My new RGV has destroyed itself (pics)

[Yakman12]

Hey guys, after owning my rgv for less than 2 weeks, the engine has packed it in

i was driving along and lost all power then stopped, i couldn't get the bike to start again and heard a strange rattling from the engine everytime i turned it over

anyway i managed to get home and have removed the barrels on one of the cylinders and found the piston had a wee chunk taken out of it, also upon opening the barrels a strange piece of mangled metal also fell out

my question is what is this piece of metal? has me very worried as i cannot tell where it came from, i have some pictures attached to show you

http://i2.photobucket.com/albums/y1/...s/DSCF0073.jpg
http://i2.photobucket.com/albums/y1/...s/DSCF0071.jpg
http://i2.photobucket.com/albums/y1/...s/DSCF0068.jpg

also here is what the piston looks like:

http://i2.photobucket.com/albums/y1/...s/DSCF0074.jpg

[James Deuce]

Powervalve. Common problem on RGV's. Pin drops out, powervalve drops in, destroying barrel and piston in the process.

[onearmedbandit]

Being an RGV it's proberly the powervalve. Later models had the problem addressed from factory, some earlier versions had mod's performed on them to eliminate the prob. They wear out the retaining pin, allowing the powervalve to drop into the cylinder, where it gets to meet Mr Piston.

[Ixion]

Yep. What he said. Welcome to the wonderful world of two smokers. Good thing is you've got an early start on getting familiar with pulling down the top end. Practice makes perfect.

[Yakman12]

thats strange because the barrels appear un-marked, and the power valves seem to be in tact? i haven't stripped the barrel to check the valves fully yet, but the fins can still be seen and they move freely?

any ideas?

[Yakman12]

o.k i just pulled out the valves and they are fine

so its definately not them, the piece of metal kinda looks like a gear cog, but with really shallow flat teeth (best way i can describe it)

very strange, i'm thinking bottom end has let go?

[Ivan]

Not cool man looks like part of ya crank but the phot is pretty blurry,


Do these have a balance shaft in them like the RS125 Hondas?

Remember for it to be part ofya gearbox it has to have smashed the crankcase as a 2stroke is sealed crank eg seperate from the gear box so the only thing in a stroke which can fail

Piston drop piston circlip and you lose piston
Pover valve falling into cylinder
Spark plug melting hole in piston due to deting
Con rod saying bye bye and trying to get out into the world
big end bearing failure
Main bearings crapping out
Or crank breaking which I have never seen


Pretty gutted to hear this

but also keen to see what it is

[The Pastor]

sounds like what happend to magua, i think it was a bearing or somthing?

[Yakman12]

o.k you guys are gonna love this

its the big end pin that has let go and is now a smashed up hunk of metal

you can see the pins here on this good crank

http://www.rgv250.co.uk/forums/uploa...1110219160.jpg

grooves are the same as my piece of metal

i've never heard of anything like this before, anyone know what would have caused this? maybe oil pump failure?

[Ixion]

Aye. Seized big end, and broken crankpin. It's a two stroke, it happens.

Causes, too many revs, for too many hours, maybe cheap oil in the past.It's a two stroke, goes with the territory. Lucky Mr Conrod did step out for a breath of air. Rod(s) will be stuffed of course.

New engine time.

[Yakman12]

yep new engine alright, good thing i happen to have a spare bottom end

the thing that worries me is on closer inspection one of the barrels has some small grooves in it, just how bad does it have to be before i will need a new barrel?

[Mr. Peanut]

Wow, the guy who sold it to you had good timing!

How much you pay for it?

[Yakman12]

$2000

supposedly top end rebuild, plus the bottom end was meant to have been checked out, it had high km's (50000) so its no wonder the crank gave up the ghost

the high km's is why i went and bought a spare low km bottom end, i was planning on swapping it over, i just didn't expect the current one to destroy itself before i had the chance haha

it had a fresh warrent and rego and is in fairly decent condition, so i'm guessing $2000 is not too bad really, i'm just pissed off my barrel may be damaged too much, dam costly those things