1951 AJS 18S Gear Issues

[C130J]

Hi Everyone and Thanks in advance for any help in figuring out what is wrong with my bike.
After sitting for several Months following the purchase of my 1951 18S, I managed to start the bike after a complete oil service. Unfortunately, I am unable to select a gear out of neutral once the bike is running.
I can easily turn the engine over with the clutch in, and I can rock the bike with the clutch in across all gears, without the engine turning over.
Before I strip the clutch down, I’d like to check there is nothing missing.
One engine is running, trying to select a gear results in grinding of the gears, so clutch is definitely not freeing the gears.
Hope everyone is well and looking forward to getting the bike on the road.

[Rob Harknett]

Sounds like the clutch plates have stuck while standing. Gearbox probable OK. Just give the clutch plates a good clean with petrol. When dry, clean corks with fine sand paper. Try the clutch lever and make sure the thrust / push rod moves OK ( not seized ) Re assemble the clutch make sure the plates separate OK evenly. Go by the book re tightening springs. Then observe plates are separating evenly. If they are not, loosen any that are not allowing plates to open. When the plates open evenly, all may need tightening equally, or the clutch may slip.

[SPRIDDLER]

Welcome to the forums.

As Rob has said, plus.....

Test for stuck clutch plates (with the gears in Neutral) by pulling in the clutch handlebar lever (i.e. disengaging the clutch) and operating the kickstart.
The kickstart should then depress easily through its full range of movement without turning the engine over. If the engine turns over the clutch plates have stuck together.

The Owners Manual has full info about stripping and adjusting the clutch on pages 43 to 48 here:

http://archives.jampot.dk/book/Owners_m ... Manual.pdf

[C130J]

Excellent, many thanks. Looks like next weekend is busy for me too.

[Triumph-Legend]

Plates stuck together. It happens if the bike is left standing for quite a long time.
No Big deal, 51 bike just drop of the N/S foot peg and the primary chain cover. Any oil will fall out all over the floor so don't do this in the living room as it makes the carpet go soggy. Pull in clutch lever and watch the clutch. You will see the pressure plate lift but the rest of the plates will be stuck together.
To save stripping the clutch down for no reason. Though the slots around the clutch basket just use a small screw driver to just gently seperate the plates. A little very light oil dripped into the seperated plates will give a bit of lubrication to the plates. Make sure that the aluminium pressure plate lifts nice and evenly when operating the clutch lever. If not adjust to get a nice flat lifting movement. If the clutch is operating nice and smoothly, put your boots on and go for a run down the road, all should be fine. If the clutch lever feels a bit sticky in use, remove the pressure plate and take the push rod out from the gear box shaft. Clean it up and oil it all over and refit push rod and pressure plate, be sure to allow a bit of free play at the push rod by adjusting the screw at the centre of the pressure plate.
It's not a big job and you should be up and running easilly within a couple of hours. A clutch lever operation that feels hard or gritty is not acceptable. Generally Burman clutches are nice, smooth and pretty robust if set up properly.

PS, Chain oil seals from the club spare work really well and last years with not a drop of oil leaking out. But do not over fill the chain case. The bottom of the chain only needs to pick up a little oil when running. Any oil picked up gets thrown all around withing the case and keeps everthing within well lubricated.

Hmm, 51 motor eh. Nice and soft power, a gentlemans motorcycle. For a bit more poke try some H or SH cams. The H are the post 54 road cam and give nice power. the SH comp, (scrambles), cams make things a bit more interesting. Pull hard low and mid but I think the don't seem to rev out so much at the top end. Maybe I need to tweek a few other bits. Bloody good for hills though. Steve at AMC classic spares has stock these cams.