The BSA A7-A10 Forum

Technical => Clutch, Primary, Gearbox => Topic started by: Mosin on 15.05. 2019 10:56

Title: Clutching at straws
Post by: Mosin on 15.05. 2019 10:56
Well, I finally managed to achieve the near impossible - a totally oil tight primary drive case. The bike is running beautifully and yesterday I had a lovely 80 mile ride through the Lake District in the sunshine, enjoying every moment, Until...

About five miles from home my gear lever worked itself loose and dropped off (which it is prone to doing).  I realised that this must have been within the last mile or so, so I managed to swing the bike round in the road and slowly ride back looking for it, riding the clutch in second to stop the engine stalling. I eventually found it, and re-fitted it, but by this time there was smoke issuing from the back of the clutch and the casing was scalding hot to the touch. I left it to cool down and tried to start it, but now the clutch was slipping so badly that there was no way I could get it to turn the engine over.

I abandoned the bike and hitched a lift home to collect my car and trailer. This morning I tried it again, thinking, rather optimistically, that it might have cooled properly overnight. No change. Have I completely knackered my clutch plates or is there anything else that I can try before disturbing my oil-tight primary?

I live at the top of a hill, so I was considering having a go at bump starting it, in the hope that that might free things up a bit, but I am not sure that would work either.
Title: Re: Clutching at straws
Post by: KiwiGF on 15.05. 2019 11:49
Well, I finally managed to achieve the near impossible - a totally oil tight primary drive case. The bike is running beautifully and yesterday I had a lovely 80 mile ride through the Lake District in the sunshine, enjoying every moment, Until...

About five miles from home my gear lever worked itself loose and dropped off (which it is prone to doing).  I realised that this must have been within the last mile or so, so I managed to swing the bike round in the road and slowly ride back looking for it, riding the clutch in second to stop the engine stalling. I eventually found it, and re-fitted it, but by this time there was smoke issuing from the back of the clutch and the casing was scalding hot to the touch. I left it to cool down and tried to start it, but now the clutch was slipping so badly that there was no way I could get it to turn the engine over.

I abandoned the bike and hitched a lift home to collect my car and trailer. This morning I tried it again, thinking, rather optimistically, that it might have cooled properly overnight. No change. Have I completely knackered my clutch plates or is there anything else that I can try before disturbing my oil-tight primary?

I live at the top of a hill, so I was considering having a go at bump starting it, in the hope that that might free things up a bit, but I am not sure that would work either.

Check there is free play in the clutch cable? as the plates wear the cable can tighten up and cause slip.
Title: Re: Clutching at straws
Post by: RichardL on 15.05. 2019 15:17
Thank goodness for the optimism and knowledge of folks like KiwiGF.  My call would be that the case must be opened, friction and plain plates inspected and, minimally, tightening of clutch nuts.

I've had the situation where I failed to tighten the clutch adequately, then it was nearly impossible to start. In that case, 400 other riders took off on the DGR before I could get started and ride with one other straggler stranger, who is now a friend.

Richard L.
Title: Re: Clutching at straws
Post by: Mosin on 15.05. 2019 15:53


Check there is free play in the clutch cable? as the plates wear the cable can tighten up and cause slip.

You absolute star! I have just slackened on the cable a bit and it was still slipping. I then slackened it off completely and tried to bump it. After several attempts it fired and I then gradually tightened the cable back up as I was riding along. The plates have now all freed themselves and the clutch and kickstart are both working fine again.

But best of all I didn't need to disturb the primary case! Where would we be without this forum?

Thanks again.  *smile* *smile* *smile* *smile* *smile*
Title: Re: Clutching at straws
Post by: Swarfcut on 15.05. 2019 17:14
Mosin. You ain't done yet. After your next little run, drain off the nice hot  oil. What comes out  will give an idea of how much damage has been done. Strain off the bits or change for fresh as appropriate. The clutch pushrod should be under no load with the clutch fully engaged, so a little slack on the handlebar lever is what you need, don't forget there is further adjustment available on the gearbox clutch lever, under the gearbox end cover inspection plate.

