440 Sparks CRACKLE??

[starky]

Does anyone else that has a Sparks X6 pipe nad 440 kit have a crackle when letting off the gas at high RPM's. Is it natural... I see these pipes are slip fits so maybe they leak a bit.. Let me know

[Mofo Racing]

I just got my sparks pipe and I notice a "crackle" but I am still running on my stock jetting. So you might want to double check your jets

[muff]

is it like backfiring a little bit? your main/pilot jets are prolly a little lean

[DantheEXman]

I have a sparks and It crackles and pops when I let off.

I had it jetted a little rich, still did it, then I leaned it out and the plug is perfect, still does it.

I cant figure it out.

[quadmx7]

i noticed today that mine had a little crackle too when i let off the gas, only 2nd time i road it with the sparks pipe. im running a 180 main and am going to try a 185 on my 426

[starky]

i have hotcams, no lid, 39 FCR, and am running a 55 pilot, 188 main, i have tried leaner and richer jets but it still does it,it just like crackles when i let off the throttle at high RPM's. It doesnt really backfire or pop loud, just crackles pretty good....what is everyone else running for jets that has an FCR.

[muff]

I'm running a 426, 11:1 comp, hot cam, sparks X6, FCR 41mm, 172main and 52 pilot, UNI air filter and no airbox lid. sounds lean compared to your guys's setups but it works for me

[cals400ex]

Originally posted by muff
I'm running a 426, 11:1 comp, hot cam, sparks X6, FCR 41mm, 172main and 52 pilot, UNI air filter and no airbox lid. sounds lean compared to your guys's setups but it works for me


yeah, but yours will run better than theirs too with the smaller jetting. i only ran a 165 in my 406. my buddy runs a 172 in his 406 and it is a tad big.

[muff]

with the jetting not so rich the quad will have a lot more snap and improved throttle response :cool:

[quadmx7]

yeah but with a jetting too lean u'll rot ur pipe out eventualy and foul alot of plugs.

[muff]

Originally posted by quadmx7
yeah but with a jetting too lean u'll rot ur pipe out eventualy and foul alot of plugs.

yea but thats the thing its not running lean at all. no hesitation anywhere in the power range, and it doesnt studder or backfire after throttle release. the best way to jet is to lean out the quad so it barely backfires after throttle release, then increase the main jet a size or two

[starky]

the pipe can crackle also when it is too rich, because it is the ecsess fuel that is popping in the pipe... I know from experiance.. But i was just having hte trouble of it popping no matter what, i was also wondering what people are running for jetting and A/F screw on their 440 kits.

[xc400ex]

The crackle your talkin about won't be fixed by the main jet, bump the pilot jet up one size and see if it doesn't go away.