Looking for someone to build up my gearbox

[Robin]

Hi Folks,

 I'm looking for some advice. I'm currently building up a Greeves special and need a gearbox. Greeves boxes are impossible to find and I'm currently looking at fitting an A7 A10 plunger gearbox. These have been used successfully before on Greeves bikes. This picture shows a Greeves racing machine  with the plunger box fitted.

I have a complete A7 box that I purchased. I've taken it apart to clean and check all the components. Putting it back together I'm afraid has me beat. It needs someone more expert than me!

Is there anyone commercial or private, that I can send the gear box to and have them build it up for me?

Thanks,
Robin.

http://i.ebayimg.com/00/s/MTIwMFgxNjAw/z/8W4AAOSweW5VEztB/$_57.JPG

[muskrat]

G'day Robin. 
That's an interesting set up. I've always hankered for a Greeves chook chaser.
The bolt up boxes (rigid/plunger) are a good sturdy box. Gear selection can be a bit iffy if not set up right.
Find an exploded picture of the box here http://www.a7a10.net/forum/index.php?topic=3303.0  more info here http://www.bsawiki.co.uk/chaps/10-transmission/17-chapter09
I'm sure a UK member will chime in with help soon.
Cheers 

[duTch]

 Hiya Robin- they're fairly simple and easy to do, assuming the bushes are in good shape...just a couple of things to note;

 I find it sometimes helps to slide the selector shaft in straight after adding the layshaft, it holds that fork in place- push it through so it comes out the other side so the other fork can go in, personal choice..

 And VERY IMPORTANT, is the thrust washer BEHIND layshaft 1st gear, and its buddy,sliding spline gear [also known as (H)and(F)- but not the H and F on the diagram in Muskys wiki-link].

 This thrust washer MUST be inboard with the chamfer on the ID against the spline (allows it to butt up better)

  If that T-washer is in the wrong place, it's likely to bust teeth- I haven't done it to that extent, but have evidence of a case that did...

   good luck

[RichardL]

Well, Dutch, I believe you have put the exclamation point on why Robin is confounded. As for myself, I have done one A10 gearbox rebuild. It was guided by the Haynes maual and is working, in my opinion nearly perfectly. As for mechanics who can do it for you, being in Chicago, my local knowledge for the UK is limited. SRM Engineering in Aberystwyth, Wales would be the big player. The other one I like to promote is Leigh Classics in Leigh-On-Sea. This is strictly bias from having visited the shop when I was doing some work in London. I was a stranger well-received and, I feel, befriended. Aside from that, Andy is a kick-ass mechanic who services BSA and other brands as well as building beautiful Rocket Gold Star replicas. If you end up at either of these places, please offer my regards and tell them Richard from Chicago sent you. They will know who you're talking about. Hmmm, who knows what I'll get out of it? Nothing but good will, I'm sure.

Richard L.

[Dean]

Hi Robin
where in the UK are you?

[Robin]

Thanks that link on assembly has been helpful. I've done a couple of dry runs based on that but still have a few issues.

Not knowing the box. I'm not sure where 1st gear position is and what position the claw  that moves the camplate should be.

How do you hold the camplate in postion while sliding the assembly into the casing?

Thanks,

Robin

 Hiya Robin- they're fairly simple and easy to do, assuming the bushes are in good shape...just a couple of things to note;

 I find it sometimes helps to slide the selector shaft in straight after adding the layshaft, it holds that fork in place- push it through so it comes out the other side so the other fork can go in, personal choice..

 And VERY IMPORTANT, is the thrust washer BEHIND layshaft 1st gear, and its buddy,sliding spline gear [also known as (H)and(F)- but not the H and F on the diagram in Muskys wiki-link].

 This thrust washer MUST be inboard with the chamfer on the ID against the spline (allows it to butt up better)

  If that T-washer is in the wrong place, it's likely to bust teeth- I haven't done it to that extent, but have evidence of a case that did...

   good luck

[Robin]

That sounds like a good idea!

Thrust washer chamfer postion duly noted.

Thanks,
Robin.

 Hiya Robin- they're fairly simple and easy to do, assuming the bushes are in good shape...just a couple of things to note;

I find it sometimes helps to slide the selector shaft in straight after adding the layshaft, it holds that fork in place- push it through so it comes out the other side so the other fork can go in, personal choice..

 And VERY IMPORTANT, is the thrust washer BEHIND layshaft 1st gear, and its buddy,sliding spline gear [also known as (H)and(F)- but not the H and F on the diagram in Muskys wiki-link].

 This thrust washer MUST be inboard with the chamfer on the ID against the spline (allows it to butt up better)

  If that T-washer is in the wrong place, it's likely to bust teeth- I haven't done it to that extent, but have evidence of a case that did...

   good luck

[Robin]

Hi Dean,

I'm near Edinburgh. Scotland.


Robin.

[chaterlea25]

HI Robin,
Would Rob Wardley in Newcastle?(I think) be acessable to you?
He is a forum member and works on BSA's
I'm a lot further away in the South of Ireland,  but if all else fails ???

HTH
John

[Robin]

Hi John,

Thanks for that. I'm making some progress thanks to the input already given. I think now I can with some luck do this myself now.

Am I correct in assuming this is the nuetral position?

Rob.

[duTch]

Well, Dutch, I believe you have put the exclamation point on why Robin is confounded.

... Not quite sure what you mean there Richard...?

  Robin

I'm not sure where 1st gear position is and what position the claw  that moves the camplate should be.

How do you hold the camplate in postion while sliding the assembly into the casing?

 I lay the box on the side with the camplate at the bottom.  The camplate has four large 'scallops' and one small one, which is neutral. First gear position is the only scallop on one side. Locate the camplate plunger (that's the thing with the spring inside) in neutral scallop but only just so it stops the camplate from flapping 'round.

  When installing the inner cover, you only need to get 'The Claw' inside the ballpark and it fairly much sorts itself out, but you also may need to take into account the thickness of the gasket you use- this can affect layshaft end-float, and/or (dis)engagement of 'The Claw'...

  Hope that makes some sense...?

[Robin]

Sorry I'm confused. Are you saying to fit the camplate into the shell first?

[duTch]

 yup- no way of getting it in later

[Robin]

Got it thanks. That had me puzzled - Of course it can't!

Vertical drive side down casing resting on a tin can. Camplate loosely fitted to the shell - plunger on the nuetral dimple. Then Large mainshaft pinion in loose first. Lay shaft in next with fork. Last cog left off. Mainshaft in with fork and then the rest just follows.

Easy when you know how! Wow! I feel like I've been in a battle that won the war!

Thanks guys.

[RichardL]

Well, Dutch, I believe you have put the exclamation point on why Robin is confounded.
 

...

 Not quite sure what you mean there Richard.

Dutch,

Robin was asking where to send it, not how to do it. You gave him a useful fine point that would be encountered somewhere in the middle of assembly, but it wasn't yet established that he knew where to begin the assembly, or even wanted to. Obviously, Robin is going for it (good on you, Robin) and I am predicting success with the good advice he is getting.

Richard L.