Question about back-firing...

[coke4class]

So... Lately my bike has been backfiring alot... it seems it is only when going from first... second... and to third gear.... all the gears upto third, I am hearing "plap....."-- of backfiring.

Also my buddy told me yesterday that when I was downshifting... it was shooting flames sporatically.

I use regular unleaded 87 gas...

My bike is 2006 Busa of course...duh... and has just the Yoshi R22 exhayst on it. About 4050 miiles on the bike...
Could you guys help me find solution to this backfiring...?

Thank you in advance guys!

 

[05BusaLe]

Did you remove the pair valve and install the block off plates?

 

[coke4class]

no... i didnt do any modification to the pairvalve nor the blockoff plates. I have been reading some of the past forums and came across the marble thingy. Does it work...? Is it safe... will my bike blow up one day due to marble mod thingy... if so... i am a bit scared to do it... however what is the most effective and safe way to go about this backfiring issue... it just sounds ghetto when i shift up 1..2.. 3rd and it goes... PLAP!

 

[05BusaLe]

Do a search on this board for the marble mod it works and is safe, that is the cheapest way to fix your problem but for about $20 and 2 hours of your time you could remove the pair valve and install the block off plates. Save some weight! You could pm the board sponsors for a price on the kit!

 

[coke4class]

What exactaly does the pair valve do... and by removing it what would it do?
From what I know pair valve has to do with returning the source... etc... am i correct or just talking gibberish.

If I choose to do the pairvalve removal and installed the block off plates... is that the ideal way to do it over the marble mod...?

What would you do Mr.Busale...?
I love your pipe... how is the HMF... and does it sound?

Thank you so much for your help

 

[05BusaLe]

The block off plate is the way I went to save weight and prevent the back firing. The pair valves job is to inject air in to the exhaust stream to help burn up unburt gases. With your aftermarket exhaust system the bike will run richer and more fuel will be dumped in to the exhaust hence the backfiring! You should also consider a power commander and custom map for your bike, you also would benifit from a K&N or BMC air filter (more air in more air out) The HMF sounds great, not the loudest but it performs very well and it looks so dang sexy with its carbon cans!

 

[PDBusa]

Marble mod has worked for many. Just be sure you have correct hose plugged. I have RS-3's and never had backfire. I just installed a PCIII to smooth out lower rpms and still don't have back fire.

I'd try the 20 cent marble mod before digging into the pair valve unless you are going full system.

 

[heavybusa]

Definetly do the marble mod.

 

[8Daytona8]

Could it need a TB sync ? Stock with no mods, these run great with no popping or backfiring!! Got to be unburnt fuel in the header rite

AOL.com Images Not Available

 

[rockadaous]

pair mod. I just picked up my block off plates yesterday. Just waiting on the cans now.

 

[BusaBlaze]

Does the FL DMV test exhaust emissions for vehicle inspections? If so, your bike may not pass without the PAIR value operating. The “marble modâ€￾ is easier to reverse for inspection purposes….

 

[OZZY]

i too had some crazy, but cool, backfiring on decel after i installed my yoshi RS-3's. i stuffed a marble in the beast and the backfire is gone. takes a whole 5 mins to do. id say try the marble mod first, then when u are ready for a pc and map, go ahead and do the block off plates. either mod will give u the same result so now u just need to decide which one u want to do...

 

[bigoltool]

(heavybusa @ Feb. 28 2007,08:34) Definetly do the marble mod.

Cheap, quick, effective! What more could you want?

 

[heavybusa]

(bigoltool @ Feb. 28 2007,21:30)

(heavybusa @ Feb. 28 2007,08:34) Definetly do the marble mod.

Cheap, quick, effective! What more could you want?

My favorite kind of mod.

 

[The Big Red One]

(coke4class @ Feb. 28 2007,08:00) no... i didnt do any modification to the pairvalve nor the blockoff plates.  I have been reading some of the past forums and came across the marble thingy.  Does it work...? Is it safe... will my bike blow up one day due to marble mod thingy... if so... i am a bit scared to do it... however what is the most effective and safe way to go about this backfiring issue... it just sounds ghetto when i shift up 1..2.. 3rd and it goes... PLAP!

Do the marble mod....its easy, fast and will make your bike run smooth as silk with no more backfiring

 

[toolmn]

A power commander should fix the problem with a proper map...I too had backfiring on my old busa until i installed the pwr commander...

 

[dadofthree]

Good info as usual

 

[Nekosohana]

Straight Pipe with the Marble Mod, and no backfiring at all.

 

[mospeed]

yup do the marble mod. I did and I have no backfiring (full yoshi), but i do have a somewhat rough throttle from idle to 3000rpm. a bit jerky, so the next thing will be the PCIII

 

[dmrowe]

My Webpage

This link explains what a pair valve's purpose is. By now with all the responses you have received you know what you have to do. Just thought you would like to know what the purpose of the pair valve on a stock motorcycle is.