Author Topic: where do the jets hand off?  (Read 1094 times)

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Offline phil71

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where do the jets hand off?
« on: June 20, 2011, 01:01:29 AM »
got a K1, which is running great, but under 4k rpm it seems to stutter a little. Actually, let me be more specific: If I'm actually accelerating, it's smooth as glass at any RPM, but at a 'cruise' (meaning a bit of equilibrium between power and coasting) it's kind of choppy under 4k rpm. If it's on the pilot jets under 4k, I'm thinking sync, and/or idle mixture screws.
  if it helps, i get some light exhaust popping and 'burbling' on decel in gear, but not if i yank the clutch in.
  In the past, I've had bikes with exhaust mods that acted like this, which would indicate a lean condition, but these HM300s are tight, and even, everything is bone stock.
Any ideas will be entertained. Thanks!

Offline Jon

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Re: where do the jets hand off?
« Reply #1 on: June 20, 2011, 01:48:24 AM »
With engine off wind on full throttle & mark grip against switchblock, close throttle & mark again, split this into 1/4s.

This chart will then give you a pretty good idea what to adjust for a specific throttle opening.

« Last Edit: June 20, 2011, 01:51:04 AM by Jon »
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Offline flybox1

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Re: where do the jets hand off?
« Reply #2 on: June 20, 2011, 07:42:53 AM »
i would immediately attack my carbs, cleaning them, and after all other tuneup procedures were completed, id do a vacuum sync. this'll probably take care of the s-t-t-t-t-ttutter.
add a little seafoam to your next tanks of gas.
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Offline phil71

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Re: where do the jets hand off?
« Reply #3 on: June 20, 2011, 08:02:35 AM »
The carbs are as clean as they're ever going to be without a time machine . I think it's sync, which I did a few months ago, and just now realized I didn't lOck two of them down properly . What's funny is that, at the time I was unable to trust all my adjustments because the exhaust had holes. Now it's running like an animal, just with the slight stutter . I'll break out the ole gauges and go over it.

Offline Bodi

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Re: where do the jets hand off?
« Reply #4 on: June 20, 2011, 10:06:03 AM »
Hmmm.
What's a "Straight Dia."??