Gearbox shell failure

Respect to Ludwig for taking the high road on that one.

@Time Warp:
reading your post # 18 again, I first of all want to thank you for your suggestion of a 'homemade two pin bar' to hold the sprocket. I would never have thought of that myself.
But std sprockets don't have holes, so I had to fall back on my old method of holding the sprocket with a socket :



This is on my N15. Internals are Commando, but the gearbox shell is still the original after +/- 250 000 km.
They are different from a Commando shell, so I would hate to see it cracked.
To hold the sprocket I could have used the method suggested by most manuals: push hard on the brake pedal, But then:
1. I need a chain installed.
2. All that torque ( your 70 ft/lbs ..) would be transferred to the brake shoe pivot pins and brake plate. A known weak point.
They usually survive it well, but I still prefer to put my money on the swingarm spindle.
3. But most of all, the stress on the gearbox and casing would be exactly the same
('short arm fulcrum' and all that..) either using a socket or the chain to hold the sprocket.
Going by your post #18, I can only conclude you figured out a better way to tighten the nut.

Would you please care to share that knowledge with us?

I had a nipple pull through on a brake pedal doing that. A commercial cable not home made.

I guess that was a good thing because it taught me not to trust commercial cables.

Since then I have also seen three of the tiny nipples pull off choke and throttle cables. Name brand. Two on my Commando and one on a Velo. Amal carbs..

(Not official data)

(Source: MRT Castings)

I use the same principle to tighten cam sprockets, engine sprockets etc... aluminium flats wedged diagonally between the sprocket teeth, there's a pic of this somewhere on here but I'm too lazy to dig it up.

For that gearbox sprocket the small socket is clever, I recall cutting down an old length of chain and clamping it with vise grips the last time I swapped one out... but it was awkward bearing the visegrips against my foot while tightening, I'll probably try this next time

acadian said:

I use the same principle to tighten cam sprockets, engine sprockets etc... aluminium flats wedged diagonally between the sprocket teeth, there's a pic of this somewhere on here but I'm too lazy to dig it up.

Click to expand...

I've done it for 45 years, motos, cars, trucks, CNC machinery.