Jack Knight Transfer Gears

Ive got a set of 1.08 transfer gears and I think I may be missing some parts. I got them in a job lot of spares. 

I think i'm missing some bits and I have some general questions. 

There was supposed to be some sort of through bolt with a flange that hold its all together but i seem to be missing that. There is also a small ring that appears to fit between the two roller bearings, but when you put that in the centre of the assembly it stops you applying any preload as it stops the two bearing being pressed together. Im not sure of the purpose of this, or have I got it set up wrong ?

Does anyone have any information on the missing parts or how to set these gears up ?

Most of it looks to be there, it is missing the End Washer and Bolt though.

The parts fit over the shaft as you have them laid out, over the Shaft it's :- Bearing, Spacer, Idler Gear, Bearing, Collar, End Washer and then Bolt.

The Spacer is as you have surmised, to apply the correct pre-load to the Bearings so they can't be over tightened, much in the same way as our Front Wheel Bearing assembly.

Fitted in the the Gearbox, the Bolt goes in to the Gearbox side, but you need to be sure it doesn't poke through the Idler Gear (Bearing) hole in to the inside of the Casing, as the Web of the Crank swings around past that. It can poke out a little, but check there is clearance to the Crank Web - I'd suggest a minimum of 0.030" here.

The Bolt is an Inhex Cap Head from memory.

okay, but with the spacer between the bearing, I can not get any pre load at all. The gear just rattles around on the bearings, so im stumped ?

I have these photos I down loaded from eBay some time ago. So not mine but shows something very simillar to yours.

It does look like you might be missing the part that goes in the gearbox with the threaded hole for the bolt. First 2 photos.

 12A1288-3-Sync-Straight-Cut-001.jpg   58.59K   1 downloads  12A1288-3-Sync-Straight-Cut-002.jpg   76.72K   1 downloads

 12A1288-3-Sync-Straight-Cut-003.jpg   48.49K   2 downloads  12A1288-3-Sync-Straight-Cut-004.jpg   45.87K   1 downloads

okay, but with the spacer between the bearing, I can not get any pre load at all. The gear just rattles around on the bearings, so im stumped ?

They did have several incarnations of these, I suspect yours maybe earlier than the one I had.

The Washer * maybe * a side spacer fitted between the Gearbox Case and the Bearing on that side. I'm not sure then how you maintain the pre-load, I guess it must just be on the bolt with some thread locker ?

yes im starting to think it might be a spacer that goes on one side of the bearing. Ill have to try and mock it up and see. 

 

okay, but with the spacer between the bearing, I can not get any pre load at all. The gear just rattles around on the bearings, so im stumped ?

 

They did have several incarnations of these, I suspect yours maybe earlier than the one I had.

The Washer * maybe * a side spacer fitted between the Gearbox Case and the Bearing on that side. I'm not sure then how you maintain the pre-load, I guess it must just be on the bolt with some thread locker ?

 

Thats a great help thanks you. I can kind of see what im missing now. I do have a screw cutting lathe at home so its not beyond the realms of possibility to manufacture the missing part. 

I have these photos I down loaded from eBay some time ago. So not mine but shows something very simillar to yours.

It does look like you might be missing the part that goes in the gearbox with the threaded hole for the bolt. First 2 photos.

12A1288-3-Sync-Straight-Cut-001.jpg 12A1288-3-Sync-Straight-Cut-002.jpg

12A1288-3-Sync-Straight-Cut-003.jpg 12A1288-3-Sync-Straight-Cut-004.jpg