If it was mine I would use an air hammer without any locking device. That would rely on the inertia of the flywheel assembly to provide the resistance.
PD: Primary Drive undo ESA PD7
- Thread starter paw99
- Start date
They can be super tight sometimes, and difficult to undo if the bare engine is on the bench......... I use a 3/4" socket bar and modified socket with the taper machined off.........it is important to keep the socket level and square to the crank nut, or else you can easily slip and damage same. Heat the nut with a small blow lamp or an electric heat gun and the nut will come undone........it should be done up tight on reassembly around 70 to 80 Ft lb's would be a good figure to aim for........Good luck.
As an alternative to an air hammer, try an impact driver - it's like a cordless drill but delivers high torque in short bursts. They normally come with a 1/4 inch hex drive but one can get adaptors to take a 1/2 inch square drive socket. They have an additional advantage over a normal socket wrench which is that one can put all one's effort into keeping the socket pushed onto the nut when you pull the trigger. I used mine to undo the mainshaft nut on a Series A when the sprocket was slipping on its taper so I wasn't even able to hold the sprocket stationary. And the nut had been Loctited! Brilliant tool!
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Sorry folks, I forgot to thank you for the helpful suggestions. Many thanks, I may get to heating it, after first removing petrol tank and carbs (engine is still in bike).
You may have to replace the springs, After heat ?.
Cheers Bill.
Cheers Bill.
I now have access to an electric impact driver 1000 Nm (not mine) but the cost made me cringe for the occasional need a user would have. It would be something that back in the day if it had been available the local section would have bought for borrowing by members however those days of mutual help or widespread general use DIY motorcycle maintenance seem to have gone
Car wheel impact are cheap enough.
Battery.
I have a good air gun and good Commpressor from my Car Repair days.
Battery.
I have a good air gun and good Commpressor from my Car Repair days.
same as. stubborn nut ; off to local garage with an air wrench. on running machines I have them remove it then replace so I can ride home and remove at my leisure, no problem as long as you';re not twitched about flailing primary chain near your foot.
ps I always chuck the mechanic a 'drink' to keep him on the sweet side.
ps I always chuck the mechanic a 'drink' to keep him on the sweet side.
You want to try taking off Big End nuts, You need a 4 foot pole !.