jetting advice needed

[Mike Lenz]

I am jetting a 1980 125 with a 34 Bing.  This is not the stock set up so  I am doing some guessing.  right off idle it wants to die, like a properly jetted bike does when its cold.  However, it doesn't go away when it warms up.  Then just over that level it seems too lean and wants to rev up by itself a little.  I dont see where I could have an air leak, plus it doesnt seem to do it at higher revs. Running a 45 pilot and have the needle up a notch or two.  Any ideas?

[Dale Sonnenschein]

Does it have a choke? If so, try it with the choke on or partially on. If it makes it better then you are too lean. Also spray the connections with carb cleaner and see it if changes things at idle. If you hear a change you may have an air leak too. It sounds lean to me but a 45 pilot should be plenty big. Are you sure the pilot circuit is clear?

73 Jackpiner
73 Husky 360 WR/RT
76 Husky WR360
78 husky cr250
82 husky wr430
10 ktm 250xc
02 bmw r1150r

[Mike Lenz]

Dale, Thanks for the spraying tip.  I did have an air leak after all.  I used a gasket on the intake manifold between it and the cylinder and this bike doesnt take one!  It was KTM's first case reed motor and has a intake manifold that not only bolts to the cylinder, but also to the cases. The gasket left a little air gap next to the cases.
Thanks Again!

[Dale Sonnenschein]

I'm glad I could help.

73 Jackpiner
73 Husky 360 WR/RT
76 Husky WR360
78 husky cr250
82 husky wr430
10 ktm 250xc
02 bmw r1150r