Blown Rocker gaskets.....

[mart3442]

Further to my backfire post (which may or not be relevant.....):

Out for a little blast last week, I stopped at a services for a "comfort break" as our American chums would say.
When I fired the bike up there was a popping sound, followed by a big cloud of blue smoke from under the fuel tank. I Switched the engine off and ran away sharpish! Realising that the bike wasn't actually on fire. I came back and had a closer look. I discovered that the rocker (valve) gasket on the rear cylinder had blown out its "Half moons" and oil was pumping out fast. Back home with both covers off for inspection, the front gasket had blown one half moon and was also showing signs of not having been sealed correctly.
All the exposed engine internals were fine, as were the gaskets. All surfaces were cleaned and the gaskets reseated with a very decent gasket sealant. Having given the engine a thorough clean and degrease, I changed the filter and what was left of the oil and tentativley fired the bike up.
Absolutely fine, no leaks, noises or anything untoward. I know this has happened to other VTR owners but is it just one of those things or are there specific causes?

Cheers.

[Ckennedy]

I am sure I will be corrected if I am wrong but it is possibly just one of them things. If they have been changed in the past for poor grade gaskets, just set wrong and even just time a gasket can go at any point. It does not have to have a cause. I have a truck at work at the moment with a blown head gasket. No previous issues, well maintained and then all of a sudden the header tank is compressing just after start up. Just one of those things. I have not had it happen to me yet, fingers crossed it won't. I do however have a clutch that sounds like a Ducati

[mart3442]

Thanks a lot, thats reassured me a bit. I had a look on the Superhawk forum and theres all sorts of theories regarding "Explosions in the crank"....The guy this happened to actually rode his VTR home! If it was anything like my blow out, there was a bout half a litre of oil left in the engine.......
Fingers crossed its just a one off. I also have a clutch that sounds like a Ducati, mind you, it is on my 750SS.

[VTRDark]

It's not a common problem with these bike but like CK said a gasket can go at any time from wear and tear. Or maybe the previous owner had the cover off and did not re-seat it properly. A good dollop of gasket seal always helps to keep things in place, especially around the U shape where the plug is and towards the rear where it can fall out when tightening the cover back down. Glad you got it sorted anyway.

(:-})

[agentpineapple]

with first hand experience me and carl know how tricky they are to seat properly, maybe the previous owner had bodged it, at least now you've done it you have peace of mind, keep an eye on it for a bit, just to make sure there isn't any oil leaks.....

[mart3442]

Thanks chaps., much appreciated!

[tony.mon]

I don't think it should have happened, as there's no pressure inside the engine to cause it to suddenly pop out.
You'd need to have trapped the cam cover breather, check and make sure they're both unkinked.

However it's quite easy to have one out of alignment when reinstalling the cam covers, if they've been off recently?

No real damage is likely to ensue, just an oily boot, normally!

[mart3442]

I've only owned the bike a short while, this is the first work I've done on it. Yeah, I did get an oily boot. I got my mate who can rebuild most engines with his eyes closed to reseat and seal the gaskets as I'd not done this myself. The bikes been up to running temp a couple of times now and has Been out for a short run. I feel pretty confident that it will be ok.....He says.

[Rob]

I don't think it should have happened, as there's no pressure inside the engine to cause it to suddenly pop out.
You'd need to have trapped the cam cover breather, check and make sure they're both unkinked.

However it's quite easy to have one out of alignment when reinstalling the cam covers, if they've been off recently?

No real damage is likely to ensue, just an oily boot, normally!

I would check, or get someone else to check, what tony.mon suggested no matter how the bike feels now. He is very knowledgeable on these bikes.

[mart3442]

Yeah, I'm keeping a close eye on things....