Feedback Needed Please ASAP

I will be contacting Honda tomorrow to check on the XR650R intake valves, they are 37mm and can almost bet they will go right in.....probably like the camshaft.

Did you receive my cam yet?

Not yet.

If it was me and I was getting a larger throttle body I would get +2mm intake & +1mm exhaust......Stock 700XX intake is smaller than XR650 intake but larger in capacity; 686cc vs 650cc.

This would not be going overboard; the 450R responds to +2mm in, +1mm ex very well. The intake charge velocity will still be very high even with the larger TB mainly because the stock 700XX is so strangled in stock form.........DS450 has 48mm TB & the new CRF450 has a 50mm TB!!!!

Linc

The exhaust valves are plenty big for even a large build so no need to up the size there.

That 37mm XR650R valve will work!
Stock 700XX valve measures:
Stem .259"
Length 4.029"
Groove for locks are right were it needs to be too.

Hell yea!!! That saves allot of trouble. They make a 37, 38 & 40mm Intake valve plus 32 & 33mm Exhaust valves for the XR650R. I'm not sure if the years are different but the package said 2000. I'll have some headed your way tomorrow.

Send em on! Honda shoulda put the 37s in there to begin with instead of the 36s out of the XR600.

VelociRaptor said:

That 37mm XR650R valve will work!
Stock 700XX valve measures:
Stem .259"
Length 4.029"
Groove for locks are right were it needs to be too.

Click to expand...

That info is awesome!!!:yay: It's good to have someone actually doing the leg work AND sharing what they know. Thanks

Thats what a great forum is made of! The XR650R cam will work too!

It's going to be really interesting to see what kind of numbers these modifications will get on a Dyno.

By the way Bo, nice work!

so if the XR650 cam will work, what will this do for the 700xx? With these bigger valves is that for boring out the intake exhausst ports?

We were mainly talking about aftermarket brands of cams, For example Hotcams makes a stage 1, 2 & 3 for the XR. Since they will bolt in we can get one, install and make more HP. I'll prolly use the stage II

The bigger valves are not necessary to have if you get your head ported but help make more power when combined with the cam and port work.

oh ok i see what your saying, im in awe of how honda makes stuff to be so universal. i can't wait to see it at the dyno. im looking forward to what i can do to my bike, just gotta get past the first maintaince and full break in period first.

ugh.. lol, I didn't even have 20hrs on it. Didn't have a chance to get the first maintenance. The cam was still mostly black also lol.

My Raptor had less time on it than that when I tore mine down lol.