Author Topic: Lag gets worse as heat goes up  (Read 569 times)


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Lag gets worse as heat goes up
« on: May 15, 2003, 10:49:39 AM »
On my 82, the "lag" about 4000 gets worse as the bike gets hotter. I have tuned it to the point that the lag is all but gone up to about the 1/2 way point on the temp guage, but if the bike gets hotter than that (traffic, passenger, etc..) the lag gets a LOT worse.
The bike has no YICS, 135's, and the carbs are as clean as a Nun's vocabulary.
I live at about 5000' elevation.
Any ideas?


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Re: Lag gets worse as heat goes up
« Reply #1 on: May 15, 2003, 12:52:34 PM »
The YICS is a critical piece of equipment (although some disagree) it's purpose is to inject a bit of mixture in a swirl pattern in the combustion chamber promoting a faster flame front & cleaner burn.  I would try to get my hands on one.  if no one has one to seel, I do have one i'm keeping for a spare i'd be willing to part with for the right price :)

another option to consider re adjustment of the flapper door.  the vacume pot that opens the door has slotted mounting holes. you might try adjusting that and see if it helps.

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Re: Lag gets worse as heat goes up
« Reply #2 on: May 15, 2003, 04:46:16 PM »
Poor runing when hot means it's rich. Check the low spd. screws, 4 turns out is a start. Also try sliding the flapper actuator back as far ar possible. This will open up the flapper a little. Also what do you mean by clean? Did you  "dip" the carbs?
« Last Edit: May 15, 2003, 04:47:33 PM by jasonm. »
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Re: Lag gets worse as heat goes up
« Reply #3 on: May 16, 2003, 09:46:59 AM »
the carbs were removed, dissasembled, soaked in Berrymans overnight, etc... Very clean.
I will try to adjust the flapper a bit. I was mostly wondering if folks thought it was a rich or lean problem.