Yamaha r6 engine problem

[Criggers]

Hey guys, sorry it's a completely different bike but I have a problem, I was riding home last night, heard a massive bang and bike juddered, turned around and found out that the bike has relieve itself of it's oil. I've striped her down and found this


I also noticed that the nut for the front sprocket is missing, theory is that the nut had come loose and wedged itself between the sprocket and cover causing it to crack, do you reckon it's a new engine jobby?
Cheers

[Criggers]

another photo

[jambo]

That's not great news.

Generally there's a tab washer behind the front sprocket nut to prevent it undoing even if it comes loose, this may not have been folded correctly or not been present.

Don't suppose you have the bit that got smacked off it?

Also can you confirm year of bike? I believe it's a 99-02 in which case, worryingly there are 2 other motors on ebay at the moment with identical damage.

Jambo.

[Criggers]

Its a 2000 and here's that bit

[Biker Biggles]

Did you stop the engine before the oil escaped or did it run with no oil for a bit?If the rest of the engine is ok it might be worth getting the case repaired

[Criggers]

Yeah stopped it before all of the oil ran out

[jambo]

OK,

The completely safe, solid, by-the-book answer is that you will need to either:
1) Strip the motor and replace that casing. Good news here is plenty of R6 motors have suffered gearbox or other mechanical failures, and you only need a good top casing, so the donor part shouldn't be too expensive. You will, however, need time and rather a lot of gaskets...
2) Swap the motor out for a good 2nd hand one. Most motors bought from a breakers will have something like a 28 day warranty, so you want to be in a position to swap the motor out very soon after purchase to give you time to find any issues. This can be expensive, but it's the fastest fix compared top option 1.

However, you've got the bits that came off, and there's a fair bit of surface area there to work with, as well as a bolt to hold it in place. Do the bits fit neatly back on to fill the hole?

I would talk to someone who knows about these things (such as a local engineering firm) to see if there is a possibility to attach this back in place using something like JB Weld, or actually welding the piece back in. With that bearing so close, you'll want to be very careful about anything getting in there that could damage it though. Practical Sportsbike magazine actually had a piece on repairing crank cases like this this month or the one before, albeit for non load-bearing parts which I'd say that is.

Definitely worth investigating repair options at this stage.

Jambo

Edit: Also, see if there's a tab washer to go behind the nut, and buy one if so

[Criggers]

So, had a word with the mrs' uncle, he said he will give it ago at using liquid metal on it, if not I'll just sell it for spares or repairs, I don't really need the hassle of fitting a new engine, seeing as I have 0 experience and don't really have the money for it

[jambo]

If it's not strong enough with chemical metal I would definitely want to contact a local engineering firm. If you sell it as is, you will loose a fair bit. Someone fixing this in a way they are happy with will potentially save you a fair bit of cash.

Jambo

[Sid Squid]

If you repair it by replacing the case, you'll need both - they're machined as a set. It might be fine with mismatched cases, but I wouldn't build an engine on the chance it would.