jet question

[lethal dose]

Got a '92. Has the kerker 4-2-1. Think it's k series... pipe was mfg before supertrapp was involved. Bike has k&n filter and is running the 2.25 inch comp baffle with no packing. I know it's been jetted but I don't know sizes. I have always thought there were 3 stages of jetting... 3 being with velocity stacks and individual filters. Bike runs good but I'm concerned about leanness with that huge baffle and no packing. It does crackle and POP when engine braking but I think that's because of the lack of packing. Also... crackles on initial startup but sounds fine after it's been ran. Any good way of telling if it's too lean? Read the stickys but am still a little unsure.

 

[naughtyG]

You say it's running great? "If it ain't broke don't fix it!!"

It's normal to pop and crackle and cold, and also when engine breaking with more open exhausts - I think the OEM exhaust does a great job at muting that completely.

If you wanna find out your jet sizes, you'll have to tear into your carbs.

Dynojet Staqge I is a piece of shit. Stage III is indeed jets, removal of Vboost (silly if you ask me) and individual pod air filters and oil breather from crankcase (another total waste of space IMHO).

Our Sean Morley here has done a LOT of testing, and has come up with his own jet kit that many swear by, and still uses the OEM air box with shimmed 'Y' intake.

Again, if it runs good, you're golden!

 

[lethal dose]

I was just a lil concerned. I've had 4 stroke dirt bikes that run great but burn valves... just didn't wanna run into that. So... crackle and POP while engine braking is ok? I understand the "if it ain't broke, don't fix it theory", but i don't wanna promote breakage... Haha. Anyhow, thanks for the comforting words, bro.

 

[vmax2extreme]

You say it's running great? "If it ain't broke don't fix it!!"

It's normal to pop and crackle and cold, and also when engine breaking with more open exhausts - I think the OEM exhaust does a great job at muting that completely.

If you wanna find out your jet sizes, you'll have to tear into your carbs.

Dynojet Staqge I is a piece of shit. Stage III is indeed jets, removal of Vboost (silly if you ask me) and individual pod air filters and oil breather from crankcase (another total waste of space IMHO).

Our Sean Morley here has done a LOT of testing, and has come up with his own jet kit that many swear by, and still uses the OEM air box with shimmed 'Y' intake.

Again, if it runs good, you're golden!

I thought there was only a stage I which rejets and changes out needs/springs/jets and then stage VII which removes vboost with velocity stacks and individual filters?

 

[naughtyG]

Ya sorry I meant Stage 1 and Stage 7 - discard the III (3) in my post.

LD, the best way to have a look at whether you're running lean or rich is to look at your spark plugs - if the electrodes are overly white then you're lean. As usual the nice light tan color means it's running fine!

Usually the popping on descel is also associated with air leaks in the exhaust system - check all four headers are secure and not blowing, as well as the connections between headers and mufflers.

Mine's been popping a little on descel ever since I went to Supertrapp slip-ons, and then the Jardines I'm currently running. I couldn't hear any of it with the OEM mufflers, and I made no changes to the carburation (stock jetting). I just have a K&N air filter element and slip-ons.