Need help everytime i get on da gas slow the bike seems to ride ok but when i get on it hard seems to not sound rite and backfireing alot?? Dont know were to start it has new sparkplugs... im thinkin a vacume hoes is disconected or i have something on the wrong way??? if its backfirieng i can only think its running a bit rich and dumping to much fuel.. it spits a 12 inch flame when i get on da highway my buddys say yea seems cool not cool i just want this dam thing to run rite..? whats a common mistake to have on backwards that this can happen any ideas>>??
Rey

 

Did this only happen after you did something to the bike?

If its after a plug change, did you put the proper type plug in? If you used a cheap plug or improper one, it won't have enough spark output and could lead to your issue.

How many miles are on the bike? If the mileage is in the upper teens, thats a common sign of the bike needing a valve adjustment.

If it is running too rich, it could be the FPR going bad.

 

do you have a power commander? cause it sounds like you have a bad map...

 

So you're having an afterfire? Backfire is combustion coming out the intake side, afterfire is coming out of the exhaust. If it's doing that while you're on the gas, you have problems. Mess with the timing at all? Running high octane fuel? Happen hot or cold? Fuel delivery problems create driveabilty issues, but I've never seen one cause afterfire. I say most likely timing or valves. The PAIR emmisions system also will cause afterfire problems if the reed valves are failing, but that happens when you're letting off of the gas.

 

so i changed the fpr regulater and it keeps backfiriing but not as bad as before im think i need a valve adjustment or timing is off..? but what has me a lil stumped is there was a hose leading to no were under the tank and read tb1200 im thinking could be a vacume dis conected from the throtle body or somewere else if any u guys know be very apprecitaed and i have another engine wit to pairvales i can try swaping em out see if dat helps>? DO any of u have the servo wires disconected from the servo or the htev or flap mod done cuz i removed the airbox wire from da servo now i got fi light on and blicking red light 4 blinks fast 3 slow im just going crazy....

 

I had this problem on my zx6e and just turned out to be the battery terminals were loose so when i throttled it the wires were moving slightly loosing the connection, then it connect again and caused a massive bang spitting big *** flames out the exhaust im guessing you would have checked the battery but if you havnt worth a check ?? Mine turned out that my connections were just to loose by like 1 or 2 turns but there was still enough power for the lights to stay on when it lost the connection.

But my best guess would deffinetly be the timming

It shouldnt be over running that bad with just the map being set up wrong.