The BSA A7-A10 Forum

Technical => A7 & A10 Engine => Topic started by: brackenfel on 29.01. 2010 16:42

Title: Problems Removing A10 Primary Chaincase Inner
Post by: brackenfel on 29.01. 2010 16:42
Dear All,
I am new to this forum but have read quite  a number of posts so far.. I'm also new to BSAs (but not old bikes - have Velocette, Laverda, Matchless in bits etc etc ) having recently decided to sell my little VFR400 and buy a 1961 A10 as a regular ride...
That was the plan......  However.....
Although I rode the bike home & around a bit once the MOT haad expired I thought I'd "just check a few things over"!! Now there are bits of it everywhere.
Gear change wasn't great so I tackled the clutch. 20 tooth engine sprocket which is a bit unusual, 4 Spring clutch which had been wound up far too tight (had to drill 2 of the spring retainers to get them to undo). I have discovered that previous owner had a thing about grease (see photos to prove!!) which probably explained this when the clutch slipped it got tightened up some more..

As the bike leaks oil a lot on the LHS I thought I'd get the primary inner off as well - this would also give me a chance to look at the gearbox sprocket (the bike is a bit "buzzy" in top gear).
Now the problem.. The bike is fitted with the full rear chain enclosure. This has resulted in a chain so slack it's a wonder it stayed in place as PO had fed copious amounts of grease thru the inspection hole but clearly hadn't adjusted it! So, the back bits have been loosened & pulled back..
I can't get the primary case off though as the front bit of the enclosed rear chaincase unit is bolted to it with nuts somewhere round the back. The splined bit that the LHS footrest is still in place as that won't come out due to the same bit of pressed tin!!

Has anyone found an easy way here??  I'm about to get the rear wheel out as well to see if I can see any more from the back but am conscious that if I don't stop soon this thing will never get back on the road & will become a major "project"..

All suggestions appreciated..

Thanks

Adrian

PS thansk for your patience - there will be more questions...
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: Desburnett on 29.01. 2010 17:01
Hi,

With the clutch basket removed you should see the heads of the two retaining screws that secure the sliding seal cover plate and secure the front section of the rear chain guard. If you cant get a spanner on the nuts at the back drill out the two fixing screws, new ones are avaliable and are cheap.

Cheers, Des
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: muskrat on 29.01. 2010 19:10
G'day Adrian,
                 Welcome to the group. So thats why they call old mechanics grease monkeys. i have never had an enclosed chain guard myself, but by the sound of it you should remove the wheel and guard just to clean out all the grease. You might then be able to get to the nuts. Failing that use Des's method but be careful as the bolts have a shoulder that sits against the inner primary cover. It would be a good idea to replace the gearbox sprocket and seal while your in there. You may be able to clean the grease off the clutch plates with petrol but I would throw in new friction plates, springs and chain. The 4 spring clutches are sweet when set up right.
Remember, there is no such thing as a silly question ( just silly answers ).
Cheers
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: LJ. on 29.01. 2010 19:12
Hi Adrian! Welcome along to the forum...

Yea strewth! your right about the Previous owner liking grease! What a mess, a complete good clean out of all that muck is in dire need. That primary chain also will need to be tighter than what I see in the picture. Like Des says there are two very thin headed bolts (normal) behind the clutch wheel that you need to undo, you'll probably need a clutch hub puller too as its nigh impossible to remove with out damaging it, don't ask me how I know!

'Oil Leaks a lot' hmmm wonder where from if the primary was bunged full of grease! You need a thicker oil in the gearbox, I use straight 50. While the clutch is off and you investigate the 'buzzy' gear check the oil seal just near the gearbox sprocket.

There's likely to be some more adjustments to be made while getting to know the bike but in time it'll be a really nice reliable bike to ride.

cheers! LJ.

Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: rocket man on 29.01. 2010 23:06
hi adrian welcome to the forum looks like a grease monkeys been at that primary
should only have oil in it looks like your going to have a lot of fun with your a10
there a good ride and a great sound




dave
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: BSA_54A10 on 30.01. 2010 02:22
The usual reason for greasing the primary is either ignorance or oil leaks.
Check the bolt holes in the primary you will probably find they have all "pulled out" so will need a little counter sink to allow the outer case to sit flat on the sealing face.
Naturally new chains and sprocket are in order and I would go for a new sliding plate as well.
The new aftermarket ones have far better oil tightness that the old ones.
Pack out the space between the gearbox sprocket and the inner cover sliding place with felt washers
Glue a thick fine grain neoprene cork gasket on the sliding plate and that will just about end oil leaking from the primary.
You will have to make this gasket yourself and buy the material from an engineering supply store , not an auto parts shop , the latter only keep cheap stuff which is not worth the time spent cutting the gaskets. If you are within striking distance of a port then go to a marine engineering supply store which is where the stuff that "can not fail in service " is  stocked. Ditto of aero supply stores, but they have aero prices for the same materials that the marine shops stock at marine prices.

There is a vent on the primary case which doubles as a chain oiler. It has an under cut in the inner side so that gasses and some oil can escape which dribbles down onto the drive chain, don't block it off.

Clutch has all the same problems as any other Pommie dry clutch has so you should be familiar with those. 
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: 1660bob on 30.01. 2010 08:52
Hi Adrian, welcome to the forum.Good luck seems like you have plenty to be going on with for now!!!!-I couldn`t resist a chuckle at photo 1-the arc of a probing finger around the pri case filler cap- I can imagine your expression at withdrawal of said digit dripping with grease "WTF......" Sympathies, Mine certainly turned into a "project" (of biblical proportion) and my "quick once over" turned into a horror story....Still, I suspect many on this forum have been there, and eventually come through with a decently sorted bike to enjoy... I`m a long way off yet but i keep focussed on some of the piccies of finished bikes herein....great therapy and incentive.Incidentally-look out for the small spacer(may be washer(s))part No:42-4792 between frame and inner primary casing where it is bolted to at bottom rear end(pic 2)-easily missed in all that gloop!Best of Luck-Bob.
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: LJ. on 30.01. 2010 09:31
Quote
Incidentally-look out for the small spacer(may be washer(s))part No:42-4792 between frame and inner primary casing where it is bolted to at bottom rear end

Indeed your right about that spacer Bob and there was a thread devoted to this spacer sometime ago, most here seemed to have made up their own spacer as I don't think there is one size suitable for all bikes. Likely there will be two or three millimetres difference and again that could be the difference to clutch operations and leakage. I was not aware though that it also has a part number so thanks for that.
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: The General on 30.01. 2010 09:50
On my 62 Super Rocket the inner primary case can be removed with the front chain guard still attached.
You have to remove the rear chain and other pieces of the guard.
It makes it a lot easier to get to the two bolts of the front guard.
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: brackenfel on 31.01. 2010 09:57
Dear All,
Many thanks for the replies received, much appreciated..
I do have some new plates & centre rollers & have added various other items now thanks to suggestions to my list for the Bristol Show or the Shepton VMCC jumble...
A mate lent me a puller to get the clutch centre out which was no trouble. The clutch basket is notched by the plates, I presume the usual filing can be used here? I'm afraid due to budgets I won't be replacing everything in sight at this stage, bit of a "make & mend" really.
Thanks for the warning about the frame space at the rear mounting, typically I don't think mine has one - another for the list!

I'll get the rear wheel out next as I want to replace the tyre anyway and go from there..
Bob was spot on with the area around the primary inspection plug - just what I thought when I did a bit of "digital" investigating!! Tell you one thing though, although the plates didn't enjoy it once you wipe the grease off it leaves things spotless!!

Just to prove it wasn't a one off I attach a couple of pics of the other side....


Thanks again for the warm welcome, I will be back to let you know how things go & probably with more questions..

All the best,

Adrian
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: rocket man on 31.01. 2010 14:25
looks like the old owner loved grease must have had shares in it
id look in the crankcases next and oil tank are they full of grease also   *smile*
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: LJ. on 31.01. 2010 17:55
Well... congrats to the previous owner regarding the amount of grease in the dynamo chain area as that is not a bad thing. Just that you need to be sure the cork gasket is good and the dynamo is pushed well up to it.
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: BSA_54A10 on 02.02. 2010 10:22
The dynamo chain is supposed to run in grease.
I put Duckhams chain grease in there which melts at running temperatures
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: brackenfel on 02.02. 2010 12:39
Many thanks for the replies.. Point taken about the grease, I'll put some fresh in the dynamo chain area...

