Rich Idle & decel

[SizemattersIII]

Bike has all of a sudden started idling rich but idles ok & decel is really rich. So rich it illimnated all the decel pop. thats good but MPG has gone to hell. Bike cruises down the road smoothly & excellerates good. About a week ago I stopped & filled up with gas on the way to work. Rode approx. 3 miles after filling up. About an hr later after coming into work a fellow biker came in & said that the my bike was leaking gas. Went out & checked it & found that it was coming out one of the overflow tubes. Leaked probably 1/4 gal. Didnt think to much about it at the time, because it stopped. Thought it was just fuel expansion. Am begining to think that there could be something else going awry. Have flashed ECU with original tune, adjusted ISCV to spec. and reset adaptives. Didnt help. Any suggestions.

 

[SizemattersIII]

If you fill the bike and then leave it in the sun you can watch a big chunk of your fuel dripping happily onto the ground. This will make a big difference to your MPG. If you were to check it after about 100 miles then you could easily loose an effective 10% fuel economy. Fill up at the beginning of the ride, not the end.

I understand the fuel expansion theory. I get that. i didnt make that mistake again. The bike is running really rich. You can smell the rich mixture coming from the exhaust. Kinda burns your eyes. On my last fillup I only got approx. 165 miles out of the tank. Not good. Hooked up to TuneECU not getting any codes. Would this be a throttle body thing? A bad TPS thing causing rich mixture? They normally cause hi idle. Possible ECU? Bad Injector?. Suggestions where to start.

 

[Triple Trouble]

As the bike is running smoothly I would rule out anything which is specific to one cylinder such as a bad coil or injector and look for something common. I'd look first at the TPS. I've wondered about those laser temperature gauges where you point and shoot to get the temperature of an object. I checked my Rock with one and found approximately a 25 deg F difference between cylinders. No idea if this is good or not but would think you could quickly identify a poor running cylinder ?

 

[SizemattersIII]

Ive reset the TPS & ISCV with tuneecu but, Im not ruling it out. Ive had to reset the tps several times for high idle. It still has the orginal TPS. I did do the shim mode to it. Am looking at it seriously.Proabaly a good time to upgade it. I will still check all the obvious, coil wires, plugs, etc. Like I said before, I flashed the ECU with a lean tune.

 

[Blastedbones]

standard air filter? clean? no kinks in the air lines? might be time to put the new style TPS on tho...following that, mebbe a dyno run to check just what degree of richness you are actually running with.

 

[valmacmiami]

See my fuel consumption thread I had same problems and tried everything narrowed it down to leaking headers and new tps bike now runs great

for an extra 20hp you could paint engine with hi heat black paint

 

[SizemattersIII]

See my fuel consumption thread I had same problems and tried everything narrowed it down to leaking headers and new tps bike now runs great

for an extra 20hp you could paint engine with hi heat black paint

Or I could recoat silver for an extra 40 hp


Ill retorque the headers (just installed new header gaskets) & exhaust clamps. Upgrade the TPS (have been suspicious of the TPS for a while now). Im running K&N filter & just cleaned it 10,000 mi ago. All hoses are good.

thanks for replying fellow captains.

 

[SizemattersIII]

Update: It definitely was the TPS. Got the new one installed & setup, bike runs like brand new. FYI, used a .016" shim instead of .010"

Thanks for the insight Valmac.