Very rich. Is the rear one the same? Possible causes are faulty coolant sensor, air temp sensor, or Lambda sensor or MAP sensor, although I'm not sure if the 848 has them.
Yeah below 6000 rpm its bogging/juddering very badly at times but clears if i accelerate hard then comes back. Had new coils packs, plugs, TPS re set, fuel filter, throttle bodies balanced and fuel/fan relays. Ran well after all this with new plugs but after about 100 miles started showing slight symptoms again and got worse over the next few days until now terrible again. This plug has done no more than 200 miles
Not checked rear plug yet but will do, below 6000 rpm bikes bogging/juddering very badly at times but clears if i accelerate hard then comes back. Had new coil packs, plugs, TPS re set, fuel filter, throttle bodies balanced and fuel/fan relays. Ran well after all this with new plugs but after about 100 miles started showing slight symptoms again and got worse over the next few days until now terrible again. This plug has done no more than 200 miles. Bikes has a full termi system and DP ecu from new
The ECU has a map which determines how much fuel is injected depending on engine speed and throttle opening from the TPS. This is modified by; the coolant sensor which adds more fuel when the engine is cold, reducing as the engine warms up, Air pressure sensor which will very the fuel depending on the altitude and ambient air pressure, and the air temperature sensor which will reduce the fuel at higher air temperatures and reduce it a lower temperatures. Any of these can change the mixture but the most likely culprit is the coolant sensor which has the biggest effect. The Lambda sensors work at lower revs usually below 4,000rpm in what is called the 'closed loop' section of the fuse map.The Lambdas will try to keep the air fuel ratio in the cleanest burning state with an air/fuel ratio between 14.3:1 and 15.1:1. Faulty Lambdas usually make for a poor running engine at lower speeds but it will run better at higher speeds once it gets out of the closed loop section of the map. So any of these could be causing your issues, most likely the coolant sensor or one of the Lambda sensors. If it is only the from cylinder that is affected then it is probably the lambda for the horizontal cylinder since any of the other sensors will affect both cylinders. But really the best thing is to get a diagnostic software such as Melcodiag on it and see if anything shows up. Error codes or sensor values that are abnormal.
Thanks i'll pull the top plug and take a look, I have it booked in at BSD a local dyno place that specialise in bikes but they cant fit me in for 3 weeks. Hopefully once on there dyno and hooked up to there software they will get to the bottom of it. I expect if I put fresh plugs in it will run fine for a while again then they will foul up. I fitted new fuel pump and fan relays today but without fitting new plugs I cant tell if they made a difference or not.
Oddly about 10 months ago I got caught in very heavy rain and got a lamba error code come up, it went once bike was dry
Has the CO level been set correctly. With the full system ECU the CO can be adjusted manually using the likes of JPDiag, IAWDiag, Scan5MX. I used a Gunson Gas Analyser to read the CO level when doing this.
Honestly don't know only had it a year but has full main dealer history, the problem just started when on a ride several weeks ago, has be fine for the last year prior to that and ive covered 2000 miles on it..
My 916sp motor ran beautifully but was only returning 15 to 20mpg it didn't misfire even though the plugs were very black I changed every sensor and the thermostat except for the air temp sensor On the 916 the colder the air temp the more fuel gets chucked in When I eventually checked it I found it had a very high resistance so it was telling the ECU I was riding round the North Pole. (The higher resistance the colder the air) I bought a brand new one and now its doing 40mpg
Pulled the top plug and looks pretty much the same as the front one (top on the right in photo) so what ever the problem is its effecting both cylinders the plugs have done about 150=200 miles. Fitted a new fuel relay yesterday so will see how it runs now i've fitted new plugs again. Seems to run good for about 100 miles then the miss fire/juddering below 6k symptoms start again and gets gradually worse which I guess is the plugs getting sooted up...
