back fire through throttle bodies?

[kblahetka]

Hi,
I resynced my throttle bodies a couple of weeks ago. Since then I've noticed on occasion (more in the cold) I get a what sounds like the bike backing firing through the throttle bodies. It's just a pop sound from that area and the bike sort of skips a beat. I thought maybe I had some of the plumbing on wrong and since it was such a nightmare to *****with I put on the triple filters, re did the tune and I still get the same thing. Any ideas?

 

[CanberraR3]

Mine does it sometimes too, only in cold weather and bike not warmed up. If it's only in those circumstances and goes away, I wouldn't worry too much. Pretty normal.

 

[kblahetka]

sweet. Thanks

 

[Idaho Red Rocket 3]

Is it a "little" pop ? Potential fire start hazzard. Keep your insurance up to date.

 

[kblahetka]

yes, its just a little pop

 

[warp9.9]

check vacuum leaks and make sure throttle bodies are seated down on the runners going to the head a little air going the wrong way can create a missfire. also check and crimp low tension leads to the coils. make sure they are claen and use dialetectric grease the squeeze them with needle nose piliers to make sure they are snug on the coils. remember our bike have a wasted spark system the plugs fire on every stroke.

 

[nolton]

remember our bike have a wasted spark system the plugs fire on every stroke.

I didnt know that one.

 

[kblahetka]

thanks warp. I out some clamps on the vacuum lines where they link. Its going to rain for the next few days so I'll see how it goes.

 

[warp9.9]

Ya just think about it the vacuum line leaks the map sensor reads a different millabar techno stuff pluss TPS % then addd the wrong fuel because of the leak ok and then the timing is off also because of the Ltable versese the timing table. Just taking a educated guess here hoping a knowledgable man like Neville Lush Racing will come on and straighten things up plus let me know if I am even close. Its hard to draw the teachers out even when acting like a dumb Polock

 

[TR3ROADSTER]

Try changing your fuel to 95
These engines don't like higher octane fuels

98 to rich
95 just right
91 to lean

Just some testing over the year