The BSA A7-A10 Forum
Technical (Descriptive Topic Titles - Stay on Topic) => Gearbox, Clutch, Primary => Topic started by: jachenbach on 20.11. 2015 00:56
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Sorry if this has been done before, but I've tried searching the forum and the internet to no avail. Suzuki GS550 clutches are cheap and readily available. What I haven't found is details on how to go about fitting it to the A10. The Pearson conversion is 525 pounds plus shipping. I can buy a complete used Suzuki clutch for $40-50 US. As I need 2 of them this is potentially a huge savings. Can someone direct me to the details on what is involved to machine and install it?
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These links may help
http://www.a7a10.net/forum/index.php/topic,3538.0.html
http://www.a7a10.net/forum/index.php/topic,3152.0.html
S
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The Pearson conversion is 525 pounds plus shipping. I can buy a complete used Suzuki clutch for $40-50 US.
...or a couple of complete used Suzukis for the price of the Pearson clutch. (No knock on the Pearson, it's probably great.)
Richard L.
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It is Richard! I took a deep breath and bought one a couple of years ago and have never regretted it. Admittedly my old clutch was a bit past it but fitting the Pearson one transformed the bike.....it felt like I'd fitted a new gearbox too! Much lighter to use, never slips, nicer feel to the gearchange and never a problem finding neutral. The price has gone up quite a bit I know but I could see there was a lot of work in it, as far as I recall the outer basket was his own manufacture, all the parts were new and it came with a nicely made sliding plate with oil seal.....
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Thanks to Orabanda I've just installed & now running a Suzuki GS550 ...
I dont know why the hell I ever persisted trying to get the BSA 6 spring operational..
I took bike out for a run today & can report every thing is working perfectly,
I can even select neutral with the motor running.. *eek*
I'm VERY happy with mine.. out with the old... in with the new..
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Wozza is that a commercial conversion kit or did you knock it up yourself? Certainly looks the business *smile*
After pulling the clutch on my project '62 Super Rocket I'm pretty much inclined to go the Suzuki path myself.
Initial issue was fairly obvious
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G'day oldvet... *eek* it's a Colin Tie built clutch, Orabanda, ( Richard )
was going to build me one much the same, but due to work commitments etc,
& rather than hold me up decided to send me one of his..
Just in time for Christmas.. *smile*
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HI Oldvet,
Obviously something very out of line or other major issue going on there???
Were you trying to run a dry primary?
Or a chainwheel made of cheese??
No matter which clutch you replace it with you need to resolve the underlying problem??
John
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mate fitted same to his 500 goldie for classic racing never been a problem
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I have one almost identical to Wozza's and the mainchallenge with the conversion was fabricating a centre.
Depending upon whether you have a tapered main shaft or the splined type, this will vary and acts as the bearing carrier and locates the alloy plate centre.
My engineer made a tapered centre and unfortunately as its all assembled I cannot readily post an image. (I'll check my stored images just in case)
I initially fitted a dural sprocket but that did wear far faster than I wanted (running dry admittedly) so I went back to steel and moved it onto a wet/road machine.
The 550 clutch runs a decent basket bearing and the top hat bearing. We did reduce the height of the basket and refitted the steel supporting ring. Clutches do work better when they have teeth for the chain to run on.
The Suzie conversion is a good option for a wet road clutch and I recall we have had threads on people going down the belt path with them too.
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famous last words "my clutch is all assembled"; removed the primary this afternoon to get the swing arm out so took some pictures of the centre we did for my suzuki clutch. Not a pearson or anything fancy, just a local engineer, externally it looks like the other images, top hat bearing, retains steel ring etc
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This is really interesting to all of us I am sure. A phil pearson would be almost $900.00 with shipping for me. I called a local breaker, he quoted me $15-$20 dollars for a gs 550 clutch. They are not rare, or a hot commodity at all over here.
Is anyone in the process of converting one of these right now, or has one they could take specific measures off of? I am really thinking about giving this a shot, I have access to the equipment needed, and a desire to save $700+ dollars. *eek*
Lee
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HI Oldvet,
Obviously something very out of line or other major issue going on there???
Were you trying to run a dry primary?
Or a chainwheel made of cheese??
