Wanted to complete restoration.

[John Wakefield]

I guess that is what I may end up doing John, I just preferred the rear wheel route. Regards Les.

Frankly I would go for the 2T gearbox option, its a far better engineered set up as the drive gears are fully lubricated, as long as you have the standard secondary drive gearing (18T gearbox and 48T final drive sprockets) the speedo should read right. I can never understand why Bert Greeves went for a seperate hub drive on roadster twins when the drive was in place on the 2T 3T and 4T engines, as he was known to be a penny pincher he could have save a few bob by not having to buy in the angle hub drives. If the cable breaks on my bike I will certainly replace it with the shorter one to gearbox, and remove the hub gear. This also makes it easier when removing back wheel as cable does not need to be disconnected.

[IanCordes]

The number you want Les is BG2504/01, the same as on the alloy hub, as Tony already mentioned. It is the same on them all, tin, finned or alloy fwh. John W mentions the fwh has a longer thread, which is incorrect. They are all the same, clockwise drive, short thread.

I would agree with JW though that the gearbox drive is stronger, and you can buy them cheap as chips compared with the right-angle drives.

Ian C

[John Wakefield]

The number you want Les is BG2504/01, the same as on the alloy hub, as Tony already mentioned. It is the same on them all, tin, finned or alloy fwh. John W mentions the fwh has a longer thread, which is incorrect. They are all the same, clockwise drive, short thread.

I would agree with JW though that the gearbox drive is stronger, and you can buy them cheap as chips compared with the right-angle drives.

Ian C

Ian I think you are referring to the gearbox drive for the 9E 32A etc which is bolted onto bottom of the gearbox. The drive on the twins is fully built in. (see items 90 to 93 in this diagram http://www.villiers.info/picpop.php?part=TGG024 )

You are also wrong in thinking that all the angle drives were short thread. Not so as the attached diagram shows. Short 1.170 and Long 1.687. The short one fits tin hub and long one alloy hub

[IanCordes]

Fair enough regarding the gearbox drives John. I only have singles, and thought twins were the same.

I am not wrong about the right-angle drives on hubs fitted to Greeves; you are! Your attachment does not refer specifically to Greeves, but all makes and models which use the right-angle drives. Check your parts books. All models, from the 1959 TA to the 1965 TFS, and all roadster models of the similar period, all list M/WBB105 as the speedo drive, irrespective of whether their hubs are tin, finned or full-width alloy; fact. The 1959 parts book qualifies that as being BG2504/01. I have had an alloy hub in a loose wheel in my hands this morning, and have fitted a BG2504/01 to it, which is correct, as Tony earlier confirmed in this thread. In fact, if you wind the drive too far into the hub, the 14T driven pinion will go beyond the 44T driving gear in the hub, missing it completely! It is important to set them in to the correct depth, so the gears fully engage each other. I have seen several 44T gears with 1/2 their threads stripped off, because they were not correctly aligned.

So please do not advise anyone on here that they need the long thread drive for their FW hub, they need BG2504/01!

Ian C

[John Wakefield]

I see no reason why the longer drive cannot be used as long as it is adjusted to mesh correctly with the large hub gear.

[IanCordes]

Don't try and dig yourself out of ! It would stick out of the hub too far, alter the cable run, and on a trials bike, be more likely to get damaged. Why fit the wrong one when you can fit the right one? What I am saying, John, is that the correct one is BG2504/01, not the long-thread one, as you asserted; end of story. I am not getting into what if this, what if that... You could go one forever.

Ian C

[John Wakefield]

Yes but correct ones are not available, on a road bike it wont matter if it sticks out a bit. Les is doing a Road bike. In any case a long one can be shortened by turning a bit off the threaded section and cutting back the spindle to suit then re drilling the split pin hole.

[IanCordes]

You could do that, John, it's true, although you may have fun drilling a hole through the hardened steel shaft for the split pin. First of all Les has to find a long one, which from what I have seen are as plentiful as the short ones. Also, I have seen long ones going for over £200 on fleabay. Remember these were fitted to a myriad of makes going back to, and before the war, including Vincents etc; often driven off the front wheel.

Then he has to ensure the body is not upside down and pointing the wrong way like Tony's. Then he has to ensure it has clockwise rotation, Then he has to ensure the internal gearing is correct. The numbering on the end plate indicates specification. Only then can he start chopping it up as you suggest.

But, fair play, it could be done.

Ian C

[John Wakefield]

Or just buy a shorter cable for around a tenner, connect to existing gearbox drive and job done.

[Colin Sparrow]

I have got a gearbox drive unit you can have if you want it, Les. Goodness knows which engine type it's off, though.

[350biker]

Les - have you spoken to Colin East at East Restorations about a gearbox? He restored the one for my Scottish a year or so back.

[mayfield]

I tried Colin East but got no answer, perhaps on holiday. Thanks for response.