depends how you look at it. XC will have better low end and mid range due to it's long stroke engine. The XC can be tuned to really perform but won't have the revability of the SX.
same chassis, main differnces are A arms, axle and seat height, and a minor diff in the rear shock location on the swing arm. A Arms and Axle will get it close to the SX.
XC engine is really good off theline and puts it's power down well and is easy to ride. SX really is a pro calibre engine that needs to have it nuts revved off and be very aggresive. If your in the C / B classes the XC is a good mount. Pro Am and up you'll appreciate the SX
SX is a different power delivery all togther, is it "better" well that depends...................
I was thinking that if i get a xc then i can get all the components for mx and switch between the stock stuff (XC) and the aftermarket (MX) and have a dual purpose machine. What do you think, is thta a good idea. Also what are some good aftermarket company's for engine performance parts.
I had a 06 trx450r with stg 2 hot cam and a 13.5 to 1 wiseco in it, i understand that from the sx to the xc engines that power is different on my 450r it was almost to abrupt maybe the xc would be what i need anyways because i like a smooth power delivery.
for smooth delivery the SX is your bike, the frames wont mount up, neither will the rear plastics. the xc is great, reliable, fast, nice shocks, but the SX is just the one step up from it, the higher price tag pays for better shocks and a better motor
ktm 8/06 cam
decent pipe, FMF megabomb header.
look at vortex cdi - bit more over rev would be useful.
still want more:
more compression, one of Trew's CP pistons.
Head work + TI valves from the dirtbike SX version of this engine.
Better rod - Baldwin Motorsports
yes, geniune part at a good price. This is the SX cam for that engine, nice improvment all round and better top end rev out. Really this is the cam these engines should have come with stock with IMHO...........
I personally think the RFS engine is a better engine all the way around. You can make it faster than the SX engine and it will last longer. The power delivery of the xc over the sx is better for all types of riding, the sx is better for mx only. Save the extra money for a arms and shock upgrades if that is what you want.