as you all my remember last week i had some problems with my scrammy 400 hpd race mod with the pwk kehin carb. As it tures out I might have fixed it. I changed the needle and seat and got a new eeg slide needle. This seems to have helped,but I still think that it runs low on fuel on top end. heres why I think this---I never hear of anyone who has this set up and runs a higher then 180 main jet,well,i have a 185 main and the egt still climbs up to 1300 quick . the bigger the main the longer it take but no matter what jet i've ever used I still reach a temp of 1300 or higher which has melted this quad before.With in a 1/2mile run it will reach these temps.I know the egt is right,I had it fixed up with new probes and recallibrated by digatron.I can run around at 3/4 thottle and the temps will settle out some where between 1000 and 1200.as soon as i go wot it is there at 1300.
also since putting this eeg needle in and the needle and seat the whole power from mid to top seems flatter then it use to.
Could the clutching have changed because of a better running engine?
Do any of you think that a fuel pump will help?(I got one)
I have thottle plates to put in , do you think in should use them,are any of you?
I've been using this thing for drags and fire trail racing,whats the best set up for this carb? (pretty much wide open all the time),
I have a 6.5 slide with a eeg needle in the forth spot rich/down,a 185 main,35 pilot,and I have a dail-a-jet all the way rich.

what am I doing wrong here?
Why do I seem to be the only one with these problems.

 

Matt did you check the strainers on the fuel fitting in the tank, maybe you got some trash in there. I also put a stock banshee fuel valve on mine, it's a 1/4 in instead of 3/8. I'm running the powermaxx and I'm only running a 192 main in about 75 degree weather at about 1000ft eleveation!

 

I have run up to a 190 main when i had the FTR pipe,is your timing advanced ,are is it retarded 2 degrees like HPD recommends.I almost always went back to stock timing.

 

you might remove the gas tanks then take out the spark plug and look
the pistons wash as well,it will tell right out what happen down there,
wash must be black (no stick) all over with just some white loop
where the exhaust ports.i run a hpd race mod with pwk 39,170 main jet
temp is at 1175-1190,EEG needle 6.5 slide.
if the plug and piston wash do look perfect and there no bug all the way through,1300 is the right temp for you.
remember to put exhaust sensor 5" from the piston skirts for accurate reading.

 

sorry I didn't get back to you all faster,Work sucks!! anyway I haven't looked at the fuel tank latey,so maybe there could be some trash inside. I have tried a larger fuel hose. My engine is retarted 2degrees.It has a fresh piston in it with 200 psi of compression,is that right?The piston is .80 over stock.The whole quad was just rebuilt ,new bricktucky frame ,tranny,clutch springs,clutch belt,and many more parts.

The lastest up date on how it rides shows that it is still lean on the top but it did take longer to get to 1300.It dosen't brake up anymore,however,the clutching seems different.It shifts out at 7000. the question is- if it is running better now and the clutching was set when it wasn't quite running right would it change everything. it seems to me that I need lighter weights to reach 7500 or more???? Also, lets not forget the fact that it will smoke most quads in a 1/4 mile drag(it wastes my pred!!) the problem is when it ride though the sand dunes and down fire trails or any long riding at top end.

any more ideas???