No matter which clutch you replace it with you need to resolve the underlying problem??
John
John this is how it was when I bought it. Alignment not the issue, chain tension was the problem. The previous rider had no clue and just laid it up when all went pear shaped. Consequently I now have a very low miles bike and restoration is underway. I've attached a pic of the bike as it was when purchased.
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Thanks for the comments and added info fellas, much appreciated.
There is now a lot happening with the restoration seeing as I gave it a real boost along over the Christmas break. Blasted the frame and heavy metal bits, gave it a 2 pak paint job and spent lots of time plating all the zinc bits.
Hubs are refurbished and currently being laced into flanged Akronts with SS spokes. Tank is now in chrome and handed to my painter along with Oil tank and tool box for paint.
Magneto & Dyno restored and nice box of parts arrived from Beesamac and some from SRM. Instruments refurbished beautifully by David Woods. Just waiting for my paid workflow to slow so I can slot the engine and trans into the queue for a rebuild.
I think I might be a bit optimistic hoping for completion by the All British Rally in April though :(
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I see this metod being used all the time and wonder why people do it.
If you troll the pages of this forum you will find countless numbers of owners who have needd to pull their freshly rebuilt engine &/or box out of the freshly restored frame one time too many resulting in lots of damage to the nice new paint work.
Always best to sort out the engine & box befofe you think of touching any frame part ( brakes excluded ). Put up a thousand or two miles on it to prove its reliability then pull down & do the cosmetics.
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Hi All,
Theres a post on the Britbike forum by Andy Higham who is building a hotted up BSA B31 and fittng a Suzuki clutch
I like the method he has used to get the Suzuki inner drum to fit the BSA shaft adaptor *bright idea*
It will add a little weight but will be much stronger than having splines in the ally
http://www.britbike.com/forums/ubbthreads.php?ubb=showflat&Number=641070&#Post641070
Cheers
John
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Thats a nice job he's done and quite clear.
What he hasnt done (yet?) is machined down the basket as they are very tall and wont fit inside standard primary covers. He has also removed the strengthening steel band that supports the basket at its weakest. Personally i wouldnt do that.
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That's an excellent idea for mounting inner basket. Now who has a rusty old 4 spring basket they would part with??
I will try and get some more pictures up.
I know there is a thousand ways to do this, if my way works out I will post some detailed pics and measurements so everyone at least has an idea of what they need and what's involved if they decide to go this way.
Lee
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Speaking of baskets that fit the a10 four spring adaptor, are there any others? Like a 3 spring or a65 etc?
I am just going to cut the adaptor out of it anyway, I just need one that fits.
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In my case I didnt have anything other than 6 spring parts, but if you do then the 3 or 4 spring parts look like a good option
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RR,
Are the adaptor splines for the four spring and six spring the same? If so, I have a couple 6 spring baskets that are in rough shape and OK to use as donors.
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Hi,
The A65 and Triumph clutch inner baskets are built up and have a shock absorber inbuit
The splined centre has 3 or 4 legs that fit between the rubber buffers in the unit
I cant see how these could be used, unless a flange is welded on ???
The 6 spring inner only has a very narrow width on the splines, so not a good piece of engineering
Heres a link to a solid type (rusty)
http://www.ebay.co.uk/itm/Triumph-Pre-Unit-Clutch-Centre-also-Tiger-70-80-3H-3HW-New-Old-Stock-T417-/262300423104?hash=item3d1252d3c0:g:pBQAAOSwll1WyWnR
John
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As John mentions the 6 spring parts are not much use in a conversion, hence why I went down a bespoke road.
I'm happy with my non std centre and the direct application to alloy as a one off build
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Guys,
Do you have to shorten the inner clutch basket because stock uses 6 disks, and now we are using 5? It "looks" like nothing needs to be done here, but I want to make sure as this is the time its easy to modify.
Its a good thing I dont have to pay myself a labor rate, thats for sure. And with every part being a one-off, I hope nothing ever goes wrong with it either! *conf*
Lee
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Guys,
Do you have to shorten the inner clutch basket because stock uses 6 disks, and now we are using 5? It "looks" like nothing needs to be done here, but I want to make sure as this is the time its easy to modify.
