Author Topic: Torquing the primary shaft bolt, how to lock the transmission.  (Read 2991 times)

Offline Dolomite_

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Is there a way to lock the transmission with the tool to torque up the primary shaft bolt?

If there isn't an easy way to lock it before it goes back in the bike I'll just have torque it up when the cluck is on and I can lock it with the back brake.

Offline TrickyMicky

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Re: Torquing the primary shaft bolt, how to lock the transmission.
« Reply #1 on: June 06, 2024, 11:47:32 AM »
This may be a long shot, but, in similar circumstances I've jammed the teeth on gear wheels using the plastic spanner that's supplied with Flymo hover mowers. The plastic is quite tough, but not brittle, so will not damage the gear teeth.

Offline taysidedragon

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Re: Torquing the primary shaft bolt, how to lock the transmission.
« Reply #2 on: June 06, 2024, 11:49:04 AM »
From memory, you can put a clean rag between the exposed gears so when you torque the nut the rag stops things turning. Another way is to put a socket extension bar through the small ends on the conrods to stop the engine turning. HTH.
Gareth

1977 CB400F
1965 T100SS

Offline McCabe-Thiele (Ted)

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Re: Torquing the primary shaft bolt, how to lock the transmission.
« Reply #3 on: June 06, 2024, 12:07:23 PM »
I used the conrod method - I made sure I had a cushion between the block and the socket bar to prevent any chance of marking it.
Honda CB400NA Superdream (current money puddle)
Honda CB500 K1 (second money pit)
https://www.sohc.co.uk/index.php/topic,28541.0.html
Honda CB400 four super sport (first money pit)
Link to my full restoration http://www.sohc.co.uk/index.php/topic,23291.0.html
This is a neat 500 restoration in the USA.
http://forums.sohc4.net/index.php/topic,151576.msg1731556.html#msg1731556

Offline Dolomite_

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Re: Torquing the primary shaft bolt, how to lock the transmission.
« Reply #4 on: June 06, 2024, 01:56:11 PM »
I thought about putting something through the conrods but thought it might not be strong enough. I'll give it a go.

Thanks!

Edit: it worked perfectly
« Last Edit: June 06, 2024, 02:01:17 PM by Dolomite_ »

Offline taysidedragon

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Re: Torquing the primary shaft bolt, how to lock the transmission.
« Reply #5 on: June 06, 2024, 02:46:21 PM »
👍
Gareth

1977 CB400F
1965 T100SS