I’m trying to put my 1950 Flying Squirrel (distributor model) back on the road and am having problems adjusting the primary chain. The gear box only has around 1/4″ of adjustment due to the back of the gearbox (the casting around the locating dowel) hitting the rear brake cross bar pivot mounting. This has meant having to fit a 1/2 chain link which is clearly less than desirable. Am I missing something here? Can anyone also advise how many links should the primary chain be.
On a Brum, a ½ link is also needed, you can be lucky to be able to have a new chain in the adjustable range, then, when it gets a litlle worn, you can remove a link
Sorry not much help.
I was about to ask the same question. I recently bought a kit of parts to build a late Shipley Scott, comprised of nearly all N.O.S. parts obtained from Holders at least 25 years ago.When I did a loose assembly I found the same thing ie. only 1/4 inch of movement on the gearbox, but all the Scott parts are so over engineered that I found that I could grind a lot of metal from the brake crossover lug and from the rear dowel boss on the gearbox to more than double the gearebox movement
A 1/4 inch is ample movement for the adjustment, if my memory is correct the chain is 69 links long including the spring link. there is nothing wrong having a Cranked link (or as you refer to a half link) in the chain so long as it is fitted correctly ie. no tightness on the plates. The weak point is the spring link,on some inferior ones the spring clip is a loose fit on the rivets and due to the movement will eventually fatigue. The use of cranked links is common practice in engineering, if you check a Renolds chain catalogue all manufacturers British and foreign have at least one or more models that use a cranked link.