MK1 - Possible Rear Crank Gear Play

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allan.walker
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Re: MK1 - Possible Rear Crank Gear Play

Post by allan.walker »

I thought that I'd better add two new coupling gear keys to my Draganfly order. Guess what? Out of stock. That makes three items that I will need for my rebuild that are oos at Drags.
My fault for buying a 'niche' motorcycle, I suppose.
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Re: MK1 - Possible Rear Crank Gear Play

Post by Paul_Linden »

I don’t think a square four is particularly rare, for a classic bike. Draganfly carry a wide range of square four spares but there will always be something that is out of stock. Club spares might have them (contact name and number in Cheval), you might find something similar in an old school engineering shop (it’s 1/4 inch thick which is a ‘standard’ size) or you could try making one?
Square 4 mk1, Square 4 mk2, BSA C12.
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Re: MK1 - Possible Rear Crank Gear Play

Post by john.whiting »

Anyway,others have reported success using on the various Loctite anerobic adhesives .....so I would think this would be my first method of eliminating any looseness in the drive ......I do know someone brought me a boat propshaft and coupling to remove the cutoff shaft ......the combination of rust (stainless shaft/steel coupling) and Loctite meant the boat repairer had not been able to get them apart........The shaft finally came out of the coupling with 80 tons showing on the gauge of my old Rogers sprocket puller.
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Re: MK1 - Possible Rear Crank Gear Play

Post by john.whiting »

By the way,dont substitute home made keys for special application keys ......the soft key will shear and spin the gear on the shaft .....best case scenario scored shaft ...worst case gear welds itself to shaft .
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Re: MK1 - Possible Rear Crank Gear Play

Post by Paul_Linden »

If you make one yourself then obviously use the correct carbon steel. That should go without saying.
Square 4 mk1, Square 4 mk2, BSA C12.
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Re: MK1 - Possible Rear Crank Gear Play

Post by camstevens »

Hi
Please see the reply from Roger Gwynn on the first page of this thread.....it tells you the base key to buy....just need to trim then ends carefully.

I will be going on my first run today post reassembly....fingers crossed. Clunky noises gone when running on the stand, so promising

Cam
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Re: MK1 - Possible Rear Crank Gear Play

Post by allan.walker »

Good luck, Cam!
It looks like you may have solved it.

(btw, I couldn't see any reference to which suitable key to buy.)

Allan.
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Re: MK1 - Possible Rear Crank Gear Play

Post by camstevens »

Hi Aljan
1/4 × 7/8 807 BS 46 PART 1

I got that back off the website I bought it off, so should be correct

Cam
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Re: MK1 - Possible Rear Crank Gear Play

Post by allan.walker »

Thanks Cam. I've found a supplier on Ebay. A pack of 5 of the correct spec for £5.50 delivered.

Now, the big questions....did you manage to get out on the bike and have you cured the knock???

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Re: MK1 - Possible Rear Crank Gear Play

Post by camstevens »

Hi Allan
Yes......the knocking is gone, and I seem to have got a fuel issue sorted too. I'm pretty happy with it, a few noises from the primary side...perhaps that's the nature of the beast. Remenber, you'll need to trim the edges of the key back to fit within the gear. I'd still love to get the gearing up......always looking for another cog!

Cam
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