Firstly I'm gat crashing not an owner but I had an M20 on loan from HM Queen from 159 till near on 1970. I have writeen articles for the MVT & sent all my paper work to their Libarian.
Listening in to a conversation between 2 M20 riders at the weekend i nearly fell over in awe at the speeds they were stating they get from their machines. On Convoy duty in BAOR as Distance control Motorcyclist ( RASC) and more to the point Convoy floater Ie, on point duty till the last truck REME had past get over to ones machine & hope to hell she would start cos although leaving her running ( Chargeable Offence) bet yer bottom dollar she'd stalled. Mount ones bike & chase after the so called 30 miles i the hour convoy. Many time I must have looked like George Formby in No Limit flat over the tank trying to catch em not only catch but to pass them for the next intersection. Many a tome Green Uniformed German copper on his BM would pass giving acheery wave or was it hurry up. Speed following wind down hill 58mph normal juston 55 with every not & bolt shaking as well as the steering which one holding on for dear life praying that nobody stops suddenly. Some riders of today put us to shame then.

email (option): pa.mfwood@virginmedia.com

Hi Paul

Welcome to the forum, I'm intrigued as to the paperwork you sent to Mrs Anstee.

But to return to your question about speed, I've heard some pretty elaborate claims myself, I did manage to push an oversized M20 up to an indicated 65 once, but the speedos from that period may not be that accurate so who really knows.

But apparently if you park an M20 in the garage pointing West because of the earths spin it is travelling backwards at nearly a thousand miles per hour without even starting it.

Rob

email (option): robmiller11@yahoo.co.uk

And of course the earth is travelling through space at approx. 65,000 mph...Ian

Hi Woodie. Military Ron here. If any of your recollections refer to my own speed comments on the other forum? Perhaps you are not aware, my engine is to M21 spec (600cc) and is easily capable in excess of 60mph. Some of the other forum members here are running M20's that are 720cc. Ron

email (option): ronpier@talk21.com

I have one WM20 which I built
And with 19T in motor to gear and 18T final drive, and can do about 56Mp/H on very high revs.
Could do more, I guess, with higher ratio.

The other WM20, I bought after it was standing for 10 years in a back yard covered with canvas and I did not repair or touched anything at all on it,
It, has a thick gasket under the barrel so low comp –ratio, and when I took the barrel head off,I saw chips all around top of sleeve, (guess that’s why they put the thick gasket under barrel)
it seized on me on a 150Mile drive and freed right away,
And still, somehow drive very strong and doing 65Mph measured on car, a Harley and Suzuki, so must be correct..
All with standard 500cc and 276C/1B carb. How? I don’t know…

(Did not check the ratios on this one)

email (option): noam10@gmail.com

Earth speed of rotation in a garage that sits at the equator would be just over 1000mph but if the garage was in the UK for eg. It is closer to 400mph.

I was out for a lane thrash earlier & reminded yet again that for stress free riding, sticking below 55mph is best policy with the limitations of those girders & the authentic 40's bomb craters/potholes my local council "painted circles around" about 6 months ago.

I agree Fred. Up to 55mph is as fast as I normally want to ride my M20. But on this rare occasion, I just didn't want this cheeky whipper-snapper on an old Velo MAC to get the better of me. My bike was pulling like a train but I had to back off at wobble factor 58.

I have noticed that my front wheel is not central in the forks and that my tyre is wearing more on one side. So I'll be getting my wheel re-built and a new K70 and also check my forks out.....although I'm quite sure they're not bent. Just need to decipher those bottom measurement? Ron

email (option): ronpier@talk21.com

When I first met my girlfriend, she lived quite a way away from me and the quickest way was to get there was down the motorway, I noticed that if I was in an empty lane my bike was handling well up to the 65MPH mark, but if I was behind any traffic such as a truck, it used to wobble, it was always the same predictable wobble that never got any worse, I tried messing around with the dampers as I was behind the truck but nothing seemed to cure it, maybe it is the prescision streamlining of the M20 that caused it!
Maybe it was the slipstream of some slightly distant lorry that caused it, mine never did it if it was an open road only behind something large(ish). I never found it disconcerting, I just accepted it as a foible of the M20

