Author Topic: clutch free but gearbox still engaged?  (Read 702 times)

Offline bigmike76

  • Moving Up
  • **
  • Join Date: Aug 2012
  • Posts: 13
  • Karma: 0
clutch free but gearbox still engaged?
« on: 18.07. 2016 11:41 »
I hope someone has had experience of this problem to hopefully save time and money on doing the wrong thing.

I went out on the bike on the weekend, when I first got going it did crunch into first gear and seemed a bit stiff changing gear, as it was only a quick blast up the road to test after cleaning the carb out I carried on, I got to a junction and could feel the bike trying to pull with the clutch in I then decided to turn around and go bake to adjust the clutch, this seemed odd as it was fine before, then it would not go into first gear at all with the engine running and when it did stalled the bike, after an up hill push home i thought I would have a look at the clutch to see what had happened.

The bike is an ex police alternator model and has the 4 spring clutch on.

1 stripped the clutch down but found nothing
2 carefully assembled the clutch testing on the way

everything was freeing off when the clutch lever was pulled, I could turn the engine over with the nut on the end of the crank with the bike in neutral and in gear, but if I try to use the kick start its fine in neutral but in gear it is turning the back wheel, I locked the back brake on to see if there was just a little drag but it was solid and the kick start wouldn't  move, back in neutral and it was free and the engine would turn off the crank and you could see the clutch free wheeling fine.

What can go wrong in a gearbox to cause this, and can I rebuild the box without taking it out of the frame, I want to be riding not stuck in the garage!!!!

any suggestions greatly received

Offline duTch

  • Ricketty Rocketty Golden Flashback
  • Wise & Enlightened
  • *
  • Join Date: Oct 2011
  • Posts: 4540
  • Karma: 41
Re: clutch free but gearbox still engaged?
« Reply #1 on: 18.07. 2016 11:51 »

 
Quote
but if I try to use the kick start its fine in neutral but in gear it is turning the back wheel, I locked the back brake on to see if there was just a little drag but it was solid and the kick start wouldn't  move,

 Not too sure of much else but the above is normal; They have to be in neutral to kickstart.
Only thing I can think of at the mo is your clutch cable has gone out of adjustment, do you have cable adjusters?
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
Australia

Offline bigmike76

  • Moving Up
  • **
  • Join Date: Aug 2012
  • Posts: 13
  • Karma: 0
Re: clutch free but gearbox still engaged?
« Reply #2 on: 18.07. 2016 11:56 »
I have adjusters on the cable, and I have over adjusted them to see if it would free off when the lever is pulled, the clutch would of slipped if riding with these settings but the gearbox is still engaging the back wheel and the clutch is spinning free

Offline duTch

  • Ricketty Rocketty Golden Flashback
  • Wise & Enlightened
  • *
  • Join Date: Oct 2011
  • Posts: 4540
  • Karma: 41
Re: clutch free but gearbox still engaged?
« Reply #3 on: 18.07. 2016 12:13 »

 Mike, I'm a bit baffled *conf*.  I can only make suggestions just now.
With the rear wheel off the ground (centre stand), in gear with the clutch in (jam a small bean can or similar over the bar-end and lever or use a zip tie or rope/jubilee clip whatever)....now where was I *eek*

 ^^^>>>> Turn the rear wheel; does it change gear easily or make noises?? There will be a bit of resistance but not a lot.

 Don't freak out, but the only thing I can think of is I'm kinda thinking that the sleeve-gear bush may be binding *dunno*
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
Australia

