My Kx 85 Things

[THEcomeBAKIDKX85]

HI GUYS

My kx85 broke about 4 months ago and i had it rebuilt. We bored it to a 100cc opened up all the ports. It was basically modified all the way. I took it to the track and it was flying to me nd i got the air box opened up by molding little like shark fins on the side and it seems better but a racer came to me and said that the jetting is too high. I checked the standard jettings and a 85 has a 140 mian jet and a 100 has a 138 ...... now my bike has a 135 ............. please help me out with that... surely the more fuel going in means that it would sound like a dog howling and with less it should scream .... please help im confused

jaden :ride:

 

[Ol'89r]

.... please help im confused
jaden :ride:

You certainly are. :nod:

To find your correct jetting you will have to do a plug chop.

Do a search on this site for 'Plug chop' or 'Reading a spark plug'. There are many threads that discuss this in great detail.

Also, please don't post the same queston more than once. Be patient, someone will answer your question.

 

[SAPPER]

First, the 85 has a bigger main, BUT, it also has a different needle. If you're running the 100 needle, use this chart to help you out.

http://www.thumpertalk.com/forum/showthread.php?t=691089

 

[helio lucas]

do never thrust on charts like this, they are a great base line resource but not definitely the end of the road. not only engines differ slightly but they will wear out. needles wear out. different pipes have different needs. reeds make a HUGE difference.
point made, the correct way to tune a carb is the posted by OL89r. use the chart as starting point and go from there. :cool:

 

[THEcomeBAKIDKX85]

thanks guys.. i shall try this