This is what I first thought Ian, but all the information I can find points to it being the other way.
There would be more offset on the left hand side due to the hub.

I await to be prove wrong.

I've just fitted my rear chain and the sprockets looked at each other close enough?

Mark

email (option): pes.sales@btconnect.com

Another forum member has helped with the information I needed,
Thanks

email (option): Alwyndart@gmail.com

Here are some details for the rear gearbox plate spacers.

No8 left side spacer #66-4602 = 1.6" long.
No9 middle spacer # 15-6240 = 2.5" long.
No10 Right side spacer # 66-4601 = 1.75" long.

Ron

email (option): ronpier@talk21.com

I think Mark is correct - here is a pic of a set I made for someone a while back. There is quite a kink where the brake stay is fitted and that is where I have the 1 3/4" one fitted in this photo.
The shorter one is 1 9/16".

I stand corrected if that is the case! In which case I think Drags have them listed wrong too.

I've asked Bastiaan if he wants to include it in "technical"? If so it will need to be amended. Ron

email (option): ronpier@talk21.com

Ron, I will have a closer look tomorrow as I'm only going by this picture I took at the time.

Ray

['I stand corrected if that is the case!...']

Likewise...I've never fitted them that way over many M20, M21,M33 and B Series rebuilds without any apparent issues, in fact I recently fitted them to mine...Taking into account the 'flexibility' of the M20 rear frame I guess I may just have been lucky!...
Forunately it's not too late to reverse the order of assembly if it turns out to be incorrect...Ian

email (option): ian@wright52.plus.com

From a previous post on the subject...Info. from Neale Gentner....It's beginning to look like I've been wrong most of my life...:laughing: ...Ian


[ '66-4601 Chainstay bridge distance collar, 3/8” clearance bore x 1.595” o'all, waisted, right side, (shortest of the 3 x 3/8” bore frame spacers) common to all 1937-1960 500cc & 600cc rigid frame singles 1 per machine.

66-4602 Chainstay bridge distance collar, 3/8” clearance bore x 1.763” o'all, waisted, left side, brake stay is fitted between this spacer and left side frame lug, combined extra length of both makes up for offset of rear frame which accommodates chain & brake etc, common to all 1937-1960 500cc & 600cc rigid frame singles. 1 per machine.

15-6240 Chainstay bridge distance collar, 3/8” clearance bore x 2.500” o'all, waisted, fits between rear engine/gearbox plates, common to all 1937-1960 500cc & 600cc rigid frame singles. 1 per machine' ]

email (option): ian@wright52.plus.com

The easy reminder is that the RHS spacer has the same length as the thick one in front of it as the gearboxplates should run parallel with the RHS bottom frame tube.

BR, Michiel