blown up engine1200cc

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coolade

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i paid 400 bucks for a 2000 vmax , bike was nice but the crank shaft had blown out threw the front of the engine i was wondering what would make it do that,
 
I would have thought the most likely cause would be something overheating due to lack of coolant or lubrication failure.
Lots of reasons what may cause that and only careful examination of what is left may give you a clues as to the cause.

One other possibility would be a mechanical failure due to over revving.
I'd discount any manufacturing faults as it survived twenty years or so before going bang.
 
I'm thinking a rev limiter might have prevented it. Sounds like someone might have missed a shift and pegged the tach. The crank in pieces?
Can you post a couple of pics?
 
Finally a possible sale for the guy with the Gen II crate engines!
 
Will the gen 2 motor work on the gen1?
Nah, I was just kidding.

A roller waiting for a new engine is probably worth about a grand, assuming everything else is in good shape. A replacement engine is gonna be about the same.

I wouldn't pay a grand for a bike needing a new engine, unless it had extras and it was in really-nice overall condition.
 
i got a lot of photos i just took today i will figur out how to up load them here lots of damage, 2 dead pistons , crankshaft ,1 con rod , 2 cracked barrels ,upper and lower case ,water pump
 
im just going to buy the upper and lower cases and swap my internals and replace damaged parts, easy fix for me, ive got a 94 vmax with 4800 miles on it , i got this one with the bad motor cause it had new mitchelin commander tires, front and rear so i could put them on my 94max, but the condition of the 2000 max is a++, the paint work is excelent the carbon fiber mud gaurds and tank look brand new so for that reason i going to rebuild the motor and have two bikes
 
with the amount of force that blew that engine apart, can you be sure it hasn't caused bending or mis-alignment of the 'undamaged' areas
If you can piece that together, I'm sure that you will use the specs measurements for all the tolerances on the parts as it goes back together, to prevent the thing grenading from out-of-spec clearances and measurements. You might as well have the gearset undercut to forestall 2nd gear issues down the road. It shifts so-much better when that's part of a rebuild.
 
The cases are line bored. I have seen (and done) a lower case swap but would not suggest it. Just get a good lower reciprocating assembly or complete engine (I have various options on hand). Spun bearing motors are generally not worth rebuilding since it also damages the case on the thrust surface that most machine shops aren't set up to repair.
 
I'd be interested to see how a repair can be carried out on the thrust "bearing". Yes you can machine the casing true, and get a good crankshaft, but your clearances would be too wide unless a bronze thrust washer is fitted - but what holds it in? Maybe a ring?
 
We have repaired spun bearing blocks but it's cheaper to get a good one with bad trans and swap those parts out. I have a few like that if needed. Here's a pic of the repaired area with added oiling. Edit, I thought I had a repaired pic. We machined down the surface where the new bearing would restore the original spacing. Then countersunk and lock tighted flush head fasteners into it to hold the new bearing in place.
 
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