dynojet carb jetting

[patrick97war]

ESo i hope i got the right size main jet in the carb in live in nashville tn i have the 140 main jet is the correct?

 

[Gen1Pat]

Stock is 145.

 

[bones]

gen1 dyno jets have different number than stock style

 

[Gen1Pat]

Oops, forgot he said that in his thread title. My bad. But stock is 145. I was half right! lol

 

[bones]

lol sure are lol

 

[patrick97war]

Well i have the dynojet installed in the carb just trying to make sure i have the correct jet for the

 

[bones]

you'll have to try it and see ... do a plug chop

 

[patrick97war]

Whats a plug chop?

 

[bones]

HOW TO JET - THE BASICS
Plug reading doesn’t work. Revving the engine while it’s sitting in the garage doesn’t work. Other than Dyno testing, the steps below are the only way you can consistently jet your engine.
1. Find a gentle slope that you can ride in 2nd or 3rd gear. Look for something that will put a decent load on the engine. This will be your tuning test area.
2. Make the recommended jetting changes. Always start rich and work leaner.
3. A basic outline of which jet is active at a particular throttle setting:
Pilot Jet = 0 to 1/4 throttle. Needle = 1/4 to 3/4 throttle. Main Jet = 3/4 to Full Throttle.
● Changing the Main Jet size won’t affect how your engine idles or runs at 1/4 throttle.
● Engine RPM isn’t what determines which jet is active - only throttle position does this.
4. Start and warm up the engine, then ride your ‘test hill’. Any point where you feel the engine stumble or hesitate indicates a rich condition. Note the throttle position and modify the corresponding jet (1/4 to 1/2 throttle = leaner needle. 3/4 throttle or more = leaner main jet).
5. Only change jetting by 1 step at a time, and 1 circuit at a time (don’t change needle and main at the same time). Re-check after every change.
6. Once the engine runs smoothly throughout, you’re jetted!
If you ever notice an abrupt change loss of power, or engine sounds changes, shut it down.


(this was pulled from the powroll website)

you should really read this thread
http://www.yfm350.com/forums/showthread.php?t=21231

and this one
http://www.yfm350.com/forums/showthread.php?t=15050

 

[patrick97war]

Thank you for the help i will do so let you know the out come