Still Backfires...

I have an 03 XR650R with full Moriwaki S/S exhaust, stock airbox, running 68 and 175 main woth needle in 3rd position. Well the thing is still backfiring upon deceleration.

Would you guys recommend going to the 4th position or just keep going up on the main?

thanks

First Pull the snorkel and plastic insert restrictors from your "stock" airbox. Then I'd toss in a Uni filter. Next if you have the stock needle put the clip in the 4th position down. Depending on your location and temperature, your jetting should be fine. In the summer I'd run the 175/68s, but in winter, below 50* I'd run a 178 main possibly even a 70 pilot. Give us some more geography info as to where you live. Once you change the clip position, check that your fuel screw is 1 1/2 turns out from "lightly" seated.

First Pull the snorkel and plastic insert restrictors from your "stock" airbox. Then I'd toss in a Uni filter. Next if you have the stock needle put the clip in the 4th position down. Depending on your location and temperature, your jetting should be fine. In the summer I'd run the 175/68s, but in winter, below 50* I'd run a 178 main possibly even a 70 pilot. Give us some more geography info as to where you live. Once you change the clip position, check that your fuel screw is 1 1/2 turns out from "lightly" seated.

I live in Southern California, so it's sunny and warm all the time and I'm about 75ft from sea level, according to the GPS. I did forget to mention though that the fuel screw is 1 1/2 turns out. I'll do the airbox mods tonight. thanks for the info Tim! :cry:

Well is this bike a California model? Then you would have all the emissions junk on it too. That needs to go. However, I'm not familiar with that apparatus. If you're at sea level or just above 175/178 main and a 68s w/ the stock needle in the 4th clip should be fine. Good luck, let us know how you make out. For future reference check out this site The Pig Pen . Our BRP Guru Qadsan developed this for us Pig junkies. Seems to have worked for me so far. :cry:

if all your uncorking mods are done try a 178 main :cry:

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now