Its a good thing I dont have to pay myself a labor rate, thats for sure. And with every part being a one-off, I hope nothing ever goes wrong with it either! *conf*
Lee
Mines' back in the bike so I cannot recall how many plates I used; but the inner plate carrier was unchanged.
It was only the outer basket we removed the steel ring from and shortened, then refitted the steel ring.
I don't have massive clearance between the clutch and the outer case, but there is clearance.
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Thanks RR,
I shortened the outer basket and re-used the steel support ring, the inner looks ok,. My concern was if I will get enough spring/ clamping pressure against the frictions so I don't have slip when I remove a plate.
Lee
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Lee,
with my basket machined enough to clear the outer cover, I recall when I initially reassembled; the plates were not under any pressure and even rattled, so I had to get an extra plate. Once I had contact between the end plate and the basket inner through the plates I was fine. But I can't tell you readily how many plates that resulted in.
Just that in my case I didnt need to modify the inner at all. If I wanted to reduce the number of plates from the number I ended up with something would have had to be changed.
In my case it was very clear it wouldnt work as initially assembled and fitting a further plate was the easiest option.
There was certainly no middle point where the spring tension came into play.
The (6) sprung bolts on mine are done up tight, unlike a typical british clutch where tension is variable with a nut on a stud.
Sounds like you need to mock assemble. As mine's in the bike I'm not readily able to confirm heights or plate numbers.
Tim
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It's getting close to a bit of assembly, but not quite yet.
Once I get mounting the inner basket done and everything looks good I am going to post some pics.
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OK, outer basket is done. I made a sleeve to hold the bearing, which is backed up by a snap ring. The bearing is an R22. Thanks to Mr. Greybeard, I got a sprocket, that and the outer basket were both press fits onto the sleeve. The three reduced height socket head cap screws bolt them together. The bearing is a press fit into the sleeve.
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Pictures again, maybe..
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For the inside, I turned a shallow bearing stop, drilled and tapped for counter sunk screws. These go all the way through to the back side of the bearing sleeve. It sandwiches everything together.
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Then I worked on the inner basket. I bought a new 4 spring cast iron basket and then carved it up. *eek* I reduced the thickness of the Suzuki basket, and the opened up the backside so the cast iron disk was a .003 thousands interference fit, heated the aluminum and pressed in the cast iron. I also reduced the boss in height on the inside for a custom nut I have yet to make (no stock).
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After I installed the iron disk, I found I had to relieve a small amount from the aluminum so the adaptor didn't interfere. Did that, spot faced six spots inside the basket and bolted it together with some locktight. Also chance had it that to holes in the disk and aluminum lined up so I taped those and used set screws and locktight in those also. I am happy with everything to this point, now I need to make a custom nut and lock washer. I am still on the fence about cutting the adaptor off for an inner case oil seal, but we will see. Also, could anyone explain to me how the pressure plate roller lift was handled on one of these conversions?
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Hi coater,
Only yesterday I was wondering how you were getting on with the conversion *????*
I bought a s/h 4 spring inner drum yesterday on ebay to chop up for the conversion
Today when working on an A10 I found the inner drum needed replacing but it would have been ok for use on the conversion *sad2*
could anyone explain to me how the pressure plate roller lift was handled on one of these conversions?
The suzuki pusher spindle is turned down to 1/4in and the original BSA pushrod shortened to accomodate the difference
the pic attached should show the modified pusher
On your conversion will the pressure plate clear the allen bolt heads at the bottom of the inner drum?
John
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Hi John,
I used reduced height allen heads, you have to look around a little to find them but they are out there. After everything is together, I have .036 clearance between the pressure plate and those allens.
The inside of the cast iron inner hub is the boss that goes against the bearing race. So basically after you cut the disk out of the cast iron inner, the disk is backwards to how it would normally be. That boss is long enough to get you above the fasteners without having to use any kind of spacers.
I just ordered some hexagon stock to make the nut with, after that is made hopefully the clutch is done.
My only concern now is the thickness of the entire clutch assembly. It would be a real bummer if it interfered with the primary cover, but without a way to check it I am just going to have to hope its ok.
