The BSA A7-A10 Forum

Technical => Clutch, Primary, Gearbox => Topic started by: taylor1960 on 15.11. 2015 19:46

Title: gearbox output shaft
Post by: taylor1960 on 15.11. 2015 19:46
Hi all just want to ask has any one ever repaird the key way on a clutch shaft the tred and taper is ok but key mashed, i was thinking of geting welded and re cut do you think its a job or no *eek*
Title: Re: gearbox output shaft
Post by: morris on 15.11. 2015 22:37
Theoretically it can be done by a professional machinist, but it may cost you as much as a new one. He'd have to weld it, reface the taper and recut the keyway.
I would let the key out. If the taper's a good fit and the nut well tight you don't need it.
Title: Re: gearbox output shaft
Post by: edboy on 15.11. 2015 22:54
as the mainshaft is probably scrap due to the keyway damage you could try to bodge with some mig and weld the woodruft key in situ and avoid a strip down. depends on your skills really.
Title: Re: gearbox output shaft
Post by: Rocket Racer on 16.11. 2015 00:18
The key ways do commonly chip and its not usually problematic if the taper is fine -its the taper that does the work not the key way.
Might pay to post a pic so we can see how bad it is,
a second hand shaft would probably be more cost effective than repair if its that bad.
I'd still fit a key, just so the shaft sits in its usual place on the taper.
Title: Re: gearbox output shaft
Post by: taylor1960 on 16.11. 2015 19:45
Thanks all will post a pic
Title: Re: gearbox output shaft
Post by: taylor1960 on 17.11. 2015 08:51
Here is a pic i have the shaft out of box so no problem welding just wondering wit it afect the temper
Title: Re: gearbox output shaft
Post by: chaterlea25 on 17.11. 2015 17:07
HI,
Eucchhhh *ex* *ex*
Thats nearly as bad as I have seen  *eek* *eek*
Welding will inevitably bend the end of the shaft  *problem*
Looking at that Its likely that the clutch adaptors taper will be damaged as well

I have replaced shafts thet were less damaged  than that!!!
So either bite the bullet and buy a new one from Autocycle engineering or find a good second hand one and clutch adaptor

My 2 cents worth
John
Title: Re: gearbox output shaft
Post by: taylor1960 on 17.11. 2015 17:54
Hi its a bad one ok second hand ones arnt that common @ flee bay  *sad2* will keep lookn i have no clutch eather so on look out for one aswell  *smiley4*
Title: Re: gearbox output shaft
Post by: Rocket Racer on 18.11. 2015 05:34
I've got plenty of good second hand ones if that helps pm me.
Title: Re: gearbox output shaft
Post by: coater87 on 18.11. 2015 10:06
 I wonder if you could not visit the local machine shop and have them cut an identical keyway slot on the other side of the shaft. The only problem you might have with this is contact surface.

 As mentioned its a male taper that does the actual holding. By recutting the keyway you are losing some taper contact surface, but then again you have a new key to back it up also. I doubt the neck-snapping horsepower, huge tire contact surface, and general bad way we treat the restored machines is going to twist the output shaft off.

 Lee
Title: Re: gearbox output shaft
Post by: morris on 18.11. 2015 21:49
Agree with chaterlea John here. That's a really nasty one.
Wouldn't mind to much about losing the temper though. It's of more concern that the heat of the welding may bend the shaft and you'll end up with a wobbling clutch... or worse.
Don't think it's worthwhile trying to repair.
Title: Re: gearbox output shaft
Post by: taylor1960 on 19.11. 2015 19:51
Thanks all i think i will go for 2nd hand one  *smile* now i need a clutch 4spring or 6spring which do U all think is best  *conf*  *????*
Title: Re: gearbox output shaft
Post by: chaterlea25 on 19.11. 2015 20:44
Hi,
Best for 99% of owners and easiest to set up is the 4 spring

HTH
John
Title: Re: gearbox output shaft
Post by: Rocket Racer on 19.11. 2015 21:01
Ah onto clutches  *doh*
If you don't have an an existing half decent 6 or 4 spring clutch then I would seriously consider fitting anything else.
Both 6 and 4 spring can be reliable, however neither are that great. The 6 spring bearing arrangement is notably inferior to the 4 spring, but I dont rate the 4 spring either (its better but). In both instances cobbling together repro parts and good 2nd hand can result in a lot of headaches  *pull hair out*.
I ran a 6 spring for 30 years on my 500 single and it was adequate . I have run 4 springs and they can be OK too. But neither compare to some of the after market clutches with proper bearing arrangements. 
So it does depend what you're starting with; if you have a complete clutch (6 or 4) persevere and it'll save some money and can work. If you have nothing or incomplete/shagged clutch, please seriously consider the expense of starting from scratch.
A decent clutch makes a big difference; you can actually change gear and pull up at lights without stress. *eek*
Suzuki GS550 clutch conversions worth considering, 2nd hand they are cheap as from a wreckers. My road a10 has a converted Suzie clutch and my race bike a BNR  *respect*
Title: Re: gearbox output shaft
Post by: taylor1960 on 19.11. 2015 21:55
Never thought of going japanese  *????* were do U get a conversion kit from i think i can pick up a gs clutch from a mate  *smile*  my project came in boxes wit alot mising  *sad2* no clutch or mag going wit wazel ignition system  *ex*
Title: Re: gearbox output shaft
Post by: chaterlea25 on 19.11. 2015 22:59
Hi All,
Quote
Suzuki GS550 clutch conversions worth considering

Another of the roundtoit jobs in the workshop  *sad2* *sad2*

John
Title: Re: gearbox output shaft
Post by: Rocket Racer on 19.11. 2015 23:01
There are quite a few threads on clutch conversions; if you can have a clutch with a good bearing arrangement the plates lift much cleaner. Most of the issues with 6 (and 4) spring plates result from the basket having too much bearing slop in conjunction with a narrow centre rod lift; so the plates lift crookedly and the basket wobbles. A decent clutch bearing for the clutch basket makes all the difference.
Off the shelf modern clutches are available and worth the investment or if you can access an engineer the gs550 clutch can be adapted.

