TC cam (XC grind) or XR 400 cam??

[Adams44]

I currently have a TC cam (XC grind). I raced on it all year and did several modifications when I built the motor...so doing all the mods together I am not sure what the cam did. I have good all around power with probably more mid range.

I am building a motor for a friend and would like some input on deciding which one to get. We can't afford to hardface the rockers, so that leaves us with the softer honda cams and TC's (XC and MX) are reground honda cams, I believe. Also the XR is much cheaper ($140) (TC $175 plus a core cam).

What increases can we expect for the XR 400 cam?

Is it an all around increase by lift and duration or does it simply move the power band to a certain RPM range by changing duration?

Does anyone have the lift and duration specs on these cams?

Thanks for clearing up the mud.

I use the XRcam and think it will do the job for your buddy just fine,,I didn't feel any loss in the bottom, mid, or top,,just alot more power all over along with the new piston..

Oh and look somewere in the motor forum theres a list of those duration specs you were lookin for..it lists about 5 different cams,,good info.

[86atc250r]

No cam will give you an all around increase unless there is a design problem with the original.

Camshafts are a compromise, if they weren't, there wouldn't be so many available, there would just be one that did everything well.

That said, I'm assuming that TC's XC cam is probably more aggressive than the XR cam, but I haven't seen any actual specifications.

Personally I run the XR and love it. I can complete a 2 hour XC race on all but the fastest, most open courses without even hitting reserve on the stock tank - I have never had to refuel during a race.

It raises the power into the midrange a little, but if you combine it with a higher compression piston and a carb, you'll end up with more power everywhere.

That's what is allowing me to get better fuel economy than stock, even though I'm running an FCR 39mm, XR cam, 10.8:1 JE 416, Sparks X4, etc... It has so much bottom and mid that I don't have to run it in the upper RPM ranges to get power on most of the course, yet it still has enough top end to run with (and in most cases, outrun) the bigger bikes in the straights (Raptor, 440's, Rs, etc..) - the best of all worlds for XC.

The XR cam is about $120 from servicehonda.com -- if I remember correctly both lift and duration are increased somewhat and the lobe centers are different.