'99 CR125 Bottom End

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5/10/2013 7:27 AM

I've got a '99 CR125 that blew the bottom end recently. This was a Wiseco replacement of the stock bottom end. The Wiseco lasted less than 10 hours, while the stock one lasted more than 10 years!

The connecting rod bearing is just completely shot & the rod has tons of play in all directions.

A couple of questions:
- I use Spectra premix, have forever. Recently I've heard grumblings that I shouldn't use Spectra, because this exact thing happens quite frequently. Could this have been the culprit? I can't imagine premix is the only issue here...

- I am hesitant to get another Wiseco replacement because of the poor life of this bottom end. Perhaps a Hot Rods kit? I live ~ 1 hr from Wiseco HQ, so I like the thought of supporting them. The parts failed and I haven't heard from them a week after emailing them, so I'm starting to get frustrated with them.



5/10/2013 9:06 AM

Wiseco has a problem with quality control, no big surprise since their stuff is made in China. Just my opinion, but they're junk. I came to own an 07 RM 450 with about an hour and a half on a complete rebuild on it, with a brand new Athena big bore kit, genuine Zook parts in the head, etc:. The crank locked up solid with that little time on it, smoked the new cylinder with it, as well as a couple of valves.
The guy who owned it called Wiseco and they basically said "Sucks to be you". He was so mad he parked the bike and went out and bought a brand new YZ250. I bought it from him a few months later, in the basket. He took an ass whippin' on that bike.
Does that sound like the kind of company you want to support? Just a thought here. If you still have the OEM crank, go get a Pro-X rebuild kit for $100 or so, and get the original rebuilt.
Hot Rods-Chinese. Your call.


5/10/2013 11:25 AM

We installed a Wiseco crank kit in my boy's YZ85 that had probably 15 hours on it when the connecting rod snapped in half and destroyed everything below the cylinder. There was no bearing failure whatsoever--the rod just snapped in half. That is nothing other than poor quality material.

I bought a blown CRF250R for $700 when the previous owner had 2 hours on a Hotrods crank kit and the rod snapped while he was in the air on a big jump--this destroyed the engine and nearly ended his moto career.

We now rebuild everything with OEM cranks, no exceptions for me. I know lots of people have had good results with aftermarket cranks, but I'm not taking the gamble anymore.


5/10/2013 11:39 AM

Spectro Oils is a very good oil (used at many years on the national circuit) Wiseco does have issues with QC, I would recommend going back to OEM crank.


5/12/2013 5:25 PM

Thanks for the input. I'm going to call a local shop to get some prices and see what they would recommend as well. Pretty scary stuff when the aftermarkets are worse than OEM!