I've just bought a WM20 in bits in boxes.
I need help with all the spacers that go around the engine and gearbox plates. I do have some obviously correct ones.
Does anyone know of a drawing that gives the dimensions of the spacers. There is one set of spacers to go below the gearbox rear. Another set to go at the front of the gearbox. Any spacers at the very front at the bottom of the downtube?
I'm in the UK in a place called Potters Bar.
Any help very much appreciated... Jon

email (option): jonsewell8@hotmail.com

I'll send you a drawing by email.

Henk.

email (option): ahum@quicknet.nl

Henk, that must have been a world record for speed of reply..thanks.
So there are no spacers at the front of the frame.
You have supplied the dimensions at the back.
Do you have the size of spacer in the middle on the right hand side?
I need to get these right as there is a small repair required to the rear part of the frame.
Thanks again Jon

email (option): jonsewell8@hotmail.com

Hi Jon,

I don't have these here right now. I'll see what I can find.

Henk.

email (option): ahum@quicknet.nl

The gearbox plates run parallel with the righthandside lower rearframetube, so the length of the spacer just behind the engine has the same length of the spacer behind the gearbox on the righthandside. Which is 40 mm.

Also the top RHS frame tube which goes to the saddle is in the same plane as the lower.

Hope this helps, Michiel / NL

email (option): m.wijbenga@hotmail.com

Jon, I've sent you some pictures of all four spacers in place - I just made some for a bike here. Ray

Thanks to all of you for your help. I can now repair the frame. Best wishes, Jon

email (option): jonsewell8@hotmail.com

Hi Henk, Ray and Jon

Could I also have the details and photos you mention.

Many thanks.

Martyn

email (option): Gwyndwr@icloud.com

Hi Jon
if u miss any parts i will try help you also
cheers
Hussein

email (option): sl_hussein@yahoo.com

Martyn, you should have them now.

Old thread, but it's what I'm fishing for too. Specifically, dimensions on the rear outside frame-to-gearbox bracket spacers.

email (option): bob@combshouse.com

email (option): bsansw1@tpg.com.au

Definitely yes, it's best to put any useful information there unless we want to cover the same topics ad infinitum...Ian...

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

I looked for a drawing there, but didn't find one.

email (option): bob@combshouse.com

If possible i would also like a copy of this information as i am at this stage of the restoration.

Cheers,
Mark

email (option): skid1@live.com.au

me as well pretty please

email (option): chris.astinbarker@btinternet.com

Morning all,
I would be most grateful if anyone who has the above information could please forward it on to me. I've looked in the technical section and can't find it.
Thanks
Alwyn

email (option): Alwyndart@gmail.com

Anyone can submit information for inclusion on the 'Technical Section' but sadly it is an underused and under supported resource....It a shame more people don't contribute to, as well as take from, the website generally as it would further improve the experience...Ian

email (option): ian@wright52.plus.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

Did the possibility of acceptance to to the illuminati not cease with Henk's sad departure ?

How can one be considered an expert, zonder Henk zijn goedkeuring ?

Ron, I think you have the lengths of #8 #10 the wrong way around.

I've questioned this in the past, but as usual no responses.

Mark

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

The shorter spacer (8) allows for the width of the brake torque arm....Ian

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

As Ian said. I'm fairly sure I have it the right way round.

Ron

email (option): ronpier@talk21.com

The difference between the spacers is .150" which would make the rear brake torque arm 8 SWG (.144")...Ian

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

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

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