xt cranks
 

I am looking to upgrade my crankset on my rm 2003 slayer. I was thinking of going to xt crankset any suggestions on which one to go to the 2003 or the 2004. What is the benifit in the different size 170 mm to 180 mm. Or any is there any other suggestions for crankset for xc and dh use. thanks out

Why bother, the cranks on the 2003 Slayer are far superior than xt cranks.

the bottom bracket that came with my slayer only lasted about 250 miles maybe does anyone have any suggestions one what crank to go to my bike came with race face isis

Sounds like the tech that set-up the bike did a poor job. Even the cheapest BB should last longer than 250 miles. If that is all you got then you should be able to get it replaced under warranty.

That said, I use an '03 XT crankset and think it is just fine. Have scarred my shins many times on them and hasn't hurt them at all. They are as good as new and I now wear shin armor.

As far as length goes, 170mm is the crankarm length and is generally for us smaller of leg folks (31" inseam here). There are several threads here that will tell you about getting the correct crankarm length. Do a search on same and you will come up with a dozen and more info than you ever wanted to know.

thanks for the input that is what i thought they did warranty the part with the same one and I did not want it to happen again.

i have a set of 180mm holzfeller that i upgraded from a set of 170mm hussefelt - they use isis spline. both cranks are great. i just needed longer crank arms - and i'm a short rider (5'5") just like the feel of the longer arms. if i'm not mistaken, you get more leverage

Long cranks enable you to turn larger gears at a slower cadence. With small cranks, you can turn a smaller gear, faster. In both cases, you are outputting the same amount of power and going the same speed. Cranks do not increase your power.
Long and short are relative terms. The "normal" size depends on your leg length. You also need a crank which will not interfere with the front wheels, and which gives sufficient cornering clearance.
For ave male (5'10), a 170-175 is about right for off-road riding.