Engine Trouble Engine dies at idle once warmed up.
- Thread starter jmden
- Start date
I've got an 'aftermarket' filter like this http://www.bikeberry.com/bbr-tuning-speed-carburetor-air-filter.html with a velocity stack http://www.bikeberry.com/bbr-tuning-billet-carburetor-velocity-stack.html between it and the carb. But the water idea should work. Thanks!
Well...That RTV sealant was so well adhered to the top of the case halves there below the carb I just decided to leave it there and go for a test ride first and see if anything was different. It'd just stopped raining and was 40F, so took a few tries to get the engine going--starting the engine with the SBP jackshaft shift kit is a little more difficult than without and moreso with a cold engine in cold weather...
The idle seemed quite high immediately. I screwed the idle screw out to a reasonable RPM and ran the bike around for awhile to warm it up. Then, I took carb cleaner and sprayed it where the RTV was in the same manner as I did before the RTV was applied. Little to no change in engine RPM. I sprayed all around head gasket, cylinder gasket, rest of case halves gasket with no more changes in RPM.
The engine ran fairly good at WOT. Does the fact that the idle picked up considerably mean that there was indeed a leak in the case half below the carb? I guess plugging a leak there would make the fuel mixture richer, but would that cause the idle speed to increase? That doesn't seem right.
The idle seemed quite high immediately. I screwed the idle screw out to a reasonable RPM and ran the bike around for awhile to warm it up. Then, I took carb cleaner and sprayed it where the RTV was in the same manner as I did before the RTV was applied. Little to no change in engine RPM. I sprayed all around head gasket, cylinder gasket, rest of case halves gasket with no more changes in RPM.
The engine ran fairly good at WOT. Does the fact that the idle picked up considerably mean that there was indeed a leak in the case half below the carb? I guess plugging a leak there would make the fuel mixture richer, but would that cause the idle speed to increase? That doesn't seem right.
Street Ryderz
Well-Known Member
When the engine is sucking in air where it shouldn't be it leans the a/f mix but when the leak is in the case seal it can also blow out and like mentioned above with the big jet making the difference up for the topend the idle and slide opening was also more just to get it to run.
So a leak on the case seal would be blowing OUT oil/fuel mix...right? Which I never saw evidence of--no leakage on case seal anywhere that I've seen, yet it seems like that putting on the RTV made a difference...huh? So if there was a leak in the case seal...I'm trying to wrap my head around what that does to the engine...does that make it need a bigger jet because it's losing oil/fuel mix? So, I should be able to jet down now, right?
Street Ryderz
Well-Known Member
In or out even both wreaking havoc to the set up.If it was just sucking in you would not see it,if it was doing both or just out you would see accumulation on anything that may be above it first as it would take awhile for residue to build up at the hole it's self because it's comming out under pressure not just spilling out and sitting there.And yes you should be able to rejet and dail it in now.
Could the case halves be sucking in there under the carb if the gasket there wasn't sealing? Which is it there specifically? Sucking in or pushing out? Sucking in would create a lean condition 'corrected' by the bigger jet, right?
So, since I did not see any oil/fuel mix coming out there, it seems like it was likely sucking in, right, creating the lean condition corrrected by the larger jet...? But if that was the situation, why would that seem to create a lean condition at idle, causing the engine to suddenly idle high when started up again after apply the RTV? Still trying to correctly understand what's going on here.
So, since I did not see any oil/fuel mix coming out there, it seems like it was likely sucking in, right, creating the lean condition corrrected by the larger jet...? But if that was the situation, why would that seem to create a lean condition at idle, causing the engine to suddenly idle high when started up again after apply the RTV? Still trying to correctly understand what's going on here.
gary55
Well-Known Member
If it's running good now, it's idling good now, and their are no visible leaks their is nothing going on. ride it and have some fun.
Street Ryderz
Well-Known Member
Your idle adjustment for slide position was in to far from the leak issue so yes it needed to be reset.
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