However on the other side I've had another look & have decided on the "blow it" (or words to that effect!) approach... I still can't shift the inner, the casting with a spline that the LHS footrest fits on is in the way & won't come out.. Looks like it was put in place & then the engine put in afterwards!.
I'm worried if I do get the 2 nuts off the back of the slider I'll never get them on again, ditto if I remove the rear chain?.

Using a mirror & inspection light I can see up into the gearbox area & have cleaned it up a bit. I'm now going to refill the gearbox & if it doesn't leak in the sprocket area I'm going to chuck the whole thing back together.
I want to try & squeeze a new gasket around the crank area at the front of the case but am abandoning looking at the gearbox sprocket. I started this 'cos of the oil leaks & poor gear selection, the bottom line is that I need the bike to ride & not another project (I have 2 others that have been waiting a long time already..)

A quick question...
This is a 1961 bike (reg'd in '62) and according to the Draganfly catalogue uses 2 gaskets behind the crank end of the primary chaincase, one for other models. Anyone know if this is 2 together or one either side of the steel plate?  In my spare bits that came with the bike is a gasket for the crank end that is quite thick ( a bit like me !) , about 1mm , can I use this place of 2 thinner ones ??

Looking at part lists the "spacer" used at the rear seems to vary with year too. As it fits behind the frame, I presume this spacer goes between the frame & case (again the catalogue doesn't make this clear, showing at the nut end). There doesn't naturally seem to be a gap, should I force issues to create one by inserting a thin spacer??

As usual any thought appreciated..

Cheers,
Adrian
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: RichardL on 02.02. 2010 16:33
Many thanks for the replies.. Point taken about the grease, I'll put some fresh in the dynamo chain area...

But not as much and of a better grade, I trust.  

However on the other side I've had another look & have decided on the "blow it" (or words to that effect!) approach... I still can't shift the inner, the casting with a spline that the LHS footrest fits on is in the way & won't come out.. Looks like it was put in place & then the engine put in afterwards!.
I'm worried if I do get the 2 nuts off the back of the slider I'll never get them on again, ditto if I remove the rear chain?.

Someday that footrest will have to come off, will doing it then be easier and more productive than doing it now? I suppose you already have this drawing of the chaincase, but, what the heck. http://www.a7a10.net/forum/index.php/topic,430.msg2163.html#msg2163

Using a mirror & inspection light I can see up into the gearbox area & have cleaned it up a bit. I'm now going to refill the gearbox & if it doesn't leak in the sprocket area I'm going to chuck the whole thing back together.

Using ATF or appropriate motor oil to the correct level according to the overflow indicator hole, I trust.

I want to try & squeeze a new gasket around the crank area at the front of the case but am abandoning looking at the gearbox sprocket. I started this 'cos of the oil leaks & poor gear selection, the bottom line is that I need the bike to ride & not another project (I have 2 others that have been waiting a long time already..)

A quick question...
This is a 1961 bike (reg'd in '62) and according to the Draganfly catalogue uses 2 gaskets behind the crank end of the primary chaincase, one for other models. Anyone know if this is 2 together or one either side of the steel plate?  In my spare bits that came with the bike is a gasket for the crank end that is quite thick ( a bit like me !) , about 1mm , can I use this place of 2 thinner ones ??

I don't have my parts book with me, but it sounds like you're seeing a gasket and a metal spacer. This would be a good place for others to jump in.

Looking at part lists the "spacer" used at the rear seems to vary with year too. As it fits behind the frame, I presume this spacer goes between the frame & case (again the catalogue doesn't make this clear, showing at the nut end). There doesn't naturally seem to be a gap, should I force issues to create one by inserting a thin spacer??

