Blown front sproket oil gasket

[Damoulianos Marios]

Hi all,

today on a short excursion, my mate in a state of panic forced me to pull over and stop. I stepped off the bike only to see the rear tyre and everything around it bathed in oil.

He thought my engine blew its guts off but I knew the problem was simpler albeit equally dangerous: The front sproket axle oil gasket was blown off because of the oil pressure and the oil ended falling on the exhaust (hence the blue smoke my mate noticed) and on the rear tyre.

This is the second time in three years that this happens to me and I think that this is TOO frequent, given the danger of such an occurence.

Does anyone know why this happens? Any other experience from forum members?

Both times it happened when the engine was revved high and hard.
My suspicions fall on the oil filte, which on the first time wasn't the one suzuki suggested (as I was told by the -then owner of the bike as I was test-riding it), and now... I really don't know what a genuine Suzuki oil filter should be writing on it.

If I don't find a satisfactory reasoning behind this (so I can avoid it) then by all means I'll consider changing bike. The first time I was doing 130MPH when it happened (and today "only" 100), so it's not an option continuing riding this bike. It just won't be fun anymore.

Oh, and my SV is a '99 one.

Thanks for any advice...

[petevtwin650]

If it were my bike, my first thought would be that the oil was over-filled, followed by checking the two (If I recollect correctly) oil breathers that go into the airbox to make sure they are not blocked.

The other reason could be cos the chain has been adjusted too tight and is pulling the sprocket drive out of true, this could cause the seal to fail I believe.

Certainly not a common fault.

[Well Oiled]

Frist thought would be breather pipes are blocked, causing build up of crankcase pressure. Is the engine old/worn? could be excessive 'blowby' past worn rings/bores, but that still shouldn't pressurise the case unless the breathers are blocked.

[Damoulianos Marios]

Frist thought would be breather pipes are blocked, causing build up of crankcase pressure.

That never really crossed my mind, thanks guys. The engine is not very old, around 35k miles only. I'll inspect the breathers and if they are condensed we've found the culprit...

[jamesobrady]

Dont suppose you've changed (or had changed) yer sprockets and chain recently?

I reckon its either, as said before too tight a chain, too loose a sprocket nut, or too tight a sprocket nut.

[Damoulianos Marios]

Dont suppose you've changed (or had changed) yer sprockets and chain recently?

I reckon its either, as said before too tight a chain, too loose a sprocket nut, or too tight a sprocket nut.

It's been many months since I changed the chain and sprockets although it may have slackened a bit lately. That's only a bit though...

[RingDing]

I agree with all the comments about what to check so far.

However, you might want to check the condition of the output shaft bearing whilst you're replacing the seal though. I had one fail on my GSX600F, which also caused a leak. It was quite noticeable when it failed as it was fairly catastrophic though! But a small amount of play in the shaft due to the bearing being on it's way out might cause a leak.

Not likely but seeing as how you're looking around there anyway its worth checking.