email (option): davmax@ntlworld.com

I've had my M20 into the mid 70s fully loaded with camping gear on the Omaha beach road...(clocked by Ron himself, following in his BMW car.) and have gone over 60 on the beach near Cherbourg..I think it's fair to say the steering felt light and a little vague on both occassions but it couldn't be described as a 'wobble'. I go 60 plus on the road regularly wth no ill effects...though I have noticed the effects of 'turbulence' mentioned by Dave.
I think if there is an actual wobble it should be investigated and not regarded as a feature of the bike..It may well be an indicator of the presence of a more serious problem...Ian

That's right Ian. I'll be pulling my forks apart soon looking for something wrong, apart from the obvious wheel and tyre. Ron

email (option): ronpier@talk21.com

Ron I like a challenge but I can't work those bottom measurements out on that diagram at all.
Ive not had a wobble at speed with girders either (had one shake over 50mph from being seriously out of ballance once) but I think If I were you I would check a few things with plumb line & spirit levels, I like to get the headstock, engine plates & back wheel vertical. Ive seen bikes with perfectly good wheel alignment when measured using a plank along the bottom but a rear wheel not vertical with the headstock or front wheel.

May be he can help?

Hastings, East Sussex,

http://www.sumpmagazine.com/classicbikespecialists/

Hastings, East Sussex,

Or as no one of the British mentioned him,
I am missing something?..

email (option): noam10@gmail.com

on a standard machine, i travel on major roads usually around 50-55mph at half throttle, once when going down a long downhill gradient it crept upto 68mph before i noticed it, the dilithium crystals were a little drained but all seemed ok after this short warp speed trip.

Just read my post.. I meant front wheel was out of balance, that can cause noticeable shake at over 50 & forks that losevtheir responsiveness.

Noam, yes Jake Robbins has alot of respect as a girder refurbisher.

I would take a pair of curved calipers to an event & take axle width measurements from lots of m20's also other things like wheelbase & link length etc ...

I am surprised that the forks are not symmetrical!,

Is it because when BSA added the speedogearbox to the leftside that they not only shortened the width of the fronthub but also had to pull out the fork out of symmetry to make room ?? I can't imagine it was designed this way in the first place.

Anyone ideas ?? Michiel

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

Yes I like young Jake a lot and have used him on a few occasions. But what can I say! Jake re bushed these forks for me 4-5 years ago and after only about 2000 miles the bushes were worn away to tissue paper. When I removed them I found he had used the wrong bronze (sintered bronze). I have replaced the bushes with the aid of an engineer friend. But I feel I should have spoken to Jake about it. When I remove my forks in a few weeks, I might just make a trip to Hastings for his appraisal and comments. Ron

email (option): ronpier@talk21.com

PS. I think those measurements are 2 19/32" and 3 3/32".
But I'll be checking some M20 forks tomorrow. Ron

email (option): ronpier@talk21.com

a couple of years ago my B31 assertained a speed of over 100mph wow!! but it still was doing 100mph+ in the shed one speedo off for repair

email (option): roger.beck@node6.com

Fitted new correct carb yesterday. Virtually all new engine now but when testing top speed today - no more than 84km/h (52mph) Any tips for fine tuning?

I don't know how many miles your rebuild has done, but after running in it took 3000 to 4000 miles for my M21 to loosen up and its still getting better at 8000 miles

Cheers Pat

What sprocket have you got on the motor Kalle

Job

email (option): Jonnyob1@googlemail.com

What sprocket have you got on the motor Kalle

I changed mine to a 20t and experience a much smoother motor

Job

email (option): Jonnyob1@googlemail.com

Hello, I have done about 1000km (621 miles) after rebuild. I have both engine and gearbox sprockets 19 teeth.

Kalle if you ride a standard M20 in mostly flat areas, you could increase the engine sprocket size by one or two teeth. But this will have an adverse affect on hills. Ron

email (option): ronpier@talk21.com