Offline a101960

  • Wise & Enlightened
  • *
  • Join Date: Sep 2007
  • Posts: 1034
  • Karma: 11
  • BSA RGS BSA C12
Re: clutch free but gearbox still engaged?
« Reply #4 on: 18.07. 2016 12:38 »
It is quite possible that the clutch push rod ends are no longer hard causing the rod to shorten due to wear. However before you look at things like that, have you checked the basic clutch set up procedure? For example where is the operating lever on top of the gearbox pointing when the clutch is disengaged (clutch handle bar lever pulled in toward the handle bar)? It should be at a right angle to the push rod (parallel to the frame). When the clutch is engaged the lever should be at an angle to the right. If is not then remove the gearbox inspection cover and adjust the adjustment screw by unlocking the lock nut and turning the screw with the handle bar lever pulled in to the handle bar until it is. Then  adjust the cable to give around 1/8” free play on the handle bar lever. It could be that the clutch springs  need adjustment and setting up. I do this with a dial gauge to ensure that the plates are lifting squarely. If the springs are not equalised and the plates are not pulling up squarely than it will cause the clutch to drag, and as everything warms up it will only get worse. How much oil have you got in the primary chain case? From empty it should be 8 fluid ounces  (225cc). I use ATF but engine oil was specified by BSA. As Dutch pointed out to kick the bike over it must be in neutral, you cannot start the bike in gear. Sometimes if the rear wheel is clear of the ground you might see the rear wheel revolve in neutral that is normal and nothing to worry about.

John

Offline bigmike76

  • Moving Up
  • **
  • Join Date: Aug 2012
  • Posts: 13
  • Karma: 0
Re: clutch free but gearbox still engaged?
« Reply #5 on: 18.07. 2016 13:41 »
Thanks for the replies,

I did set the clutch up according to some posts on this site as it is the most obvious thing, and the actuating arm on the gearbox is level when pulled in, I have just taken the pressure plate off the clutch now to get rid of all possible resistance and the same thing is happening.  In gear the back wheel is turning when pushing the kick start down and the same if the wheel is locked you can't move the kick start, all this with basically no clutch on the bike!!!

stumped to say the least.

I am aware that you can't start the bike unless its in neutral but if it was in gear and with the clutch pulled in the kick start would still go down with no resistance I would imagine.

Online Triton Thrasher

  • Scotland
  • Wise & Enlightened
  • *
  • Join Date: Feb 2009
  • Posts: 1474
  • Karma: 20
Re: clutch free but gearbox still engaged?
« Reply #6 on: 18.07. 2016 18:04 »
In gear the back wheel is turning when pushing the kick start down and the same if the wheel is locked you can't move the kick start, all this with basically no clutch on the bike!!!

That is how it is made. It has to do that. 

Quote
if it was in gear and with the clutch pulled in the kick start would still go down with no resistance I would imagine.

Yes- you are imagining that.

Most japanese bikes with kickstarts had "primary kickstarts" and could be kickstarted in gear with the clutch lever pulled,  but no British bikes so far as I know.

Online beezermacc

  • Resident Legend
  • *****
  • Join Date: Dec 2011
  • Posts: 899
  • Karma: 36
  • Not for the purist!
    • Priory Magnetos Ltd.
Re: clutch free but gearbox still engaged?
« Reply #7 on: 18.07. 2016 18:08 »
The kickstart quadrant is meshed onto the mainshaft so, when you move the kickstart, the mainshaft turns. If the bike is in gear the mainshaft turns the layshaft which turns the sleeve gear which turns the chain, which turns the back wheel. The clutch disengages the engine from the gearbox, it does not disengage the gearbox from the back wheel. What you are experiencing is normal.
Priory Magnetos Ltd - A10 spares, magneto and dynamo refurbs. www.priorymagnetos.co.uk

Offline bigmike76

  • Moving Up
  • **
  • Join Date: Aug 2012
  • Posts: 13
  • Karma: 0
Re: clutch free but gearbox still engaged?
« Reply #8 on: 18.07. 2016 19:36 »
Thanks

Just been out in the garage and discovered everything you have said (feel stupid) I have even stripped the gearbox!!!!! though I did find some issues the main shaft has a slight bend on it not much and the kickstart rachet won't be long until it gives up the ghost, so not a complete waisted effort.

thanks for all of your input, I will get the new parts and see how it goes, but just another thing while its fresh in my memory.

Does the clutch need a copper thrust washer behind the hub "like triumph ones" as there is one fitted and looks very scored, it doesn't really fit on the hub very well,(not enough of a flange) the diagram in the book does not show one, I did wonder if someone had done this to take up slack.