I think this would be a small gap if you are missing the thick spacer between the front of the case and the crankcase. I have wondered why there was need for this spacer (chaincase to crankcase) in the first place and the only thing I have thought of is that BSA discovered that the cushnut hit the outer cover without it and they preferred to make a spacer rather than retool the die for the outer cover.
 

As usual any thought appreciated..

Cheers,
Adrian



Regards,

Richard L.
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: tombeau on 02.02. 2010 17:08
Hi,

It should be  possible to remove the splined shaft that the footrest attaches to with the chaincase still in place.It is a tube with a cam shaped disc on the bottom which has a peg on it, this locates in a hole and stops the tube from spinning around.
You should be able to loosen it from the frame quite easily, and with a bit of wiggling it will come out.

When I take the chaincase off my bike, I don't seperate the footrest from that shaft, I just wiggle the lot out in one go.

I think that you have to rotate the thing so that the tube is pointing downwards for it to clear everything, but to be honest I don't remember, play around it does come out of the gap between frame and chaincase.

Admittedly I dont have a fully enclosed chainguard (or any chainguard for that matter) but I wouldnt think that it would affect this.

Cheers,
Iain
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: trevinoz on 02.02. 2010 19:57
Adrian,
                As pointed out, you have to remove the rear chain to get the inner case off.
It takes a bit of juggling around the gearbox sprocket but will come off. there is no point in removing the sliding plate in situ.
The footpeg and splined shaft should be able to be pulled out and rotated as has already been stated previously.
I always put a gasket either side of the front steel spacer, usually you have to make your own.
If you are successful in removing the inner, make sure the footrest assembly is loosely in place before reassembling.
Perseverance will pay off.
Trev.
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: brackenfel on 03.02. 2010 18:23
Thanks to Richard, Iain & Trev...

I've been encouraged to persevere, for a while at least!
The gearbox was filled up to the level & so far looks ok.. Yes I do have the FERC diagram & it's a real monster in the flesh!!
I tried a bit of lateral thinking (probably not good at my age!) & moved the gearbox forward. Despite having dozens I couldn't find a spanner to fit the gearbox nuts so (may I be forgiven!) used a 20mm which was a snug fit! They were VERY tight !
I got the footrest mounting casting out & now know why getting the long spindle out initially was such a hassle - the splined tube is bent!!
Still can't get the damn casing off though.. The (enormous) sheet metal part of the fully enclosed chain is still an obstacle.
Now, I've looked in Haynes, the BSA owner booklet, Service Sheets, on the web, without luck.. Just how bad is rear chain removal as no-one seems willing to describe it!! More to the point, given the size of the front part of the FERC unit how the h*ll do you get the rear chain back on again??

I am getting there, the bike looks more naked by the day, the pile of bits on the garage floor gets ever bigger and the list of things to buy longer.. Oh dear, this is starting to look like another project....

Thanks.
Adrian
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: tombeau on 03.02. 2010 18:59
I have never looked closely at one of the se FERCs before, but looking at the drawing:

The back curve is held on by 2 bolts and captive nuts.
Remove that, spin the wheel until you can see the split pin, get that off and whip the chain off.

IT LOOKS LIKE the upper and lower sections are only held on by 2 bolts (and captive nuts ) per section. With those bolts off I would PRESUME you could drop out the bottom section and lift and wriggle out the top section.

I would GUESS that those sections are not bolted to the section that encloses the gearbox sprocket, as those sections of the chainguard have to rise and fall with the swinging arm,  so they probably just slide loosely over the gearbox sprocket section.
Somebody here must know if this is the case.

It looks like the section that encloses the gearbox sprocket is attached by a bolt to the threaded hole that is on the top of the primary chaincase, There seem also to be 2 holes either side of the sprocket hole.

Are the bolts for the sliding plate (on the inner chaincase) considerably longer on models with FERCs and do they go all the way through to the other side of the gearbox sprocket section of the FERC ?
This might have been explained already, I just havent read the post thoroughly enough

I would also GUESS that when refitting the chain, you do it with top and bottom sections off the bike and then refit them once the chain is on.

