Transmission -still - won't shift properly.

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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 just did up a 71 .Did the tranny mainshaft roller bearing while in there. I had the same problem until I realized I had it in my 68 years ago as well.Shifts up and down when shut off as well as when running,but could not get it into neautral. I remembered from my 68 to give the primary chain more slack.Problem fixed. It just takes a little. When you are checking it with your finger through the inspection hole it is easy to think it is loose enough but it is tight.
Bruce
 
bchessell said:
I just did up a 71 .Did the tranny mainshaft roller bearing while in there. I had the same problem until I realized I had it in my 68 years ago as well.Shifts up and down when shut off as well as when running,but could not get it into neautral. I remembered from my 68 to give the primary chain more slack.Problem fixed. It just takes a little. When you are checking it with your finger through the inspection hole it is easy to think it is loose enough but it is tight.
Bruce

Thanks Bruce - but - we've tried it even with the Primary way too loose - and it still doesn't work right - doesn't seem to matter if the primary is loose or tight it still won't shift right - it shifts fine when the engine isn't running - it's only with the engine running - and the clutch pulled in of course - that it won't shift - it's like its jammed in gear - very frustrating problem...nobody has ever seemed to of heard of this problem either - I've been working on this so long that I'm almost ready to just give up....thanks again.
Paul.
 
Commando850 said:
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.

On my '70 the adjuster has a thick side and a thin side, i.e. the threaded stem of the moveable part is offset to the outside.

Grasping at straws - If you look at the clutch with the primary cover off, does the center stop turning when you pull in the lever ?

Greg
 
gjr said:
Commando850 said:
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.

On my '70 the adjuster has a thick side and a thin side, i.e. the threaded stem of the moveable part is offset to the outside.

Grasping at straws - If you look at the clutch with the primary cover off, does the center stop turning when you pull in the lever ?

Greg

From what I remember - I wasn't looking for that specifically - but I believe that everything kept turning when the lever was pulled in - should it turn or should it stop???
 
Tell me about your clutch plates and the grooving of the center hub and basket. Your symptoms sound a lot like a sticky clutch which could result from a trany oil invasion or "ruts" worn into the clutch basket or center hub grooves, any of this would make complete disengagement hard to do when the machine was running and at a stop, causing enough "loading" to make it hard to shfit into any selection.

RS
 
Commando850 said:
From what I remember - I wasn't looking for that specifically - but I believe that everything kept turning when the lever was pulled in - should it turn or should it stop???

Pulling in the lever should decouple the outer basket from the inner hub. The inner hub and fibre plates should stop turning, but it might be hard to see. If it doesn't you might have a problem with your spring not lifting uniformly or the plates are all sticky.


Greg
 
Not sure about a '74 but my '72 has a spacer that goes thru the top trans mount bolt on the drive side between trans and inner cradle. Don't know if missing this spacer would cause symptoms
 
hi gjr and commando,pulling the clutch in ,in neutral wont stop the inner hub from spinning,however it will stop when the bikes put in gear,but you wont see it because of the spinning diaphragm spring
 
Okay, Let me try again. Is the clutch dragging enough to load up the transmission making it hard to shift into neutral at a stand still ?

Greg
 
Sorry for taking so long to get back to you guys - and much thanks for all the help - I try and answer some questions,

I does indeed seem like the clutch is dragging - and that is causing my problem - but i have no idea why. I just had my clutch apart. All of the plates are in excellent condition. There is no "notching/grooves" in the outer clutch basket splines - and the inner clutch hub and bearing are brand new with no "notching/grooves" whatsoever.

I checked - and I do have the proper spacer installed - in the proper place - on the upper transmission mount bolt. My transmission adjuster is not "offset" as previously described - so i have ordered a new one - along with all new hardware for the upper and lower transmission mounts. I'm going to replace all the mounting hardware - when the parts get here - and give it another try.

If that doesn't work I'm going to dismantle the primary completely and see what I can see...

If I don't see anything wrong with the primary...I guess I'll have to dive into the box...again!!!....urghhh!!!

Thanks for the help guys - if you have any new ideas let me know - I'd really appreciate it.

Paul.
 
Check to see if the diaphram spring is lifting squarely. I don't remember how mine looked, but it was obviously crooked. I think the fingers were what looked 'off'. That would be an easy fix.

Greg
 
Ah...you have a new centre.....is it one of the ones that binds on the clutch chainwheel????
 
gjr said:
Check to see if the diaphram spring is lifting squarely. I don't remember how mine looked, but it was obviously crooked. I think the fingers were what looked 'off'. That would be an easy fix.

Greg

I had a look at that - to see if it was lifting evenly all the way round - It looked OK to me but I will check it again - I have another spare spring I'll maybe install my spare and see if that cures it...I fear though - if it was obvious I think I would have noticed it as I was looking at this as a potential problem...doesn't hurt to check again though...

Thanks!
 
Seeley920 said:
Ah...you have a new centre.....is it one of the ones that binds on the clutch chainwheel????

It didn't seem to bind when I installed it - I remeber though that - with it off the bike completely and the new center and new bearing installed - I could hold the center and spin the chain wheel. It spun pretty freely - but I remember there was a slight "swishing" noice - like very light contact - I didn't figure it mattered but maybe it does !!! it didn't seem to slow the free-wheeling of the chain wheel at all....hmmmm...maybe it gets worse when it heats up?
what do you think?

thanks much!
 
Commando850 said:
Seeley920 said:
Ah...you have a new centre.....is it one of the ones that binds on the clutch chainwheel????

It didn't seem to bind when I installed it - I remeber though that - with it off the bike completely and the new center and new bearing installed - I could hold the center and spin the chain wheel. It spun pretty freely - but I remember there was a slight "swishing" noice - like very light contact - I didn't figure it mattered but maybe it does !!! it didn't seem to slow the free-wheeling of the chain wheel at all....hmmmm...maybe it gets worse when it heats up?
what do you think?

thanks much!

Where in the world are you?
 
swooshdave said:
Commando850 said:
Seeley920 said:
Ah...you have a new centre.....is it one of the ones that binds on the clutch chainwheel????

It didn't seem to bind when I installed it - I remeber though that - with it off the bike completely and the new center and new bearing installed - I could hold the center and spin the chain wheel. It spun pretty freely - but I remember there was a slight "swishing" noice - like very light contact - I didn't figure it mattered but maybe it does !!! it didn't seem to slow the free-wheeling of the chain wheel at all....hmmmm...maybe it gets worse when it heats up?
what do you think?

thanks much!

Where in the world are you?

Saint John, New Brunswick, Canada
 
While you're in there check to see that the large coiled clip that retains the spring is fully seated
 
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