Trouble engaging 1st gear

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Hello all, I have a 1973 850 roadster with a gearbox annoyance.
I have trouble engaging 1st gear from neutral when stationary. If the bike is moving I have no problem selecting all the gears including 1st.

The clutch has been rebuilt recently with a new centre (old one was grooved causing clutch slipping and dragging), 5 new Barnett friction plates and 4 x 0.080" steel plates were fitted. I have also added an additional steel plate which was surface ground to 0.050" which has resulted in a feather light clutch operation and there is no sign of clutch slipping or dragging. I have used ATF in the primary drive.

Looking at the design of the gearbox it must rely on some residual clutch drag to allow 1st gear to dog with 2nd gear. It appears that the clutch is completely disengaging and the 4 dog pins on 2nd gear are not lined up with the mating holes in the 1st gear which is preventing selecting 1st gear. If I loosen of the clutch cable to deliberately cause some drag I can get 1st gear to engage. Also rolling the bike forward or back about 6 inches allows 1st gear to engage.

I also had this problem before the clutch was rebuilt.

Has anybody got any ideas how to solve this problem or is this normal?

Thanks Tony
 
Norton Gearbox Problem

Hi there, im not sure what it is but mine jumps out of 1st when I pull away from a standing start.
Mick hemmings is an expert on Norton gearboxes in the UK.
He has made a DVD on stripping, repairing & Re-building these gearboxes.
Ive put his website below for you. He does not seem to have an e.mail address but you can fax or phone him with a question, i'm sure he will know whats causing it.
Or you could try putting a question on our web site, its free to register.
http://www.yorkshirenortonownersclub.org.uk/


http://www.mickhemmings.com/

Best of Luck
 
Often the cause is the spring controlling the pawl in the outer case. It can break or be in need of adjustment (bending). Probably unlikely if you get gears OK on the move. Might be excess axial play on 1st laygear (retained by the shoulder on k/s bush) but usually the inner cover stops it moving too far away from the dogs. Check out Old Britts site - TECH - GEARBOX REBUILD, HOW IT WORKS etc. Really good pics and info.
http://www.oldbritts.com/ob_start.html
As for jumping out of gear that could be worn dogs, excess gear movement, worn detent/spring or selector quadrant. Again the Old Britts site is helpful.
 
Thanks for the information.
I dismantled the clutch again and found nothing wrong. Reassembled and adjusted the clutch per the manual, but this time I refilled the primary with engine oil instead of ATF. Went for an extended ride today and no problems selecting 1st while stopped. I'm assuming the new clutch plates were bedding in and rubbing off any high spots.

Tony
 
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