Cush drive bearing nut locking washer. Not sure of how this one works. It locks into the splne and wobbles until the nut is firmly tightened against it? Is that the scenario?

email (option): unpob@yahoo.com

Hi Henri..Yep...Fiddly things to fit as they tend to fall out of position as the nut is tightened. I never use them myself.
I just do up the nut all the way until it bottoms out on the sprocket carrier and then knock it up tight with an aluminium drift.
If you feel some form of locking is absolutely necessary then you can use either the lock washer or an old crankpin nut as a locknut, fitted with the tapered side facing the engine....Ian

Okay, never found them about, and now know why. Thanks.

email (option): unpob@yahoo.com

It happened twice to me before I discovered what it really was, that rattling sound when trying to kick-start: a loose crankshaft nut.
When riding, it will tighten itself, but when starting or braking with the engine, it has a tendency to unscrew.
That locking washer is indeed very difficult to apply, so I made a locknut from a worn nut (there is still some space between the end of the crankshaft and the face of the nut), and secure it using a pin spanner and Loctite.





And I use a suitable C-spanner on the nut, no hammer and drift

email (option): viaconsu # planet dot nl

Looks good Hans, another project for Robb.

email (option): unpob@yahoo.com

Or you could buy one of these which allow you to tighten & undo with a rattle gun,no more trouble or hammering with a punch/drift.The only downside is I had to machine the shoulder down at the rear on my lathe as if left it hits the outer chaincase. Dave...

I would really love to get my hands on one of the nuts that fits into the recess of the crankshaft nut (not the SRM one). Anyone feel like making a run of parts? I'm sure I'm not the only one.

Kevin

I want to know where on earth you buy a pin spanner like that?

email (option): brucekirby@telkomsa.net

I got one from ebay, they're very cheap.

http://www.ebay.co.uk/itm/Laser-Adjustable-Pin-Wrench-/200873659732?pt=UK_Hand_Tools_Equipment&hash=item2ec500cd54

email (option): horror@blueyonder.co.uk

One or two more questions, if you can stand it.

How do you immobilize the crank when you're torquing the nut? Wrap a bit of chain on the front sprocket? 65 ft lbs is the right value, yes?

Kevin

Put the bike in gear with the rear brake applied, this should hold it for you, but it would probably be easier if there was someone else to do this for you while you tighten it up or alternatively you could use a piece of aluminium bar cut so that it is snug and place it diagonally across the engine and clutch sprocket

email (option): davmax@ntlworld.com

That is a great idea about the aluminum bar. Thanks, David!

Kevin

I hate that cush nut thing and the locking washer.
Mine came loose and was gouging on the inner primary.
i think this caused probems inside the engine.

my drive side crank spacer was worn down and the crankpin nut had scraped the crankcase.

I totally agree. That's why I REALLY like the idea of Hans' solution shown in his photo. I'd love to find someone to make one of these!

Hans WDM20 58764

It happened twice to me before I discovered what it really was, that rattling sound when trying to kick-start: a loose crankshaft nut.
When riding, it will tighten itself, but when starting or braking with the engine, it has a tendency to unscrew.
That locking washer is indeed very difficult to apply, so I made a locknut from a worn nut (there is still some space between the end of the crankshaft and the face of the nut), and secure it using a pin spanner and Loctite.

Hi Kevin,i have the taps,so as i am pretty busy at the moment,i will make some of these in the next few days.i will keep you posted.Anyone else want one while im doing?
cheers Rick

email (option): richardholt@rocketmail.com

Hi Rick,
Yes please I would like one. If you could email me when ready with price and post to Perth , Western Australia . (Is paypal ok?)

Cheers,
Mike

email (option): jamik@westnet.com.au

Dave, you are a bloody genius!!!

Just tried your aluminium rod method of blocking the crank and it's perfect!
When I think of all the blood (literally) sweat and tears (oh yes, there were a few! ) I've shed in the past when this 10p solution was lurking in the scrap box all along!!





I definitely owe you a beer!

Cheers
Pete

email (option): petercomley@web.de

That is a pretty nice solution. I assume you don't even need to have the gearbox in gear, right?

Kevin

I remember about eight years ago, Henk had a photo showing how to jam a flat head screw driver in the chain.

email (option): unpob@yahoo.com

I was able to successfully use this technique today.





It's a really brilliant method. Thanks, Dave!

email (option): ahum@quicknet.nl