Lee
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John,
I now see what you mean, you are talking about the Allen heads inside the inner basket! And yes, they do interfere with the pressure plate. I am changing them out right now for socket head set screws. Those are only for shear ( stop the cast iron from spinning in the aluminum basket) and set screws will act exactly the same as the Allen's, but will be low enough not to interfere.
Thank you for spotting that! It's much, much easier to fix it now than find out once it's on the bike!! *smile*
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hi guys, I seem to have one of these baskets that I have no use for so, cheers
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there you go friend, that was the single largest expense I had building the clutch- and you already have one! *smile*
Other than that, a sprocket, a cheap suzi clutch, a bearing, and some hardware (thats in order of cost also).
The really hard part was figuring out the first one.
I like the way I did mine, but of coarse it could be done many ways.
I can take more pictures or exact measures of the way I did it, and someone could take it from there to either copy or modify as
they see fit. But at least they will have a road map to follow if they choose.
Lee
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OK,
When I fitted my clutch and set the chains, I could see a quite noticeable wobble in the whole thing. I have limited tooling for machining here at the house, but I cobbled together enough stuff to place an indicator on and found the main shaft bent.
Ordered a new shaft from DeGroot. Very nicely done that, the nicest reproduction part I have ever received from the British parts market by far. Polished kick start side for bearing fit and fitted straight away.
Now ran into the problem of outer basket and pressure plate fouling the primary cover. Not a lot, but you can see the shiny witness marks inside the outer cover.
Seeing its a tight squeeze to fit this thing in the first place- I imagine every clutch, bike, and primary case difference is going to matter when it comes right down to it.
So: if your frame is tweaked, if your main shaft sticks out slightly more, if your primary cover has been glassed aggressively a few times, if your clutch adaptor sits slightly more proud than the next bikes, etc etc. you may have the same problems.
I could modify my inner cover and add a spacer at the crank snout. I could cut a 1/4 inch spacer and polish this to fit between the inner and outer. I could look into tweaking the gearbox mounts and adjusting drive chain alignment, or I can do some additional measuring and try to thin the clutch down one set of plates- which is exactly what I am going to look into.
My inner cover is NOS, and way too nice to butcher.
So thats where we are at right now, I am going to try to thin the inner and outer baskets and hopefully everything will work out.
Lee
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Take one fibre and steel plate out, and machine down the outer basket accordingly.
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Unless I missed something, how about an extra spacer/shim behind the inner cover at the Crank end?
Been a while since I played with a Swing Arm model though
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I could modify my inner cover and add a spacer at the crank snout.
Lee
Dutch,
You missed. ;)
As far as removing 2 plates, when I do that I don't have any pressure plate pressure.
All these parts are used, and I think my frictions are well worn.
I have not measured anything, but is it possible to shorten the inner basket without making the pressure plate bottom out on the spring perches?
Lee
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If someone who uses one of these clutches, or someone who has owned a few Japanese bikes had to guess:
How much clearance do I need for full pressure plate lift? If I have my measurements correct right now, I have between 65 and 70 thousandths before I rub on the outer cover.
I am finding this measurement very hard to make with any accuracy at all. *sad2*
So if a good guess is made, what do we say? 100 thousandths, 200, 300?
Whatever I do to get this clutch to work, I am going to have to modify an inner cover. There is only so much I can take off the thickness of the ear that mounts by the foot rest.
Lee
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Hi Lee,
You need to "lower" the inner basket; it is sitting too high on the cast iron splined adaptor.
Send me a personal message including your email address & I will send you a swag of pics how my arrangement differs to yours.
Richard
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Lee, did I miss something else? *conf*...anyway, I measured the 'lift' at the end of the push- rod to be about 1/8" (~3.2mm-ish)....simply by using the depth gauge thingy on the end of my sliding ( digital) caliper on the end of the mainshaft/pushrod, and activating the hand lever.... *dunno*
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I didn't make my Suzuki clutch. I bought the last one of a batch that Colin Tie had for sale. I had to get a spacer made in between inner and outer primary cover. I hope this picture is small enough to upload. The Watercutting Company did it for me. It cost NZ$100. He still has the drawing - if this is a help to anyone. I had to get longer Allen screws and make a spacer for behind the footrest mount, to the back plate.
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hi guys, nice job that, cheers