What crank to use cr85

[Nick's #1 Fan]

I am rebuilding a 03 cr85 and i am wondering what crank and piston i should use. Up till now I have used OEM stuff but we are racing some off-road races and I need to see if there is something that may be a little more durable.

Another question:
what is the life expectancy of a bottom end for an 03 cr85. I rebuilt this motor a little over a year ago and we raced it in the last 18 months a total of 9 times with some practicing inbetween.

It seems weird that I would have to rebuild the bottom end but I am still getting comfortable with these motors.

As always thanks for the help!

 

[IndyMX]

I'd say that you probably went over a bit, if you were going by the service manuals recommended service interval.

Have you looked at Hotrods?

Motosport.com has an entire engine kit for the 85's thats around 300 bucks.

 

[SHSPVR]

A good complete motor rebuild cost way more then 300 and overhual like what he ask is a cheap way to go with out rebore but you better have your cylinder check out.
Nick's #1 Fan note that the CR80/85 have Nikasil Plating unless you had a cast iron cylinder sleeved installed any way I got mine done at lukesracing.
Hot Rods Crankshaft Assembly, Crankshaft Bearings set, K&S Complete engine seal kits and Cometic Complete gasket set
As for you piston you need find out what size it is and get a Wiseco piston Kits
Now as for the Crankshaft both CR80/85 from 1986/2003 share the same crankshaft.

 

[IndyMX]

Yeah, have you looked at the kit from Motosport? It's not cheap junk.

There's no reason to spend more than $300 bucks on parts for that engine. Having the cylinder worked on is a different story, however, since the OP only mentioned that he needed to rebuild the bottom end, and from the tone of his message, seems he at least knows enough to have done it in the past, I'd say that's not required here.. Unless his teardown reveals something more.

Anyhow, like I said up there ^^ Motosport.com has a complete kit that's well worth checking out.