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View Full Version : MX motor setup.Suggestions..



baker400ex
03-22-2008, 09:32 PM
I have a 07 450er. The motor is completely stock w/a sparks exhaust,sparks filter,and sparks jet kit.

I was wondering what kind of cam everyone was running.
I was looking at the Baldwin mx cam since i didnt see any other cams specifically designed for mx.

Also I've heard that changing out the piston in the 06- throws the relability away. What compression/brand is everyone running ??

and what kind of race gas is everyone running w/this set up??

Plz and thanks for any advice

Nick110
03-22-2008, 09:37 PM
Look into the CRf dirtbike cams. They are the same thing as the HRC cam and work well.. I believe 03-05 crf cams are the same as the 06-08 HRC cam.

For a piston look into CP 12.5.1. I run c12 with this set up.

pro-rider46
03-22-2008, 09:42 PM
sparks makes a cam for mx, but its pretty expensive i believe. web cam makes some great cams, and also hotcams stage 2s are very popular.

www.sparksracing.com
www.webcamshafts.com
www.hotcamsinc.com

check them out.

Dave400ex
03-22-2008, 09:50 PM
Web makes some good cams for MX. If your going to run race gas you might as well get a 14:1 piston. I would look into head work. You'll notice a huge difference there.

BlaineKaiser450
03-22-2008, 10:22 PM
id get an 02 crf cam, and one of Chads 14:1 pistons, and some head work

GIXXER1KR
03-23-2008, 03:38 AM
Web 943 and 14:1 piston and HD valve springs.

Jersey450R
03-23-2008, 07:29 AM
i'm running the HRC cam. not really fond of it for mx. too much up top and not enough bottom for the little things. on a longer mx track the hrc would be great, but on a tight track, go w/something different.

baker400ex
03-23-2008, 09:01 AM
How much is one of chads pistons...I've heard alot and i would love headwork but the season is getting very close and i dont want to be held up.

Also how is the reliability on the piston. any brands better than the other. I hate to rip my bike apart in the middle of the season to replace rings when it can b avoided from the start. thats sorta why i was alil iffy about getting a piston. and is EVER cam required to have HD springs?

baker400ex
03-23-2008, 09:08 AM
Originally posted by Jersey450R
i'm running the HRC cam. not really fond of it for mx. too much up top and not enough bottom for the little things. on a longer mx track the hrc would be great, but on a tight track, go w/something different.

Is anyone else having the same problem. I dont run to may wide open tracks. but am really looking towards the CRF cam at the moment

I'd love Chads 14:1 piston but this mite seem like a dum ?...will the starter wan crank that over...?? haha i dont have a lot of faith in the electric start but its all i could get at the time...

chad502ex
03-23-2008, 09:38 AM
Good question, but no need to worry.

When you install a higher compression piston, the decression mechanism is used to relieve cranking pressure.

The piston rings I use are Nitride, the very best rings use can get...

you can email or pm me for pricing,... the only problem right now is that I can't keep these pistons in stock... I plan on getting them in shortly, but it takes CP a couple of weeks to make each batch,...

usually takes me about a week to port and flow once the head is on bench..

for the 07, a web 943/921, porting, valves, a high compression piston, pipe and filter is an easy reliable 55-60hp...