XBAPH parts

[Vincent Brake]

Hi, I was bussy to give mi series A single a good service and did check (as it aint broken yet) the gearbox, (jumping out of gear now and again) and see the 2 gears on the main axle have bad worn dogs in them, so has the double gear as well.

not available on the VOC spares Co. as i can see.

now who can help me there??

main sprocket gear PR50-15BA has 33 teeth the sigle on the timing side 30 and the double sliding gear has 26x 20 teeth

cheers

 

[greg brillus]

Contact Draganfly.

 

[Vincent Brake]

thanx Greg

 

[greg brillus]

Another small trick I do on these and the post war boxes is to fit a small shim say 0.030" between the output shaft (sprocket shaft) and the output main bearing. This moves the output shaft slightly to the right allowing a better engagement of top gear, though not too much as you don't want the teeth to hit the layshaft second gear teeth. These boxes are pretty much the same as the pre war Ariel Red Hunter's and others except for the mainshafts which differ where the clutch is mounted. I recently had one of the Ariel type shafts modified to suit the series "A" pattern, worked well but not easy on a hardened shaft.

 

[Vincent Brake]

i thought of that, but than one has to grind the wear and tear, a bit onwards with a diamond, and they were very thin allready so only way is new.... or best used ones.
but i will sure do this on the ones i get.
thnx
also heard a post W cluster might fit as well, so i take one apart,

 

[Robert Watson]

When I was doing my two A gearboxes and needed parts - which were not available at the time, I bought a decent used post war Sq4 box. Pretty much all the internals are interchangeable.

 

[Nulli Secundus]

When I was doing my two A gearboxes and needed parts - which were not available at the time, I bought a decent used post war Sq4 box. Pretty much all the internals are interchangeable.

I would wager that an Ariel Square Four would give the gearbox a fairly easy time with only 250cc punching at a time.

 

[Robert Watson]

I am sure that almost any other bike fitted wit a BA or BAP box would give it an easier time than a 1 litre V twin BUT that really is irrelevant as the internals are the same as what Vincent used, and as I understand it the early A twins could destroy a gearbox if the clutch hooked up and that sometime later they improved the quality of the steel in the gears, so a post war Ariel box in theory should be stronger that a Pre war A box.

 

[greg brillus]

Having now worked on both post and pre war twins and especially the new ones built by Neal and Rodney, it is amazing the Burman gearbox can cope at all when you compare the size of the gears/shafts. I think the near inability of the cork insert clutch to handle the torque might be a savior. The dry clutches on the new ones is fabulous, gearshifts like a Jap box with no crunching into gear.

 

[davidd]

I did mention to Vincent that I thought the pre-war and post-war clusters were interchangeable. Carleton and I run pre-war close ratio clusters in a post-war box. I thought he might have a post-way box and he said he did.

We found that the problem was the giant bearing that left no meat between the two bearing pockets. The shells were usually cracked between the bearings.

David