Now we know why this is such a rare part...a young guy with work tomorrow and a chisel!
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: brackenfel on 03.02. 2010 19:57
Hi Tombeau,
I've got the 3 easy bits off (had to remove the wheel to get the top section back out of the way.. The problem is the front section. The bolts from within the primary case by the slider are longer than the standard ones. Sadly the nuts are not (as far as I can see & from the parts lists) captive & getting around the back to hold them is impossible...

I can almost get the primary inner out with the front section still attached but not quite.. I need to be sure I can get the chain back on the front sprocket before I even consdier removing it.. It's nothing like a standard  case, it wraps right around the sprocket & extends back over the footrest shaft by at least 1" & is the same length top and bottom...

I too see why these are rare.. The bent  splined footrest holder has 2 chain grooves under the powder coat  so once upon a time either it was from another bike or someone fitted this damn FERC afterwards in place of a standard one..

Adrian
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: trevinoz on 03.02. 2010 19:57
It is common practice to leave the front section attached to the inner case off. I feel it will protect the inner case if the chain is thrown.
The FERC is simple to remove, just take out all bolts. two in the rear section and two each in the top and bottom.
Remove the chain and juggle the inner case off. It is a bit fiddly getting it around the sprocket but it is obviously possible or or wouldn't be there.
Replacing the chain is not easy. I feed a piece of approx 1.6mm steel wire around inside the enclosure and connect the chain to it and pull it through.
The gearbox nuts are 25/32" AF, one of BSA's oddities. Same size as the oil pump worm and lock nut.
Iain, you are correct in your assumptions. The front section bolts are long and go right through and the top and bottom sections of the chainguard do slide. Yes you do fit the chain with the chainguard off.
Trev.
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: tombeau on 03.02. 2010 20:19


I take it that you've tried getting at those nuts from underneath the bike and from where the back wheel used to be?
I would be starting to think about taking the heads off those bolts with a dremel. If it really is that awkward BSA must have issued a service sheet about it.
Iain
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: trevinoz on 03.02. 2010 20:20
Adrian,
            What you have is stock standard BSA parts, although the chainguard is optional.
Even if you had the one piece top run chainguard, you would still have the front section which is giving you so much grief.
The inner will come off with the section bolted to it, it has to.
Trev.
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: brackenfel on 06.02. 2010 16:44
Yippeeeee, success, the thing is off!!

Thanks to Trev & all who have posted & offered encouragement..
For future reference (and any other FERC owners!) you don't have to remove the FERC first, it comes off with the primary case. You do however have to take the chain off and move the gearbox well forward...

So, now all I need is some more time, some gaskets etc & some luck getting it all back together (the chain is going to have to be fitted after the cases!!)

One final question, on this thread at least . What is the little brass pipe hanging out the back of the crankcase (see photo below) I have a feeling it has maybe been contributing to the oil escaping. I intend to connect a pipe of some sort to it & find out :-



Many thanks again for all your help & encouragement. I hope as I get more familiar with the A10 I can help others along the way..

Cheers,
Adrian

Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: bsa-bill on 06.02. 2010 17:06
Hi Adrian
The brass tube is an mod fitted by a previous owner , it is pushed into the end of the breather circuit and would probably have a flexible pipe connected to it possibly routed to feed oil/oil vapour onto the rear chain .
I did this on my first A10 ( which was also 1961 - does it by any chance a welded bit at the bottom of the timing cover  *smiley4*)

All the best - Bill
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: Hubie on 07.02. 2010 07:35
Does anyone have a photo of the sliding seal?  I need to make up one as it appears part of mine is missing.

Thanks,

Hubie
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: flashblack on 07.02. 2010 08:02
Hi Hubie, and welcome, here`s a pic of one on e-bay:
  http://cgi.ebay.co.uk/NEW-CLUTCH-SLIDING-PLATE-BSA-A-B-MODELS-A7-A10-B31-B33_W0QQitemZ360220271324QQc  (http://cgi.ebay.co.uk/NEW-CLUTCH-SLIDING-PLATE-BSA-A-B-MODELS-A7-A10-B31-B33_W0QQitemZ360220271324QQc)

regards rich
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: Hubie on 07.02. 2010 08:54
Thanks for that Rich, I have the same on my bike, but there is a decent gap between the gearbox shaft  and the plate.  There is obviously some kind of washer/seal  or o ring that goes in there.  I am going to get some rubber sheeting and make up a seal to go behind the plate and in between the felt washer that is on the bike now to stop the ATF getting flung out of the primary.