I've always thought the 6 spring was suitable for a fifties washing machine...  *whistle*
Title: Re: gearbox output shaft
Post by: coater87 on 19.11. 2015 23:23
I know about the Phil Pearson clutch, but who else makes clutches that will fit our bikes? I thought we only had 3 chooses, 4 or 6 spring, or Phil Pearson....
Title: Re: gearbox output shaft
Post by: Rocket Racer on 20.11. 2015 00:21
NEB and Bob Newby Racing both come to mind, I'm sure there are others.
The Phil Pearson one was / is (?) suzuki based.
Or likewise there is the SRM 4 spring pressure plate (to improve the lift method -has a top hat bearing arrangement I recall)

As soon as you start deviating from stock the next question is belt or chain driven.
My locally modified suzuki clutch is still chain drive but I really love my BNR belt drive on the race bike.
I do still run a 4 spring on the 500 single and it works, wouldnt be my first choice but it works.
Title: Re: gearbox output shaft
Post by: Topdad on 20.11. 2015 11:49
Don't know if He's still working but there was a guy in Flint North wales called Tony Hayward ,used to advertise in all classic mags ( don't get them now ) from what I heard his stuff was excellent and cheaper than Pearsons stuff, Bob
Title: Re: gearbox output shaft
Post by: taylor1960 on 22.11. 2015 11:41
Food for thought  *conf* do U just use the japanese plates in bsa basket i have looked @ the treds looks a good job but alot of $ for shop made ones im a real DIY on a budget  *ex* lol   *smiley4*
Title: Re: gearbox output shaft
Post by: Rocket Racer on 23.11. 2015 04:18
Food for thought  *conf* do U just use the japanese plates in bsa basket i have looked @ the treds looks a good job but alot of $ for shop made ones im a real DIY on a budget  *ex* lol   *smiley4*

The plates arent the problem in the beesa clutches, its the naff bearings on the basket that flop about that makes the 6 and to a lesser extent the 4 springs the mediocre clutches they are  *roll*

Starting from scratch on a budget keep your eyes open for a complete or a near complete used 4 spring, these should be cheap enough. Converting a Suzuki one was fairly cost effective and a far superior outcome, but a bit of faffing about.
Title: Re: gearbox output shaft
Post by: taylor1960 on 28.11. 2015 22:22
Hi all have my output shaft on its way to me  *smiley4* also just got a 4 spring clutch centre need plates and  springs etc all good  *smile* realy injoying the forum
Title: Re: gearbox output shaft
Post by: taylor1960 on 16.12. 2015 22:21
Well all got my gearbox back together thanks to Rocket Racer  *smile* built it at work wit my work mate Andy who has a Aerial 500 in out lunch break *conf* hope to get all in frame over Xmass thanks for all your help  *smile*
Title: Re: gearbox output shaft
Post by: Rocket Racer on 16.12. 2015 23:16
Only too pleased to be of help, look forward to seeing it take shape  *wink2*
Title: Re: gearbox output shaft
Post by: bikerbob on 17.12. 2015 08:18
I have 1956 A7 with the six spring clutch and agree that the bearings in the basket do cause problems, but Draganfly have a new modified bearing for the six spring clutch it is bearing casing where you insert the double row of balls and is much easier to fit. I fitted one last year and have just checked it and it is Ok also with this bearing fitted there is now no wobble on the clutch basket. I had a four spring clutch fitted to my Gold Flash for sixteen years prior to selling it  but comparing it to the six spring clutch I now have on the A7 with the modified bearing I see no advantage in changing the clutch provided that they are both adjusted correctly.
Title: Re: gearbox output shaft
Post by: taylor1960 on 17.12. 2015 08:32
Thanks all im still lookn i will have to wate to new year for clutch but if any one has a spare one kicking about let me no  ;)
Title: Re: gearbox output shaft
Post by: taylor1960 on 14.01. 2016 14:35
Now that i have my box built and in the bike thanks to Rocket racer  *smile* i now need a new sprocket it had a 19 tooth is that a best allrounder  *????* as i will only be solo and doing long trips but im also a big lad  *ex* have also a 6spding clutch now to fit thanks to klaus all going well  ;)







Klaus
Title: Re: gearbox output shaft
Post by: chaterlea25 on 14.01. 2016 18:51
Hi,
19 tooth is standard, the usual (easier) way to change the gearing is to change the engine sprocket
gearing is also dependant on the state of tune of the engine
Plenty sprockets on
http://www.ebay.co.uk/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=a10+gearbox+sprocket&_sacat=0

HTH
John
Title: Re: gearbox output shaft
Post by: taylor1960 on 14.01. 2016 20:40
Thanks my box & engine are standard will stick to 19 tooth then   
Title: Re: gearbox output shaft
Post by: Rocket Racer on 15.01. 2016 01:10
on my race a10 i fitted b33 type sprockets so i run 520 chain