Possible clutch 'Worm Gear'/cable/lever problem '83 GS750E

[Anonymous]

Had this bike a year, originally imported into England from Canada (apparently 27,000km (possible) I've put another 10,000km) and sorted most problems with the help of my manual. However this clutch problem is driving me mad.

Changed the oil to non-synthetic, new friction plates (not the metal ones) and springs. When engaged, the clutch works and does not slip.

Cannot get the clutch to disengage enough for it not to clunk into gear. I can, but it means the clutch slips beacuse it is the permantly slightly disengaged.

I have followed the manual to the letter on adjusment proceudure for the cable. Losseneing of everthing, then tightening the upright adjuster to take up the majority of the slack. Screwing in till I feel tension on the push rod then turning back a quarter of a turn. Tightening up the bolt. Fine adjustment at the leaver.

A good mechanic advised me to check if the lever that is pulled up that pushes open the 'worm gear' (which also looks a bit worn - No diagram or mentions for this 'worm gear' in my manual) which in turn pushes the rod to disengage the clutch should be between 7 and 9o'clock when slack. I checked and it wasn't it was more like 10 o'clock. When I adjust the cable so that the lever is lower (apprently giving a smoother pull) there is too much slack in the cable by 3-4mm.

The Mechanic also noticed that the clutch lever wasn't standard, although his boss didn't think this was problem as it had plenty of leverage before touching the grip.

I could change the lever or the cable. When I first had it and it was serviced they said they had to replace the clutch cable.... could it be too long if so where could I buy the correct replacement? What about this worm gear are they prone to problem? Don't think it is a cable route problem or lubrication problem.

Any help greatly appreciated as apart from this little problem I reckon this bike will run and run. [/i]

[Billy Ricks]

As long as you have the correct gap between the lever and perch the length of the cable shouldn't matter. It's rather common for it to clunk a bit when you shift to first when you first start the bike. Does it go into the other gears alright and does it continue to clunk after the bike warms up? Did you check the steel plates for crowning and turn the crowns all one direction?

[Anonymous]

cable adjustment / crowning of plates

Thanks Mr. Ricks for taking an interst and the quick reply.

It clunks when warm as well, to the point where I can only just get it into to 2nd from 3rd for example. We put the steel plates back in the same way as they were. Also the steel plates looked in good condition as I had a friends modern un- worn plates to compare them to. What do you mean by crowning and what effect would this have.

You say the length of cable doesn't matter but both adjusters are nearlly fully out in order for it to pull. It really feels like it doesn't push the rod far enough across.

[Billy Ricks]

Lewis,
What I meant by crowning is they can get a bit cupped or dished out. If that happens and you reuse the steels then you have to make sure the plates all get turned so the cupping is the same direction. The cupping could be so slight you don't notice it unless you check with calipers or some other way. If you have the adjusters all the way out it could very well be because of the cable. But if you end up with the correct gap at the lever then I wouldn't think so.

[Anonymous]

cable adjustment / crowning of plates

Thanks Mr. Ricks for taking an interst and the quick reply.

It clunks when warm as well, to the point where I can only just get it into to 2nd from 3rd for example. We put the steel plates back in the same way as they were. Also the steel plates looked in good condition as I had a friends modern un- worn plates to compare them to. What do you mean by crowning and what effect would this have.

You say the length of cable doesn't matter but both adjusters are nearlly fully out in order for it to pull. It really feels like it doesn't push the rod far enough across.

[Billy Ricks]

When you get tension on the cable how much of a gap is there between the clutch lever and the perch it bolts to? You should only have about 1/8".

BTW: It's Billy.

[Anonymous]

clutch cable/pushrod/worm gear/gap/adjustment - gs750e '83

Ok,

I've adjusted the cable by the book. If i have a gap at the clutch lever end of 5mm the clutch will not disengage. If I have not gap it wil just about disengage but will be clunky.

I've now taken the clutch cable out, lubed it with engine oil and it travles fine. The route was fine but checked it anyway. I remembered that when another mechanic looked at it for the slipping problem (and this problem - not disengageing enough) he said he took out a steel ball bearing which he thought shouldn't have been there.

I sorted the sliping problem as I mentioned earlier, which I'm pretty sure was the oil. I did, in the process of trying to sort the slipping problem , change the fibre (not the steel) plates and springs.

Rick has mentioned that the steel plates need to be checked for crowning/warping. I havn't got any caliper to measure them with. So before I buy these and dismantle the clutch again I'm looking at the other side first.

I've looked at Triumph diagram which has a worm gear and push rod. It has steel ball bearing. Does anybody know if their should be one or not?

Once again 1983 GS750E Imported from Canada to England.

Thanks in advance.

[Anonymous]

I reckon you've got a worn clutch level pivot - either in the lever or the mounting block, maybe both.

The hole in the lever starts to wear into an oval after twenty years. As the hole deforms the lever has less travel before it hits against the handgrip and so you can't disengage the clutch sufficiently.

Take out the lever and check the hole. There is probably a little spacer sleeve in there, and it might be worn so it is now C-shaped.

You can fix it with a new lever and mounting block,
or by filling the holes with metal epoxy and drilling as original,
or by turning the sleeve so it pushes the lever forward, and filling the worn away bit behind the sleeve with metal epoxy.
Apply moly grease every few months.

I had the same problem you describe and I fixed it with fix 3.

Kim

[Anonymous]

nice one , thanks for that.

The clutch lever is smaller than standard and not the correct one anyway, so I don't know the age of it. It did have a plastic thing inside which I have just wrecked trying to get the cable free of the lever (which won't help things I'm sure). But I'm going to another one anyway as they are only ?10 second hand. I can't go and get that yet becasue the bike is dismantled at the moment.

I'm determined to get the bottem of this problem. I am off to see if my manual mentions cable lenghth, because both adjusters are on full to take up the slack. Also wring up a few parts places see if they have any in stock (UK a problem as we're never sure if it is for this bike or not GSX/GS)

When I first had the bike, they fitted a new cable so it won't (I don't think be a stretch problem) but they may have fitted the wrong one it seems too long by half an inch.

The lever is a strong contender too along with this ball bearing which may or may not have to be inside the worm gear joing onto the push rod.

will post a note to say how I get on.

[Anonymous]

Ger box / selecter problem '83 GS750E 35k km

So... I ordered new stell plates, cable and lever assembly.

I chnged the lever becasue I said previously it wasn't correct. I aslo changed the cable even though the one on their was correct, I think the wrong lever had caused it to kink becasue it was very stiff.

Changed the steel plates. Operation of the clutch has been transformed and have all the right gaps and does not drag.

However the problem of it clunking from 1st to 2nd and 2nd to 3rd (the sort of clung you get when you first put into gear from cold) it still their and doesn;t go even when warm.

After initially suspecting the clutch, I think it could be a gear selector/box/cush drive problem.

Any easy checks greatly appreciated.

[Anonymous]

Ger box / selecter problem '83 GS750E 35k km

So... I ordered new stell plates, cable and lever assembly.

I chnged the lever becasue I said previously it wasn't correct. I aslo changed the cable even though the one on their was correct, I think the wrong lever had caused it to kink becasue it was very stiff.

Changed the steel plates. Operation of the clutch has been transformed and have all the right gaps and does not drag.

However the problem of it clunking from 1st to 2nd and 2nd to 3rd (the sort of clung you get when you first put into gear from cold) it still their and doesn;t go even when warm.

After initially suspecting the clutch, I think it could be a gear selector/box/cush drive problem.

Any easy checks greatly appreciated.