 Get yourself a cheap spare gear pedal, keep in the toolbox. This will ensure your fitted pedal never falls off again!


  Swarfy.
Title: Re: Clutching at straws
Post by: Greybeard on 15.05. 2019 18:34
... ride with one other straggler stranger, who is now a friend.
Something good came of it then :)
Title: Re: Clutching at straws
Post by: Greybeard on 15.05. 2019 18:37
Get yourself a cheap spare gear pedal, keep in the toolbox. This will ensure your fitted pedal never falls off again!
That is why I now carry a spare A10 engine with me!
Title: Re: Clutching at straws
Post by: Sav on 16.05. 2019 07:38
Cable ties! Have the same problem on my M23 and could not find the lever on one occasion.

Small cable tie around the lever doesn't look too unsightly and loosely loop it to the frame or whatever is convenient.

 Lever has not fallen off since!
Title: Re: Clutching at straws
Post by: Mosin on 16.05. 2019 08:45
I was thinking of araldite on the spline. It seems a bit drastic, but providing I could get the spline and lever clean enough it should work. The other idea I had was to use a dremel with a grinding disk to slightly widen the grove in the lever itself, thus allowing it to be tightened up tighter. I have seen some interesting solutions on here where the end of the spline was drilled and tapped and a screw and large washer put in place to hold the lever in situ. That looks effective, but requires a bit of extra work.
Title: Re: Clutching at straws
Post by: muskrat on 16.05. 2019 09:45
I use thin ss lock wire through the slot and around the speedo cable. I also carry a bent 14mm ring spanner. A nice tap fit on the spline that got me 100 miles home after loosing mine!
Cheers
Title: Re: Clutching at straws
Post by: JulianS on 16.05. 2019 10:01
My gear lever dropped off at a very inconvenient time.

Fitted a replacement spindle with circlip which prevents it falling off again.
Title: Re: Clutching at straws
Post by: Greybeard on 16.05. 2019 12:19
My gear lever dropped off at a very inconvenient time.

Fitted a replacement spindle with circlip which prevents it falling off again.
Genius!
Title: Re: Clutching at straws
Post by: Mosin on 19.05. 2019 11:52
I have opted for a cable tie through the groove in the lever and round the back of the speedo cable. It might not be the prettiest fix in the world, but it gets me back out on my bike, and as the wise man once said... "If it is effective: It is right!"
Title: Re: Clutching at straws
Post by: duTch on 19.05. 2019 14:37

 
Quote
....... I have seen some interesting solutions on here where the end of the spline was drilled and tapped and a screw and large washer put in place to hold the lever in situ. That looks effective, but requires a bit of extra work.

 I did that, so maybe that's what you read, but with an ulterior motive to fit remote controls (not radio) but have since realised that the stock placement works just fine anyway, but at least I now don't need to worry about losing the lever....(admission time#1;- It's tapped with unf thread ) *shh*
Title: Re: Clutching at straws
Post by: ironhead on 19.05. 2019 23:12

 ...(admission time#1;- It's tapped with unf thread ) *shh*

at least it wasn't metric *bash*
Title: Re: Clutching at straws
Post by: duTch on 20.05. 2019 00:53

 
Quote
Quote from: duTch on Today at 00:37:00


     ...(admission time#1;- It's tapped with unf thread ) *shh*


at least it wasn't metric *bash*

  It was a long time ago, before I knew about metric, but 6mm is probably closer to BSC than unf anyway (least I think it's unf- better check sometime)
Title: Re: Clutching at straws
Post by: RDfella on 20.05. 2019 09:37
But don't use a 6mm to replace 1/4 - it's a smaller diameter and will strip. If I get a gearlever that won't clamp tight, I use a nut on the bolt end to gain a little extra purchase. High tensile bolts are required here.
Title: Re: Clutching at straws
Post by: duTch on 20.05. 2019 10:11

 
Quote
But don't use a 6mm to replace 1/4 - it's a smaller diameter and will strip......

 Obvious- was just making a flippant observation that may work in an emergency