Crank Bearing Out on MM700

[MNpowderfiend]

I was riding with some buddies yesterday here in MN with our 12" of new snow. Good times, good ride. Near the end of the ride the motor stopped. No good. I popped the hood and saw pieces of a bearing laying under my primary clutch. It was obvious the motor bearing right behind the primary went out. The motor still runs, I pulled it over again, shakes like crazy.

So this morning I added up a parts cost for new bearings throughout the motor, gaskets, rings, seals, etc. I'm upwards of $1200 just for stock parts, (best case scenario parts - reuse cranks). I like the sled, bought it brand new in 2000. I've got about 6000 miles on it and have had it 10 years, so I've gotten good service from it. I've always maintained it, fogged the cylinders, stabil, etc.

I maintain my own stuff, do most mechanic work, but I'm not a motor guy. I would have to bring this in. So $75/hr shop x 16 hours?? = $1200?? for building it. So I'm into it for $2400 on a 10 year old sled as a minimum.

So, I'm thinking about parting this one out and buy another sled. I've got a 151" on it, bar risers, Bender Pipes, etc. Maybe get $1200 back in parts??

Essentially $3600 towards a newer sled.

My question, are my figures in the ballpark?

Thanks, Eric

 

[attak06]

mm77 crank

give this guy a call, his name is josh. he is in the cambridge mn area. he has been doing cranks for years. check him for a price.
1-612-308-4853. he has done a few yamaha cranks and tons of polaris cranks. here is hie new web site http://www.jwsnoweld.com/ i talked to him today, he is doing a sx/mm 700 crank right now. he should have a good idea of the cost. he is quite a bit cheaper than having a machine shop do the press work.

 

[Lt Rascal]

I had a friends '97 that lost that bearing I rebuilt it for him. I cost around $1200 in parts but that was with a new crank. $700 for the crank but by the time you buy bearings and a shop to do the press work it was worth it. But then when my '97 lost the same bearing I lokked for a complete motor and found a 2000 motor for $1000. Then parted my old motor out. To be honest I made money in the end. Sold the case, pistons, cylinders, head, pull rope assembly, and stator.

 

[TRIPLESWILLNEVERDIE!]

It will all depend on the condition of the crank. If it only needs the PTO outer bearing replaced then thats not an expensive fix. I would be willing to bet it will need more than that though. You can get new Yami cranks pretty reasonable through some of the online Yamaha parts retailers. check around. You mentioned that you do your own maintenance and that throws up a red flag as to PTO bearing failure. Have you ever rebuilt your clutch? That is likely the cause of your problem. If you go to the trouble of repairing your engine be sure to have a pro rebuild the primary clutch. That is very important.