It is either that or use chain lube instead.

Cheers,

Hubie.
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: flashblack on 07.02. 2010 09:00
Just a thought, is it definitely  coming out of there, or is it oil mist being blown out of the engine breather ?
  Rich
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: Hubie on 07.02. 2010 16:17
Definately coming out of there, nice red ATF!

Cheers

Hubie
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: trevinoz on 07.02. 2010 20:40
Hubie,
             The clutch centre hub should be a close fit to the sliding plate with almost no gap around it.
What clutch are you running?
If a six spring, there should be scrolled oil slinger pressed onto the gearbox end of the hub.
If a four spring, the slinger is machined into the hub.
Trev.
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: brackenfel on 07.02. 2010 20:46
Hi Bill,
Thanks for the advice about the breather mod.. Mine has engine / frame numbers from '61 , registered May '62 so I'm afraid it's probably a different one.
Got to get some gaskets, bolts (the long ones for the chaincase / FERC front are bent!!) & start putting it all back together..

Adrian
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: Hubie on 08.02. 2010 03:51
It appears then that the oil slinger is missing.  The bike is running a RGS clutch (4 spring) with the clutch hup doubling as the bearing surface for the rollers on the clutch basket.  If I can't find something to do the job, I will make something.

Cheers]

Hubie.
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: orabanda on 08.02. 2010 04:11
Contact Colin Tie (Perth WA); he makes and  / or modifies the backing plate and installs a seaql. It works much better.

9295 6875

(http://i302.photobucket.com/albums/nn82/orabanda/54A10primarydrivecasingfitted.jpg)

(http://i302.photobucket.com/albums/nn82/orabanda/54A10primarydrivecasinginstalled3.jpg)

Richard
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: orabanda on 08.02. 2010 04:15
This is how I added a pipe tp the breather hole, to prevent the crankcase oil / air making a mess at the rear of the crankcase.

(http://i302.photobucket.com/albums/nn82/orabanda/54A10enginebreather.jpg)

Mind you, the original arrangement ensures that the chain is always lubricated!
Richard
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: Hubie on 08.02. 2010 05:13
Thanks a million for that mate,

Now I know exactly what I need to get done.  Those picutres are a big help.

Cheers

Hubie.
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: bsa-bill on 08.02. 2010 11:01
I recall a trader (sorry can't remember who - was on Ebay) stating that the hub adaptor he was selling had the scroll the correct way unlike some others on the market.
So there are hub adaptors out there that are going to scroll oil out instead of in.

All the best - Bill
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: brackenfel on 08.02. 2010 14:41
Hi Richard,
Very neat, many thanks for the pics...

Adrian
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: trevinoz on 08.02. 2010 20:28
Hubie,
              The scrolled slinger should be a machined part of the hub, unlike the six spring type which has a pressed on part.

Richard,
              I like the seal but I guess the hub has to be machined off to accommodate it. Correct?
  Trev.
           
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: orabanda on 08.02. 2010 23:04
Trev,
Correct!
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: Brian on 08.02. 2010 23:48
This is a mod I have been thinking about for some time and its good to see how someone else has done it. I assume he has a bronze bush the other side of the seal.

My thought was to leave the clutch hub as it is except to machine the scroll off and use a larger seal to run on that surface, that would leave more room between the hub and gearbox sprocket to run the bush.

Must pull mine apart sometime and put some more thought into it.
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: orabanda on 09.02. 2010 00:23
Brian,
No bronze bush; it's a seal carrier.
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: Brian on 09.02. 2010 00:32
Hmmmmm, so if there is no bush what stops the seal from distorting when you adjust the primary chain. There would have to be something to pull the plate back when you adjust the chain. If the seal carrier runs on the shaft to do this then thats steel on steel, would wear a groove in the shaft.

