Last year i had a couple of electrical problems probably connected with having a lithium battery fitted to my 2007 1098. i removed the airbox and inspected everything including a leak at the front fuel injector. i did notice that there was a small build up of black stains on the valves near the stems in the front cylinder. Was advised to use some valve cleaner and never though much about the rear cylinder until i disconnected the exhaust system to give it a clean and polish. everything inside the rear cylinder was black with soot. i also noticed that a plastic plate had come loose inside the airbox, so i cleaned the edges and glued it back into position. Could this loose plate be the problem for the rear cylinder turning black with soot since the bike had the shims done in 2020 ? . the plastic plate has a hole cut in it to allow fumes from the gearbox to escape. the plugs were renewed and the bike only did 50 miles last year due to knowing about the fault. when i used the bike it ran ok until the revs dropped and it cut out.
Is it not just more likely the rear cylinder is running a little rich ? Check the plug would be the first thing I'd do. As stock the maps are not cylinder specific. Most good tuning shops will map a per-cylinder fueling solution.
Well worth checking that the fueling is correct for both cylinders, and if not finding out why - faulty injector sensor etc. That amount of soot suggest excessively rich running. 1098s are prone to piston cracking if the fueling isn't right. Ask me how I know...
I don't know tbh. But I had that problem on my 1098 SF. Yours appears to be substantailly over-fueling on one cylinder and it warrants investigation.
just read some of my older posts on the subject and the mechanic said the TEXA came up saying the TPS needed resetting. i reminded him that if the tps is reset it would then need re-dynoed . he said that the adaptives had been reset electronically. i will check the plug just incase its faulty
Are we sure this is not just normal? Both my cylinders looks like that and I haven't experienced any running issues. Other than my r/r burning up at the same time I got transmission failure that is. Before I got my bike it sat for many years and only started occasionally so could be old soot.
the front cylinder head is very clean inside compared to the rear. it must be causing the bike to cut out when the revs drop.
Personally I think I would go for a 40-50 mile ride keeping it in lower gears to keep the revs and engine temp up then cut the engine as soon as you stop. See if the plug is a better colour.Could just be over fueling at low revs, they certainly don't run smoothly low down without a good remap on the ecu. Make a decision depending on what you find.
removed fuel tank today and the sparkplug seemed ok. the electrical connector on the injector is very clean as well as the fuel injector. i also removed the rocker cover to check the gaps in case it needs shimming . i have taken note of all gaps but i am not sure of the proper procedure. i have it in the TDC position and measured all gaps. is it at 4 locations where i measure for each cylinderhead ? .
I can send you the workshop manual. Pm me your email. I think desmowerx on YouTube have some good videos on how to measure clearance.
