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Discussion Starter #1
I rode with another 2001 800 this weekend and
tried out his sled. He was running a stock head
and 470 mains. I'm running an RK Tek head and
420 mains.

His sled was much crisper on top end than mine.
I know I could jet down further and be safe as
my EGT's were only running around 1100- 1150
in WOT.

The problem I have is midrange. The EGT's creep
above 1275 when running 5.5 - 6.5K rpm's under
moderate load. I've got the jet needle shimmed
to where if I had an e-clip it would be between
the 4th and 5th notch. Not much help.

Does anyone know what needle jet is in the sled?
Has anyone tried changing it? What were the results?

I want to be able to jet down my main some more,
but I don't dare to because of the midrange. I
need to get that under control first.
 

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gunner, leave the needle and seat stock, also no need to shim it put it back where it was stock. my guess is that your sled is running out of fuel on top, 420s are pretty low unless your riding in 50 degree weather. kelsy at rk-tek says to down jet with his head 1 to 2 sizes but do a plug check.you should be running a 6 hole base gasket with that head unless you had him set it up for something different.i would also guess that the shim you put in is causing the higher midrange temps combined with the 420s.what other mods do you have done to your sled.
 

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Discussion Starter #3
Its not running out of fuel as I've jetted down
step by step and EGT's are slowly rising. When I
choke it it slows - not a sudden burst. I know that
I could run 400's. Kelsey did tell me that one of
his customers is using 380's but I assumed that
would be high altitude riding.

The shim should richen the sled slightly, but doesn't do
much. I know others that have lowered it .015 from stock.
I've been back through my clutch tuning book a dozen
times now just to recheck what I know.

I'm going to check all the vent lines to the airbox on
the weekend. Maybe something there is kinked or
melted slightly causing the sled to richen.

Keep the ideas coming. This is driving me crazy.
 

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If you have DPM is it leaking? I've heard of this problem, thus not putting enough vacuum on the float bowls and causing a rich condition. I have heard of guys sealing them with silicone. You can check them with a mini-vac.
 

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Gunner,

Have you adjusted your fuel screws to 3.5 turns.  This is needed to help the idle down, when doing so you will have to adjust the idle stop screw.

Damon
 

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Discussion Starter #6
I don't have DPM so its not there.

I'll check my fuel screws. I don't have any
problems with idling down or idle in general.
I did last year, but not this year.
 

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I just went from a black plug( running rich) to a white plug(lean condition verfied by EGTS) and all I did was to repair a bind in my oil pump lever.It lets be believe that oil settings affects the richness of the fuel. This is on a tripple as all clyinders were affected.There isn;t enough snow in ILL. to verfy oil pump setting verses consumption.I have jetted up 2 steps to overcome the condtion
just a thought.
 
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