800R PowerTek - Running on no oil - blown engine?

[sherlock29]

I had an 04 800HO that i went thru 3 motors in... all top end.. but i replaced the 2 outer bearings, and if i remeber correctly the 2 outers are open,and the centre is sealed. you can score the cylinders/pistons pretty bad and they will keep on running... but these things dont like hot lunches... One of the times i blew mine was because it heated up, and the anti rotation pin(piston ring groove) actually got pushed in farther and the ring spun and opened up on the exhaust port, breaking the piston/ring, and taking a chunk out of cylinder.... the third motor was the last straw.... and now i have a fleet of yamaha's.... 21000 combined miles on the apex's without a hickup.

 

[rxrider]

I have changed the thread name to clarify what the thread is all about.

rxrider
TY Management Team

 

[blueironranger]

Are not doo crank bearings sealed?
If this is the case if you have good compression still i would run it to see what happens. Running it till the light comes on is no big deal, its continuing to run it once on that will do serious damage.

Yep, one of the down falls of those motors might have actually saved him this time!

 

[blue er]

you will have to measure crankshaft thrust and endplay to be sure with a dial guage, also if your over 5000 miles better off to get the crank done anyway it'll be do soon other than that you got lucky from the sounds of it

 

[05RXW]

I have done several cranks in these motors, and there was a change in 06, they went to sealed outer brgs, but it had open inner brgs, closest to the water/oil pump drive. so they had 4 crank seal, two outer and two inner. i have repaired my share of blown motors, an with what you have described, the crank may still have life, but like blue er said, if it got a lot of miles, then it better off getting rebuilt. an if you scored a the pistons at all, with plated cylinders, there is a good chance you hurt the coating and they should be replated. That my Professional opinion.