- Joined
- Oct 5, 2009
- Messages
- 20
I posted earlier about a problem I was having with my 1974 Norton Commando 850. The problem is that the Transmission won't shift properly when the bike is running. When the bike is not running you can shift it up and down through the gears no problem - just jiggle the rear wheel and the gears snick right in without much effort. If you drive the bike up the road it shifts fine up through and down through all gears as long as the bike is moving. When you stop the bike - clutch pulled in - in first gear it takes an incredible amount of pressure to shift up out of first - so much that you go right past neutral into second. It then takes so much pressure to try and shift it down from second into first or neutral that I'm afraid of breaking something. The only way is to shut the bike off - once you do that it will snick out of second into neutral or first with very little effort.
I have a friend who used to own a Norton dealership - back in the day - come over to help me. He's worked on countless Norton's. I showed him the problem. First he checked my clutch adjustment and told me that it was bang-on - we then completely disassembled the clutch and found nothing wrong. He informed me that my clutch was in very good shape. We reassembled the clutch and adjusted the primary chain as he thought it was slightly too tight - taking care to ensure the rear chain was adjusted properly at the same time. We put everything back together but it still didn't work properly.
We then proceeded to remove the outer gear-box cover. There again - we found nothing wrong. The shift quadrant wasn't overly worn nor was it installed improperly. The spring on the shift mechanism had the correct clearance and was installed properly - it wasn't upside-down as can easily happen. I shifted the bike up and down through all gears by using a screwdriver in the shift arm - with the outer cover off - and the shifting was light and positive
Again we reinstalled everything and it still doesn't work properly.
When we adjusted the primary drive chain - as per the manual - we loosened the upper and lower transmission bolts - when we re-torqued these bolts back up to the recommended 55 ft-lb's we noticed that this tightened the chain considerably - we loosened them back up and slacked the chain off even further so that when we did re-torque it tightened it chain back up to the proper adjustment - again making sure the rear chain did not get over tightened.
Again - no luck - So we called another Norton expert in our area - He has never heard of a problem such as this. He told us to check all of the usual suspects that we had already checked. Then he said it could be a bad bearing or a bent lay-shaft, or main shaft - maybe - really he had no idea???
I did notice that the adjuster for the primary drive chain does not line up with the huge collar that the upper transmission bolt goes through. When you torque this upper bolt the adjuster seems to bend in toward the cradle - however it seems to hold it in place??? - I checked the manuals and parts books and it doesn't show any spacers for the bolt on the right-hand side of the bike - just one on the left side (primary) - on the inside of the cradle which is in place.
So...I am as a loss as to what is wrong with this bike. I reassembled the transmission last winter after fixing stripped drain bolt threads. At that time everything was in spec and it has all new bearings including a roller bearing replacement in the lay-shaft.
I have had this bike for years and it used to work fine - Neither I nor my former Norton dealer friend still do not have any idea what is wrong. We were both pretty discouraged. I can completely disassemble the Primary and Transmission...again...but I really don't want to do that only to put it all back together and still have it not work properly.
I'm looking for any and all advice - Should I maybe just ditch this tranny and buy a new one from Andover Norton? I am totally stumped. I've worked countless hours on this and haven't gotten anywhere.
Thanks in advance.
Paul.
I have a friend who used to own a Norton dealership - back in the day - come over to help me. He's worked on countless Norton's. I showed him the problem. First he checked my clutch adjustment and told me that it was bang-on - we then completely disassembled the clutch and found nothing wrong. He informed me that my clutch was in very good shape. We reassembled the clutch and adjusted the primary chain as he thought it was slightly too tight - taking care to ensure the rear chain was adjusted properly at the same time. We put everything back together but it still didn't work properly.
We then proceeded to remove the outer gear-box cover. There again - we found nothing wrong. The shift quadrant wasn't overly worn nor was it installed improperly. The spring on the shift mechanism had the correct clearance and was installed properly - it wasn't upside-down as can easily happen. I shifted the bike up and down through all gears by using a screwdriver in the shift arm - with the outer cover off - and the shifting was light and positive
Again we reinstalled everything and it still doesn't work properly.
When we adjusted the primary drive chain - as per the manual - we loosened the upper and lower transmission bolts - when we re-torqued these bolts back up to the recommended 55 ft-lb's we noticed that this tightened the chain considerably - we loosened them back up and slacked the chain off even further so that when we did re-torque it tightened it chain back up to the proper adjustment - again making sure the rear chain did not get over tightened.
Again - no luck - So we called another Norton expert in our area - He has never heard of a problem such as this. He told us to check all of the usual suspects that we had already checked. Then he said it could be a bad bearing or a bent lay-shaft, or main shaft - maybe - really he had no idea???
I did notice that the adjuster for the primary drive chain does not line up with the huge collar that the upper transmission bolt goes through. When you torque this upper bolt the adjuster seems to bend in toward the cradle - however it seems to hold it in place??? - I checked the manuals and parts books and it doesn't show any spacers for the bolt on the right-hand side of the bike - just one on the left side (primary) - on the inside of the cradle which is in place.
So...I am as a loss as to what is wrong with this bike. I reassembled the transmission last winter after fixing stripped drain bolt threads. At that time everything was in spec and it has all new bearings including a roller bearing replacement in the lay-shaft.
I have had this bike for years and it used to work fine - Neither I nor my former Norton dealer friend still do not have any idea what is wrong. We were both pretty discouraged. I can completely disassemble the Primary and Transmission...again...but I really don't want to do that only to put it all back together and still have it not work properly.
I'm looking for any and all advice - Should I maybe just ditch this tranny and buy a new one from Andover Norton? I am totally stumped. I've worked countless hours on this and haven't gotten anywhere.
Thanks in advance.
Paul.
