Boxerworks.com

I had a spill last Friday, Travelling down a 2 lane road(dual carrageway) in wet conditions, as the road merged into 1 lane I dabbed the front brake and Whoosh - I was off - (spilt diesel!). As I rolled over and over down the road I saw the bike sliding down the road in the opposite lane. When I stopped and got up I could n't see the bike - it was standing upright on its front wheel in the hedge.
When the recovery truck picked it up they layed the bike down on some tyres and I could see that the rear wheel was out of line - moved to the right.
On getting the bike home and having a closer look I could see that the r/h rocker box had been torn off bending over the exhaust rocker posts but worst of all the gear box casing has cracked - the worst side being the l/h side.
I'm presuming then as the l/h side rockerbox is un-marked that the bike whent down on the right and then after sliding hit the curbstone and catapulted the bike over the grass verge up into the bushes.
What I want to know is what sort of impact would of broken the gearbox shell?

http://i120.photobucket.com/albums/o187 ... /Head1.jpg

http://i120.photobucket.com/albums/o187 ... /Head2.jpg

You're typing, so that's a good sign Nourish. That's a King Hit.
How are you? Funny how one has time to observe the trajectory of ones bike (and approve or disapprove) whilst one is flying through the air.
I think your bike qualifies for the 'catastrophic damage' class.

damn shame, a good looking machine too.

but good thing you walked away.

I walked away from this without braking my skin - no real bruises and nothing my chiropracor can't fix - I was really lucky - got to find a new Jacket and Helmet though.

This wasn't my cafe racer thingy but my '89 Mono

http://i120.photobucket.com/albums/o187 ... 7_3774.jpg

The damage was caused as you suspect, by the high side part of it. I am just glad that you had parted ways when the high side occurred.

I predict that you will find that the frame is badly bent. It could be bent in the front end, but if the front wheel and engine front cover is OK, then it may only be bent in the rear. It is the box section at the battery that would get my attention first. Of course you can very quickly check for a bent gusset at the head stock and remove the tank to lay a straight edge on the backbone.

I also suspect that you have far more transmission damage that just a cracked case. Remove the front clamp on the the rubber boot, peel it back for inspection. Then carefully inspect the flange that the boot clamps onto. It is common for that flange to be cracked and it is usually on the inside where it is hard to see. I have never seen that flange get cracked without also bending the frame. As the frame is going through the trauma of bending, the drive shaft is flexed to one side so much that the output flange is shoved over and cracks the flange. In the worst case, we found a flange where 1/3 of it was broken out completely.

In a worst case, and you may have that, the output shaft can actually break. That is easy to see/test, as grabbing the U-joint and shaking it will reveal that it is loose. You might need to use a bar and pry it a bit to see that.

With the bike straight up, check for wheel alignment. I think that it will be so bad that you can see it by eye sighting it from the front. You can always check it quite accurately with a string line test. Go to http://w6rec.com/duane/bmw/frame/

Another simple test is to remove the rear axle. Get the wheel out and attempt to put the axle back in place. Does it go in with finger pressure as it used to? Probably not.

I would expect to find that the damage is to the box section at the battery.

Get an estimate, but only after you have done a lot of your own checking. Maybe your local shop doesn't get enough of these to be able to do it. If they have a frame jig, that is the gold standard. I predict that it will be a total loss. That doesn't mean that you can't fix it yourself if you like mechanical work and have the time to source parts etc.

That was almost all bad news. The only news that counts at all is that your frame isn't bent.

Bummer about the bike, but so glad you are relatively OK!

Thanks all and Duane for the info.
I imagined that the frame would be bent and that it would be cheaper to buy another used one than get this one straightened.
But I quite fancy adding all the bracketry and running gear from this mono frame to a pre 75 one and then it would be Tax exempt here in the UK (road fund licence) - that would save me £78 a year!

What, you don't want to pay your "fair share" to help those with less? A good citizen like you should be more than happy to assist those not so lucky and help the government spend more and more...... and more.

Do you have a scratch on your helmet? I bet that you hit your head, and just a little tap might do it.

I recently sold a couple of frames that had titles and only got around $100 to $150 for them. Then your frame and engine number won't match up. Just think how you would feel riding down the road knowing of this mismatch.

Yes I have scratched my lid, I've dug out my old one for now.
There is a certain amount of satisfaction of riding around knowing that the bike is tax free-unlike anything else in life!!
Frames - tax exempt frames are a little more than that over here, In fact I looked at one on the US Ebay and it would be much cheaper to pay the postage to import it but I'd have to get a new UK 'Title' for it and as the engine and other major parts are from the wrong period would mean it wouldn't be tax exempt - I have to buy one with a UK 'Title'.

As you take it apart, please let me know what you find. I wonder just how much of what I remember is still accurate.