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Changed to 110 runs like crap now?


mpd579

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Changed domes to run 110 when from 23 to 19 have 185 psi for compression advanced the timing from +4 to +6

 

Long story short the bike has slowed down!!!

 

I use the redneck test and tune racing to judge my performance Racing against a damn good running Raptor. On pump gas I was pulling the Raptor about 2-3 bikes going from a roll in 2nd and winding out 5th gear Now after the mods the Raptor is killing me .......putting at least 6 bikes between us

 

I can't pull him from any kick or anywhere in the race

 

I went to a 14t front sprocket and that isn't helping either (from a 15)

 

 

I've tried the jetting I ran a 150 152 155 and 158 main and moved the clip up/down several times (changing only one variable at a time) and still can't get my bike right

 

NO the RAPTOR didn't get faster LOL

 

Ideas??????

 

Plug chop looks good I don't have any pics right now but we did a few I had the bike 2 lean and 2 rich at times put its close with the 152 main

 

 

my mods r in my sig but here they are again

4 mil

HJR Hardcore MX port

34 PJS

K&N Pods

timing is +6

cool head with 19cc domes

boyseen reeds and cages

fast clutch

 

 

the pilot jet is a 42 not changed it but I don't think it matters

 

had the bike on the dyno at Waynoka when it was on pump gas My jetting was close with the 150/42/and being on the 2nd clip

 

Kevin at HJR and Jeff at FAST both say the upgrade to 110 won't need to be re jetted I was just trying for the hell of it

 

SO IDEAS? Please????

 

Forgive me I'm worn out and tired but can't sleep over the deal

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What is ur squish? Neither builder asked? Compression seems a lil high. Ur probably detonating. Who cut u the domes? Or were they off the shelf/custom?

 

 

 

not sure on the squish my buddy that put it together will know I'll ask him in the morning The domes were custom cut from FAST It wasn't Jeff I can't remember that guys name that works for him but he said that was about right with the 185

 

I'm not sure it's my 1st Shee and 1st anything I've tried race fuel in

 

thanks

josh

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Check squish, check profile, pull all the timing out and see what that does. If it seems to improve you might have some detonation issues. The pilot you have listed might be a touch on the lean side as well. I don't know much about the domes from fast, but you will get a ton of builders who all have their preference. So, I think you should definitely call HJR for your domes since he set up your cylinders. Also, what kind of fuel are you using and where is it coming from. I used to have problems with Sunoco from my local station but up the road 25 mins they had way fresh fuel that never detonated for me.

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have you checked your jetting?

 

Man I bought all those parts off you and your going to be mean to me like that???? haha yes I checked

 

I won that award from smallest pic in the FOR SALE section earlier looking for the biggest dumbass or dumbass of the year award here I should win hands down!!!

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Check squish, check profile, pull all the timing out and see what that does. If it seems to improve you might have some detonation issues. The pilot you have listed might be a touch on the lean side as well. I don't know much about the domes from fast, but you will get a ton of builders who all have their preference. So, I think you should definitely call HJR for your domes since he set up your cylinders. Also, what kind of fuel are you using and where is it coming from. I used to have problems with Sunoco from my local station but up the road 25 mins they had way fresh fuel that never detonated for me.

 

 

 

going to check the squish 1st I'll bet thats the problem but I'll turn the timing down and try that I tried fuel from 2 places I know the 2nd round of fuel is good its right next to the local race track all kinds of people buy it and run it in cars/bikes exc

 

 

we were buying some stuff from FAST and I just ordered the domes from them To be honest I had no idea the builders may do the domes differently i just thought I need 19cc domes for my 4mil exc

Like i said I'm looking for the dumbass of the year award

 

Thanks

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maybe, fuck if i remember, i thought you was talking about motor stuff, because i dont sell anything but stock parts

 

yeah I was right chain and seat I got from you

 

I think its that POS chain that caused my bike to slow down I want my 10 bucks back

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Like i said I'm looking for the dumbass of the year award

 

 

Too late, somebody else beat you to it and you'd play the rest of the year catching up.

 

Take the domes off and leave everything else the same. While changing fuel from pump to 110 shouldn't require a jetting change, upping the compression and/or the timing will.

More timing and more compression cause more heat...fuel, raw unburnt fuel, actually cools the motor when the intake charge comes in.

So...more fuel could be needed, depending on how close to the fine edge you were before.

 

Two more things to double check. Make sure your flywheel is good. Remove it..shake it, make sure you don't hear anything. Normally a bad flywheel will cause you to break up, especially at higher RPMs.

Check your wires around the pickup coil...and check the air gap on both nubs on the flywheel for the pickup coil.

 

If you don't change anything else, other than just the domes and you're right back to running good like you were...you found the issue.

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Squish, dome shape, jetting, timing.

 

If you are chopping the plug, you are missing most of the critical data regarding the ground strap and relation to ignition timing. Squish clearance is a good start.

 

I have been telling people for years to ignore the number on that timing plate and focus on how it runs. Due to several factors, they are not all that accurate. A timing light is the only real way to know what you are really getting.

 

Brandon

Mull Engineering

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