Jetting Help (yea I know)

[Doibugu2]

Alright, my quad actually runs, so I think I just need a fine tuning. I rode it yesterday it is probably 70 at most. At towards the end of the day, I was starting to have some hesitation at the top (3/4 + throttle) I also fouled plug yesterday, which has never happened. It was old, and needed to be change, and came out black.

I have a HMF slip-on w/ airbox lid on. Was running a 146 DJ. Needle 2nd from top. No other mods.

I just started it up now and its around 55 and the hesitation seemed worse, not bad but worse. So I put in the 142 DJ. It also backfires a little when I let off the gas from full throttle.

Are we supposed to richen or lean when the temp cools? I thought richen.

What do you think?

are you changing the needles? or mains?

[Doibugu2]

I just changed the main.

But the needle is the dyno jet needle.

[Colby@C&DRacing]

You need to richen up the main when it gets colder out. Go up one size on the main put the needle in the 3rd groove from the top. you also need to run a 42 pilot.:)

[Doibugu2]

I am running a 42 pilot and I'm pretty sure the needle is 3rd from the top. Could be second, don't really remember.

But if I was bogging with the 146 DJ main, shouldn't I have to go down, not up? I thought that was the wrong way in regards to the weather.

[Colby@C&DRacing]

Is it a bog or a flat spot? if it is flat them you are lean is it hesitates and bags it is too rich. Make sure your filter is cleans:)

[Doibugu2]

Yea the filter is clean, but I will double check that.

Itls like get on the throttle, go, get moving, then stumple, stumple, go.

It didn't start doing this till the end of the day. And the bike seemed to be running pretty hot. But I was really reving the crap out of it.

Does anyone think the 142 DJ will be too lean to race with?

If anything I think it is too rich. It just sucks I don't have anytime to play with it, with the way work is going. I hope I can mess with it at the race a little.

[cals400ex]

i would do a quick plug chop. that should at least give you an indication. go out and floor it for a bit then pull in the clutch and kill it. check the plug. doing a plug chop won't help for fine tuning as the fuel anymore is crap but it should either give you a white color or a black color on the end of the plug if it is lean or rich. i can't even help with the jetting since you are using dynojets. when the temp gets colder, richen the jets.

[Doibugu2]

Cal, yea I'll have to try that. Just put in a new plug, and pretty much went full throttle around the block. I'll double check that.

Originally posted by Doibugu2
Yea the filter is clean, but I will double check that.

Itls like get on the throttle, go, get moving, then stumple, stumple, go.

It didn't start doing this till the end of the day. And the bike seemed to be running pretty hot. But I was really reving the crap out of it.

Does anyone think the 142 DJ will be too lean to race with?

If anything I think it is too rich. It just sucks I don't have anytime to play with it, with the way work is going. I hope I can mess with it at the race a little.

Doug with my setup I have right now,,air box lid on with no holes, I run a 146 Dynojet. So with just a slipon you'll probably be OK. When i jet i run it tillit starts to backfire when lettin off the gas at WFO, then go up one size and I leave it at that..

[Doibugu2]

Originally posted by Rico
Doug with my setup I have right now,,air box lid on with no holes, I run a 146 Dynojet. So with just a slipon you'll probably be OK. When i jet i run it tillit starts to backfire when lettin off the gas at WFO, then go up one size and I leave it at that..

I was getting worried, that the 142 was going to be to small. But I think I was running a little rich before, but I just never checked. So with what your telling me, I probably was rich.

I'll leave the 142 in and hope for the best. I cleaned my filter which wasn't real dirty.