cam question

[DoPeExRiDeR20]

Im lookin at upgrading my bike a little and i was wondering if i should get a new cam..... would this be a good thing to do? what will it help with and what kind should i get???? thnx to all

[DoPeExRiDeR20]

u all talk about cams all the time.. i need sum help comon.....

[Steve-o 400EX]

First let us know ur current and future mods and what kind of riding you do and that will help us out.;)

[bmw500hp]

I can't remember exactly where Hagerstown is but I do know that you have great engine builder nearby. Mickey Dunlaps "Four Stroke Tech" shop is only 15 minutes outside Lavale. He does ex engines there from basic to 500cc strokers.

[DoPeExRiDeR20]

mods-

1. WHITE BROTHERS race series exhaust
2. RENTHAL 14 tooth front sprocket
3. ITP holeshot tires all around ( front-23x7x10; back-22x11x9 )
4. ITP .190 aluminum wheels all around
5. DG full body skid plates (body, swing arm, a-arms )
6. DG front bumper
7. RENTHAL twin wall bars
8. ACERBIS rally pro hand guards
9. PRO GRIP grips
10. DG nerf bars
11. CEET white brothers seat
12. QUAD TECH carbon fiber hood w/ scoop ( w/ billet grill )
13. PRO DESIGN kill switch
14. WHITE BROTHERS rev kit
15. OUTERWEARS shock covers ( front and back )
16. MOOSE clutch and break lever w/ built in grip
17. Micro halogen race series car lights, modified to fit using fender braces
18. K&N air filter
19. 6 inch holes cut in air filter lid
20. Shaved front fenders
21. Black painted a-arms, exhaust pipe guard and sub-frame
22. Polished engine cases, battery support, throttle cap
metalic silver paited start control, brake fluid holder

I do a lot of trail riding! but ive done a lil mx and hoping to do a lot more soon...

I know sum of these mods dont matter ut i put em' all anyways.... hope ya can help.... thnx

[Steve-o 400EX]

I think with the mods you have, a hotcams stage 1 would be good if you want a cam. Do you plan on doin any motor work??

[DoPeExRiDeR20]

Yeah i want to, that was why i was asking about the cam..... i just wanna do enough to be able to feel a nice diff. in the power/speed..... i just dunno were to start out w/ engine work and mods....i live in maryland and the temp. is always diff. all year around so when i start doing engine mods and jet kits and all it get to be a pain in the arse cause im always having to tune it up.... but anyways thnx for the help.....if ya got any other advise for engine mods your welcome to lemme know

[Steve-o 400EX]

If you just go for a standard bore high compression piston, XR head gasket and hotcams stage 1, you would be runnin pretty good and you wouldnt have to spend a lot to do it, maybe $300 to do all that.

[sparks400ex101]

mine came in im runnin a hotcam stage II with a JE piston

[DoPeExRiDeR20]

weres the cheapest place to get all of that?? with the high compression piston, is that all its called or does it have a technical name? which one should i get???

[Steven]

You can get a hotter cam but they work best with a higher compression piston.

See, the hotter cam will keep the valve open longer which allows more air to fill the cylinder, hence increaseing the volume of your engine's pumping action (volumetric efficiency).

Problem is, as the valve is held open longer, it is more difficult for the cylinder to maintaine pressure. Therefore, the best combo is higher compression piston and cam. They work together to increase your engines breathing/pumping/cylinder filling action and that equals POWER.

Your engine runs about a 9:1:1 compression ratio now which is suited to the factory cam. A hotter cam will work better with 10.5:1 to 11:1 piston. Many companies make them. I think the Ross and JE are among the best.

Figure $130 for the piston and $130 to $250 for the cam. Its best to get new rockers to ensure the lingevity of the cam... they are about $90.

Thats the best way I know how to explaine it.

Steve

[DoPeExRiDeR20]

thnx man tht explains a lot...

[Steve-o 400EX]

Well said Steven. That is all true. I'm not sure what year ur quad is but if it is new you should be able to get away with not putting in rockers. I recommend the Ross and JE pistons, stay away from wiseco, their claimed compression ratios are not what they say, If they say its 11:1, its more like 10.5:1. You will definately notice a difference with the cam and piston combo.

[DoPeExRiDeR20]

is a 2001 model new enough to not have to get rockers??

[Steven]

you'll have to look at the rockers to know.

you can use your existing rockers if they are still smooth

ask your self this... what will last longer, a smooth surface rubbing on a smooth surface (new cam/new rockers) or a smooth surface rubing on a rough one (new cam and worn rockers)??

thats the idea with new rockers to go with a new cam

just check the condition of your existing rockers

[Steve-o 400EX]

Originally posted by Steven
you'll have to look at the rockers to know.

you can use your existing rockers if they are still smooth

ask your self this... what will last longer, a smooth surface rubbing on a smooth surface (new cam/new rockers) or a smooth surface rubing on a rough one (new cam and worn rockers)??

thats the idea with new rockers to go with a new cam

just check the condition of your existing rockers

Yea, exactly, you will have to use your judgement on how worn they are. When you look at the old cam and rockers you can see how they wear. When you take it apart you will see what i'm talking about.

[MillerTime]

here is a stupper for you guys, do you have to bore out the cylender head, in order for you to use a higher comp. piston,
I'm in the same boat looking to do some mods to the engine but not ready to bring the motor to a machine shop.
race mx what is a good set up, cam and piston combo.
I just bought a edelbrock carb to.

[Mr_Bub400ex]

u can get higher compression pistons for a standard bore. i do believe that the JE and Ross are lighter too which would mean u rev faster. a good drop in cam would be a hotcams stage 2 for mx stage 1 for xc or a TC cam of either mx or xc. depends what u ride.

[wilkin250r]

Pay attention to the type of cam your are getting. The Hotcams (brand name) are drop in cams, and I'd reccomend new rockers, but you can get away with your old rockers. The Webcam (another brand name) are hardwelded camshafts, and you will need to hardface your rocker arms, roughly $65 each.

If you use a hardweld cam without hardfacing your rocker arms, you will destroy them. If you use hardface rocker arms with a drop-in cam, you will destroy your cam. Be sure to know if you are getting a drop-in, or a hardweld camshaft.

[Steven]

this is true. i ground up my rockers with a white brothers track cam.

i got new rockers and a hotcam stage2 to replace the mess

on the piston, no you don't need to rebore. but why not? more cc's and a better fit = more power

[MillerTime]

at the moment I don't need to, plus that is one more thing I have to wait for:muscle: