850 blowing motors

[catrutt]

I would like to know why there are so many 850's for sale that have new motors with only 3000 km.I thought they were made to run 10,000 km. The old 800 would do 5000k easy.

 

[FastFarmer]

This can’t be the start of anything happy! Good thing it’s gonna be +20 tomorrow!!!

 

[Dmf]

I would think the ones that are blowing are mostly due to over revs when the belt goes. Hard load to nothing

 

[Adam31]

I would think the ones that are blowing are mostly due to over revs when the belt goes. Hard load to nothing

What belts going, haven't heard anything about that yet.

 

[powpowpowpow]

5000 hard kms and all is good.

 

[Caper11]

Blowing belts, over revving the engine, and its a new engine, there is bound to be some failures.

 

[skegpro]

Crank bearings seem to be the main culprit.

 

[zenk]

most of the new engine sleds your seeing on kijiji are rental sleds, and personal sleds from dealers like riders.
last year riders had 4 850s for sale all with new engines.

 

[Teth-Air]

most of the new engine sleds your seeing on kijiji are rental sleds, and personal sleds from dealers like riders.
last year riders had 4 850s for sale all with new engines.

This must be the 2012 Polaris thread?

 

[JungleJim]

Fake news...

 

[Teth-Air]

Fake news...

Jim, to be fair your belts have done fairly well so maybe your motor never got the extreme over-rev condition that results when blowing at full load. Johnny did see a bunch go down in Revy last season and maybe from the same bunch that was popping belts every ride? Blowing belts also can cause strings behind the clutch to take out the crank seal and also twist the crank to make the "run-out" come out of spec.

 

[JMCX]

All these modern engines have rev limiters do they not? No doubt some of these belt failures can be violent though. The Doo 850 crank is two-piece. Supposed to be tougher. And by all reports it is very well oiled.

 

[catrutt]

Is the extra heat from the clutch cooking the bearing like the old days?

 

[skegpro]

most of the new engine sleds your seeing on kijiji are rental sleds, and personal sleds from dealers like riders.
last year riders had 4 850s for sale all with new engines.

Fernie had one go and doo couldn't even tell the cause of the failure. Looked like a bomb went off........

 

[tex78]

Jim, to be fair your belts have done fairly well so maybe your motor never got the extreme over-rev condition that results when blowing at full load. Johnny did see a bunch go down in Revy last season and maybe from the same bunch that was popping belts every ride? Blowing belts also can cause strings behind the clutch to take out the crank seal and also twist the crank to make the "run-out" come out of spec.

He wasn't the only one either, I seen way too many also

 

[Teth-Air]

All these modern engines have rev limiters do they not? No doubt some of these belt failures can be violent though. The Doo 850 crank is two-piece. Supposed to be tougher. And by all reports it is very well oiled.

Rev limiters only shut the motor off above the max rev point, it does not stop the motor from freewheeling way past that point when the load is lost.

 

[skegpro]

.....

 

[NoBrakes!]

that's awesome! where dat?

 

[kanedog]

Belts dont grow on trees you know!

 

[niner]

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