Offline a101960

  • Wise & Enlightened
  • *
  • Join Date: Sep 2007
  • Posts: 1034
  • Karma: 11
  • BSA RGS BSA C12
Re: clutch free but gearbox still engaged?
« Reply #9 on: 18.07. 2016 19:45 »
Quote
but no British bikes so far as I know.
TT I think that you can kick start a Bantam while it is in gear if I remember correctley. It was a long time ago that I owned one though! And I suppose to be fair the Bantam was a German design that BSA merely played about with.
John

Offline Clive54bsa

  • A's Best Friend
  • ***
  • Join Date: May 2012
  • Posts: 126
  • Karma: 1
  • Orange SoCal
Re: clutch free but gearbox still engaged?
« Reply #10 on: 18.07. 2016 23:53 »
I agree with Dutch, a sleeve gear binding, I has my 54 GF gearbox rebuilt sometime back and the mechanic tightened the sleeve gear with an impact wrench, and I experienced the same symptoms.


'54 GF,  '61 SR,  '71 B50MX

Offline cyclobutch

  • Wise & Enlightened
  • *
  • Join Date: Aug 2010
  • Posts: 1435
  • Karma: 14
Re: clutch free but gearbox still engaged?
« Reply #11 on: 19.07. 2016 08:32 »
Quote
but no British bikes so far as I know.
TT I think that you can kick start a Bantam while it is in gear if I remember correctley. It was a long time ago that I owned one though! And I suppose to be fair the Bantam was a German design that BSA merely played about with.
John

No - not on a Bantam either. I was trying this just Saturday when it was probably in 3rd gear ... after I had come off.
Various, including ...
'58 Iron Head Flash Bitza


Offline coater87

  • Wise & Enlightened
  • *
  • Join Date: Jul 2008
  • Posts: 1181
  • Karma: 6
Re: clutch free but gearbox still engaged?
« Reply #12 on: 19.07. 2016 13:34 »
Quote
but no British bikes so far as I know.
TT I think that you can kick start a Bantam while it is in gear if I remember correctley. It was a long time ago that I owned one though! And I suppose to be fair the Bantam was a German design that BSA merely played about with.
John

No - not on a Bantam either. I was trying this just Saturday when it was probably in 3rd gear ... after I had come off.

 Sorry to here that, nothing broken/torn/swelled up/ or dislocated I hope?

 I could fly 30 feet through the air, land flat on my back and be fine when I was young.

  Now, I step off the porch step wrong and I dont move for a few seconds hoping my hips still work... *sad2*
Central Wisconsin in the U.S.

Offline cyclobutch

  • Wise & Enlightened
  • *
  • Join Date: Aug 2010
  • Posts: 1435
  • Karma: 14
Re: clutch free but gearbox still engaged?
« Reply #13 on: 20.07. 2016 12:29 »
Sorry – I probably inserted that line there to invite questions for purposes of my own aggrandisement. But here’s the story;
I have no great enthusiasm for Bantams as it happens, but still had the bike kicking around that my wife learnt to ride on back in the late 70s.
It was a slightly ropey but complete D14/4, and rather than sell it I kind of stripped it out and hard tailed it. In part as a dry run for trying similar ruination of my Sportster.
I then entered it into the road bike class at the Dirtquake races run at Kings Lynn speedway last weekend.

http://sideburnmag.blogspot.co.uk/2015/12/dirt-quake-2016.html

The bike ran like a champ, and with low power and weight and fitted with knobblies it actually stuck to the shale surface like the proverbial does to a blanket.
I made 3rd in my first heat in a field of 12, after forcing it up the inside of some brave soul out there on a ZRX1200.
I was running 4th in the second heat, still riding it harder and harder, and which should have been enough to qualify for the final, when I threw it all away on turn four of the penultimate lap.
So a low side get off onto a ‘soft’ shale track at a speed that felt like 90 but was probably nearer 20. The most comfortable bike related comeuppance I’ve ever had.
Sadly the bike flipped and did both sides, so is looking even more second hand right now.   
Various, including ...
'58 Iron Head Flash Bitza