07 800r mag pistion low compresion

tex78

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ok was out yesterday and was good till it sounded like it loaded a plug...

go her home and has 12 pto and 90 mag.... have mcb 2 ring pistions in there...has 1100 miles on the pistions

got the borascope out and there is dents on the top of the pistion.. i'd say the top ring locating pin came out.....

i have heard rktec pistions doing this but now mabe the mcb's are too...

if it was pinging to loosen the pin likei have seen said before shouldn't the knock senor keep it from doing this...
 

LBZ

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Well that's lame.

I didn't think the '07 R knock sensors and computer were as effective as the ones that came in the R's in the later years it but I could be wrong.
 

tex78

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yep road a m8 this weekend....... it is close to riding the rev... but don't pull like it or have the snap.... the m1000 i also rode a bit was way snaper
 

MoFoREVxp154

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Chance are the inner crank bearings came apart and went through the top end and dinged it up.
 

tex78

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huh..... the engine has 1300 miles on a doo updated 800r [ under warranty ] there is nothing wrong with the raves [ 2011 e tech ones ]

rings are still there [ at least the exhaust side that i can see ] ....

how would the crank bearings get up there....and it runs with no noises....

if ya rev her up to like 3500 its smooth and sounds normal.....
 

imdoo'n

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tell them what you really think there tex. with crank bearings going throgh the engin, should have a shheeet load more damage in my opinion. i'm thinking you guys have not been there. i'm thinking jeff has a handle on it, or he may be getting a new kitty, likes stroking those furry kritters, :beer:
 

LBZ

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tell them what you really think there tex. with crank bearings going throgh the engin, should have a shheeet load more damage in my opinion. i'm thinking you guys have not been there. i'm thinking jeff has a handle on it, or he may be getting a new kitty, likes stroking those furry kritters, :beer:

:beer:
 

jackinthebox

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inner crank bearing's dont cause that much damage(sometimes)....yes i've been there done that.....I still was able to reuse my head took some emery clothe to the small dings,and the piston wasn't that bad(it was f'd but to look @ it didn't seem too chipped up) ,But cylinder was messed and once I got the cases split there were no bearings left in the INNER bearing and after a magnaflux of crank there also was fracture.So yeah been there.My rave valves were mint also.

But hey you could still have other issue's.And if Jeff has a handle on it then who cares what anyone thinks or there opinion...Dont ask then.
 
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