where to go from here. jetting q.

[Jim Cook]

I fear that you may be confusing the pilot jet circuit with the jet needle/needle jet circuit, in where it is too rich. If you have the throttle stop screw screwed in too far, the raised slide (and resulting raised jet needle) can effectively bypass much of the pilot jet circuit.

(IMO... The pilot jet controls from 0 to 1/8 throttle. The jet needle/needle jet circuit controls from 1/8 to 3/8 throttle; with the slide affecting everything; and the main jet influencing things more as the throttle opens more, and controlling the jetting from 1/2 to WFO.)

Regardless, the #7 slide will definitely lean things out a bit.

Good Riding and Jetting!

Jim
Good Riding!

[iancp5]

Jim,

What's driving me crazy is that I jet it, it runs well, then it changes on its own! I can't decide if it's my imagination or there is something else going on. How much does the weather effect it? The temp has only dropped 5-10 deg but it's gone from dry air to very wet and damp.

[Jim Cook]

Originally Posted by iancp5

Jim,

What's driving me crazy is that I jet it, it runs well, then it changes on its own! I can't decide if it's my imagination or there is something else going on. How much does the weather effect it? The temp has only dropped 5-10 deg but it's gone from dry air to very wet and damp.

10 degrees won't affect the jetting as much as the drastic change in humidity. Humid air has less burnable oxygen than dry air.

It's a compromise, but you should be able to come up with a compromise which will work in a variety of situations is a fairly usable range of temperatures and humidity.

One more thing.... I never try to experiment with jetting unless I have fresh packing in the silencer. Dirty silencer packing
throws the formula way off.

Good Riding!

Jim

[dank]

throwin a thought out there, could ur needle seat be worn? from what ive read a worn needle seat will make ur jetting next to impossible.

[iancp5]

Originally Posted by dank

throwin a thought out there, could ur needle seat be worn? from what ive read a worn needle seat will make ur jetting next to impossible.

Could be. Maybe I should bite the bullet and get a new carb. It's almost as cheap as sending it to RB from the here. Although didn't I hear that some of the older Keihin allowed replacement of the seat? Bet no-one in the UK stocks them though. I'm waiting for the #7 slide at the moment. I think the fact I'm using a 35mm doesn't help, not sure what other bikes it's used on. I can get a new 36mm for £110 though.

[stainlesscycle]

i have been completely happy with the 36mm carb. my jetting has been pretty stable 50-90 degree weather. i've felt no need to tinker with it once i got it close. it runs way better than it ever did with the 38mm carb. and it truly idles, without cranking the idle screw in/throttle adjuster... and it's way snappier off the bottom.

[Skidad]

Any of you guys with the 200's tried adding the 10mm spacer to the exhaust flange like Go Fasters recommended to help low end power?

Maybe Go Fasters (or Scotties) could fab up a kit if it works so good?

[stainlesscycle]

i run the ltr style pv cover, which i believe achieves the exact same thing as the 10mm spacer. i also have a 9 oz flywheel weight on it.

[iancp5]

Originally Posted by stainlesscycle

i run the ltr style pv cover, which i believe achieves the exact same thing as the 10mm spacer. i also have a 9 oz flywheel weight on it.

+1 Same here

[GMP]

Maybe try and get ahold of a newer 200 specific pipe. If someone has one it would be interesting to see the dimmensional differences.