I would love to see a picture of the other side of the plate.
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: trevinoz on 09.02. 2010 02:14
Brian,
            The plate is a sliding fit because the securing bolts have a shoulder which stops the plate locking solid to the inner case.
With the original set-up the bushed section of the plate finds its own centre when the gearbox is adjusted.
I suppose a garter seal would do the same.
Trev.
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: orabanda on 09.02. 2010 02:35
Trev described it well.
The plate will slide, and the seal retains its correct shape
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: Brian on 09.02. 2010 02:46
Thats the thing, the original design relies on the bush in the centre of the plate to slide the plate along when the gearbox is adjusted. I dont think a seal would tolerate that much pressure and would distort to the point of destruction. I think you would need a bush as well as the seal so the bush can take the pressure of moving the plate and leave the seal to do its job.

What I had in mind was to run the seal on the back of the clutch hub with a bush alongside running on the shaft, the bush being there purely to take the pressure and move the sliding plate during adjustment.

Richard, can you remember what the other side of the plate looked like, did the seal sit in a metal cup with a hole just large enough for the shaft to come through. If not then I am very surprised the seal will survive. If so then I dont like the idea of a steel carrier rubbing on the gearbox shaft.

Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: trevinoz on 09.02. 2010 02:52
Brian,
               I guess the proof is in the pudding.
Maybe Richard will let us know how many miles he has done on his modified set-up.
Personally, I don't have any problem with the original. I had better check to see if there is any oil in the chaincase.
  Trev.
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: Brian on 09.02. 2010 03:03
I dont have a big concern with the original design either and thats why I have thought about this mod but never got round to doing anything about it.

The only thing I do is make my own bush for the plate so its a neat fit on the clutch hub. I bought a new one for my 61' and it had more clearance than the worn out one !

I'm one of the ones that runs engine oil in the primary and while it does seep a little it certainly doesnt get to the point of dripping or making a big mess.

I've only got one swingarm A, the rest are plungers and now a rigid so its not a big problem for me.

Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: 1660bob on 09.02. 2010 17:11
Hi Adrian, just had a look at your dynamo drive pictures- Look Out!- that looks more like GORRILLASNOT!!!!!! *eek* *eek*
Regarding the spacer `twixt inner chaincase and frame (47-4792), I have only found one parts supplier who lists it  and that`s Draganfly- but they cross reference it as a 5/16 plain washer!!!!!- I suspect the "gap" twixt case/frame will vary bike to bike, hence it may be washers as required, or perhaps none at all-certainly the gap on my bike initially looks to be between nothing and one washer here. Perhps BSA were somewhat grandly describing it as a spacer, when all it ever was, was a washer or two!
My advice would be thus: assuming engine crankcase is correctly bolted in, all faces clean and undamaged and nothing distorted,the spacer plate 42-7518 should be sandwiched between two gaskets (42-7509), and the inner case placed over them onto the crankcase spigot and bolted up using the two bolts 42-7516, AND all three forward  screws 42-7517(?) using suitable spacers  to mimic the outer chaincase cover.This will prevent any tendency for the inner case to tilt, and should, when all nipped up, leave the inner ch/case in its natural position.You should now be able to see the true gap between bottom rear end of casing/frame plate for "shimming" with washers as req. Correctly done, you should be able to tighten the bolt 64-6054 without straining or distorting the case.Thats how I see it, but I`m new to this so if anybody knows better,shout up!! HTH, Bob.
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: brackenfel on 09.02. 2010 18:51
Thanks Bob,
Sounds like excellent advice to me & once I've sourced the necessary gaskets etc (and it warms up more than a bit!!) I'll make a start.. Thanks for the tip about the spacer, I'm sure production tolerances for frames meant that there's a good variety out there!   I'll get some more suitable grease for the dynamo chain as well, not too many gorillas around here I'm afraid..!!

Cheers,
Adrian
Title: Re: Problems Removing A10 Primary Chaincase Inner
Post by: Hubie on 15.02. 2010 02:30
Hi all,

Finally got the primary apart last night and fashioned a seal out of rubber sheeting and fitted it up.  Not a drip of ATF from the primary now after a decent 60mph run.  All is good!

Cheers

Hubie