bikefireing when changing down gears

[probusa]

hi all just took my wife out on the bike and twice today when changing down thro the gears i get a sound like a backfire

it happens sometimes when i rev down the gears (just after i pull clutch in and give alittle rev).
it sounds like it comes somwhere under the tank on the left hand side.
yet if it was a backfire it should be on the right side coz i got full yoshi 4into1 system on it.
any help would be good.
regards
[/blur]PrObUsA

 

[Sloto200]

Did you change your exhaust gaskets? You might have a leak if your hearing "backfiring" from under the tank... It could be that you are backfiring and that would be a result of the pair valve igniting excess gas in your exhaust. Since you have an aftermarket exhaust you will have less back pressure and more unburnt gas to burn in the exhaust, giving you the backfiring. Almost everone on here will tell you that if you get a aftermarket exhast that they had the same issue. You need to either remove the pair valve or do the "marble mod" and block the hose that supplies fresh air to it right at the air box. I did the marble mod have have had no backfiring since.

 

[probusa]

as far as im aware all suzuki done was take original system off and replace it with yoshi.
i dont think they touched the gasket and to be truthfull i aint to sure what part that is either.all that sort of work i leave to garage.
it's 1 of those noises you cant really explain might sound silly but it sounds like a backfire and a pop at same time.

 

[dadofthree]

Pair valve mod man

 

[OZZY]

(dadofthree @ Jul. 18 2007,13:26) Pair valve mod man

+1

 

[Charlesbusa]

(OZZY @ Jul. 18 2007,10:29)

(dadofthree @ Jul. 18 2007,13:26) Pair valve mod man

+1  

 

 

+2

 

[heavybusa]

Marble mod too.

 

[Sloto200]

thats what i said.... few more words but... anyway...

 

[omslaw]

Do a search for Marble Mod and/or PAIR valve mod. The marble mod would be easy for you to do - just raise the fuel tank, disconnect a hose from the airbox, stick a marble in it and reinstall everything.

 

[turb06LE240]

Pair valve mod, Marble mod, PC3USB, KN air filter, and custom map--- Make a day out of it

Hey maybe throw a turbo and exttended arm on it, nothing huge just 5lbs of boost and a 3 inch extension.... Just kidding, I have to agree with what everyone else said, the pair valve mod should do the trick... Get the covers and throw the pair system out {sheds a few lbs}
Most people are capable of doing it all themselves...

 

[Spudley]

Just block off the big hose on the right side of the airbox / air filter element. Don't forget to put a plug on the filter housing as well.

I was chasing the ORG boys during the Vegas run, and suffering some MAJOR Busa-embarrassment from my popping exhaust issues. Especially at 9,000-10,000 rpms in second and third. I THEN blocked off the pair valve supply line and I have a smooth / quiet Busa now. No issues.

 

[smonroe86]