Hey guys just bought a 400 scrambler with a couple mods done. Bike has HPD Trail Pipe, HPD Silencer, HPD aggressive clutch kit, V-Force Reeds, Reed Spacers. The bike had the piston broke in half when I bought it, and I just got it all fixed. The mechanic bored the cylinder .040 to clean up any damaged and ported the cylinder.

First question is, mechanic wants to know factory squish clearance so he can mill the head a little, anyone know the factory squish for a 2000 400 scrambler.

Second question is, anyone know the suggested jetting for this bike with the HPD pipe on it. It has the stock 34 mm mikuni carb still on it.


Thirdly, what kind of injector oil do you guys reccommend. I have some Amsoil left from my snowmachine this winter and was thinking about using it.

thanks

kyle

 

jetting should be 260-270.

there was a recent discusion on here regarding squish you may want to try searching for it I can;t find my notes. the factory head can be cut 0.020 thousands and still run premium pump gas.

careful letting him port it instead of sending it elsewhere if he has never done a polaris 400 before he could mess it up pretty easy. what are the specs he is using? he should be willing to release this information to you.

 

260 jet should work great. I use the polaris gold synthetic oil. Seems to work just fine. What kind of Amsoil do you have left, I was gonna switch over to the interceptor because it seemed like good stuff but I still have some polaris oil to use.

 

the oil i have is interceptor, i have a couple of galloons left from the sled from this winter. Seemed to work great this winter, I think I am going to give it a try in the bike.

thanks

 

260 sounds right, thats what i'm running with almost the exact same mods.
Maybe even raise the needle 1 clip position, i can't remember for sure.

Jim

 

I have the interceptor too, dont mix it onto the old oil, drain the old oil first.

Jim

 

Is there a specific reason for this, or do you just not want them to mix.

 

this is a really rough way of putting it...but think of it as mixing deoderants(sp) or colognes.

 

most places i've read said not to mix oils, you can change from one to the other but run it low or drain the remainder of the old oil first.

http://www.motor-oil-engineers.com/c...tadditives.htm

http://www.motor-oil-engineers.com/

" the oil company has carefully engineered and blended the chemicals already in the motor oil ... "

 

Hey guys, thanks for all the help


Just went for my first ride on the bike today. I ended up going safe and putting a 270 main jet in. Definitely not lean, the plug was black. I am mixing oil in the tank also, just to be sure the oil injection is working properly.

Performance wise, I thought the bike would be a little crazier. Don't get me wrong, its quick, but just doesn't seem to be what i thought. It's my first time on a scrambler and I am not sure what its suppose to feel like stock or modded.

Basically I only have a few more questions, can anyone tell me what max rpm is for a 400 with hpd trail pipe/silencer, shaved .020 head, mild porting, v force reeds, etc. HPD website dyno looks like about 7000, its awfully hard to tell by riding it without a tach.


jimmypsp700: thanks for the help, you do have almost the same mods as me. Do you have a tach on your bike? I am in the process of trying to acquire one right now. I am just curious as to my max rpm right now. It looks like hpd says the bike should run about 7000 rpm according to our mods. Do you know what yours runs. Is your primary clutch spring red with yellow stripe. I have yet to take my primary or secondary apart, but i know my spring is red and yellow.

thanks