy, there's too much mixture difference between the cylinders so there has to be a cause ! The bloke who does my car repairs is also a bike freak and track days on a Blade is his thing..he didn't like the mis-match any more than I do.
He also has one of these in his workshop https://tecmate.com/products/vacuummate/

A nifty bit of kit that can even point towards a particular valve. He'll get it plugged in over the next couple of weeks and see what shows up but I'm thinking head off, replace stem seals, check all valve seats, check/replace rings if required, re-seal sweaty base gasket...ride bike to Turkey and back, clean/service etc and then sell !

I'm going to hang on to my other twin spark 1150 GSA but I'm debating whether to go for a Yam generation 2 S10 or the polar opposite R100 GS PD as a 2 up travel bike

JJH · Mar 30, 2019

I think we’re all clutching at straws here but by any chance could there be a air leak anywhere in the intake system including the good side? And while we’re at it could there be a leaky exhaust? Apologies if this has been eliminated already. JJH

mspenz · Mar 31, 2019

JJH said:
I think we’re all clutching at straws here but by any chance could there be a air leak anywhere in the intake system including the good side? And while we’re at it could there be a leaky exhaust? Apologies if this has been eliminated already. JJH

Thanks for the input JJH. I've gone round both intakes with WD40 more than once and the exhaust seals well..I'll see if that VacuuMate shows anything else up.

Running rich but only on one cylinder.

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