LAYDOWN GEARBOX BUSHES

The slightest clutch drag will make it difficult to get into neutral when stationary. My clutch works fine and doesn't drag noticeably but I have to grab neutral as I come to a halt. Sometimes if I stop in gear, just trickling forward a foot is enough to get into neutral. I think it's called character on these old bikes.

Ian

It is unlikely that the bushes would cause this problem. I agree with Ian that all you problems are more likely clutch related.

The acid test:

Next time you suffer the problem, keep the clutch pulled and stop the engine. Can you now engage neutral?

If yes, then it is clutch related. If no, then look elsewhere.

I think that a lot of these old bikes (like a lot of old people) get a bit fussed in modern day traffic. The clutch inserts, especially the older type, get hot, they expand (symptom is increased amount of clutch cable free play) causing increased drag which gets them hotter which makes them expand more etc. etc.

If the gear lever is solid like it is trying to move when you try and select neutral, again I would suspect clutch. If the lever travels fully without doing anything then you may have a positive stop mechanism problem.

Do you have problems with other gears? For instance having to have two goes at a gearchange or false neutrals?

Is the clutch cable well lubricated? Do you have the correct handle bar lever assembly?

56, 19s. mongrel . laydown g/box. when i replaced my clutch i fitted the new plates i could only get 4 friction plates to fit there wasn't a half and half plate in there either so didn't bother with one. i fitted a new clutch cable. also fitted an expansion spring to the cable gearbox end to give free play in the cable just a better feel adjustment wise. the clutch works fine can get neutral clutch doesn't slip light operation.

one thing that did make a big difference was fitting the new clutch cable. when the old frayed one got hot it just compressed and you lost the pull of the cable difficulty disengaging the clutch .

.............

just to add. i had a funny gear change it would push straight through two gears and you didnt know which gear you were in until you let the clutch out. someone had packed the gear change indicator shaft with felt tightened in with the bolt and a washer. also the gear indicator arrow was catching. as the two shafts rotate independant from one another i just removed all the offending items, all ok.

Do the test I suggested first.

If you can't find neutral give the exact symptoms. Does the lever go rock solid or does the pawl on the positive stop system miss it's ratchet?

The things that made a big difference on my clutch were, Ensuring no contact between back of clutch center and sleeve gear. Eliminating drum wobble on race. Add very flat plates and really carefull spring adjusment,a bit of end float on the layshaft.,Minimum thin oil in case.A bit of primary chain slack. Any one of these "off" will give trouble , and its usually a combination of several of them.

George will it go into 2nd if not first? Will it change ok when moving, ie get rolling and try to engage and then go up and down through the gears when under power?

If the clutch is dragging you'll probably feel the bike trying to move forward with the clutch lever pulled in second and (especially) in first. Sometimes you can go from 1st to 2nd and vice versa when it's dragging but never hit neutral as the amount of pressure you have to apply to the lever just bounces it over the neutral indent on the cam plate.

I would say that all of this proves conclusively that your problem is clutch related.

Give yourself a pat on the back for successfully rebuilding the gearbox!

As to the clutch problem, measure the distance between the handlebars lever pivot and the centre of the clutch cable nipple. What do you have?

Thanks, just checking!

Does your clutch have the slotted nuts for spring adjustment or the three bolts with flat washers?

If the latter, if the bolts have been substituted at some point, the washers may also have been changed. If they are too big in diameter they can catch within the spring cups causing incomplete clutch lift. The result was that the clutch dragged slightly which became worse when hot.

I actually have 7/8" pivot levers on my '55 Model 88. Yes, I know that these levers are correct for a bike with AMC box, and not the earlier Norton box. With a good clutch, it does give enough lift, and it also gives better leverage on the front brake

Paul

Previously colin_mosley wrote:

I would say that all of this proves conclusively that your problem is clutch related.

Give yourself a pat on the back for successfully rebuilding the gearbox!

As to the clutch problem, measure the distance between the handlebars lever pivot and the centre of the clutch cable nipple. What do you have?

You could of course have 7/8" for the brake and 1 1/16" for the clutch which is what I plan for my ES2.

The 7/8 lever will be easier time pull because of the increased mechanical advantage. The travel will reduce as a result.

Not sure about the 1 1/8 lever.

Have you tried winding the spring screws in less. If you have changed the plates they are probably a better material and you can probably get away with less spring pressure.

Gentlemen,

Good source for quality levers, ball end or not; used many times before & excellent service:

http://www.amcclassicspares.com/Cables%20&%20Control%20Levers.pdf#

Rgds

Steve

I hope this is not seen as a hijack attempt on this thread - as the subject is related I thought more would benefit than if I started a new thread .

I have been experiencing occasional gearchange issues on my 1950 ES2 with lay down box . Gearbox was rebuilt approximately 6 years ago with all new bushes/ bearings / springs using the clubs earlier John Hudson gearbox video .

All worked beautifully for a while then I started to occasionally miss third gear and now third and fourth . Gear lever travels fully but no change is effected. Slightly lifting the lever befor trying again seems to do the trick . Again, this is only an occasional occurrence and seems to happen more often at higher engine RPM .

I can certainly live with it but I would like to know the likely cause in the event it becomes worse .

Any input would be appreciated- Thanks in advance- Richard

Previously richard_tool wrote:

I hope this is not seen as a hijack attempt on this thread - as the subject is related I thought more would benefit than if I started a new thread .

I have been experiencing occasional gearchange issues on my 1950 ES2 with lay down box . Gearbox was rebuilt approximately 6 years ago with all new bushes/ bearings / springs using the clubs earlier John Hudson gearbox video .

All worked beautifully for a while then I started to occasionally miss third gear and now third and fourth . Gear lever travels fully but no change is effected. Slightly lifting the lever befor trying again seems to do the trick . Again, this is only an occasional occurrence and seems to happen more often at higher engine RPM .

I can certainly live with it but I would like to know the likely cause in the event it becomes worse .

Any input would be appreciated- Thanks in advance- Richard

Previously George Phillips wrote:

Something missing Colin?

Sorry, something went wrong. Trying to do it on the phone whilst in the shed and I must have lost it and didn't check.

Anyhow. In reply to Richard's post, this is going to be a problem with the positive stop mechanism. When you operate the gear lever, the pawls on the gear shaft plate are meant to engage with the ratchet plate (some people call it the quadrant) and this moves the selector camplate round into the desired gear.

For some reason, occasionally the pawls are missing their engagement so the gear lever does its full travel without doing any work. When you lift the gear lever slightly this allows the pawls into engagement so now downshifting will work.

Check for wear on the pawls and ratchet plate and tired springs. If wear within the various parts prevents full travel of the ratchet plate, then when the gear lever returns to the central position, the ratchet plate is not in the correct position for the next gear shift and the pawls don't engage.

Hope this helps

Colin

I agree it sounds like a problem with the positive stop mechanism. One thing that's important is to make sure that the light hairpin spring centralises the rocking pawl. If it's slightly off centre, it will change OK in one direction but not the other, and as said, lifting the lever can allow the change.

There is a right way and wrong way up for the spring but I can't at the moment remember which is which......