Hi Guys,

Don't seen to be able to find the answer to this.......

Can anyone put any light on as to the year when Vokes Filters were first fitted to m20's
They had to have a different tank fitted to tank the route of the hose past it at the seat I believe in the righthand corner?

Many thanks.
Regards,
Paul

email (option): eastwood007@ntlworld.com

Hi Paul,

The notched tank to allow the induction from the tank mounted vokes filter was introduced in 1943. However not every machine was fitted with the filter, even thought they had the notched tank.

Regards

Rosco

Thank you Rosco,

The date was important to me.

Thank you again and for your time to reply.

Regards,
Paul

email (option): eastwood007@ntlworld.com

For most of the war, the tank top filter was a 'fitted as necessary' accessory for some theatres. Oddly, even in the desert, use doesn't seem to have been universal.

I can't, offhand, think of any photographs showing the Vokes in use in NW Europe. There is photographic evidence of them being fitted on the production line from contract S5209 onwards. This was scheduled for delivery from July 1944 but it may well have commenced later.

As a standard fitment rather than an in-theatre modification, it would seem that you'd need to be looking at frame numbers higher than WM20 104818 at the very least...but even then it may only have been those machines intended for the Far East which were so equipped.

As was implied in an earlier thread the tank-top Vokes ticks all the boxes as a must-have, essential fitment on a WW2 WD motorcycle - until you start looking for period parts lists and photographs of particular units in given theatres.

I don't think it's any co-incidence so many NOS or as new Vokes boxes have turned up in Australia as they seem to have been widely used there...but that seems to have been about it.

There were extensive air filter experiments before the war and several 1930s Norton contracts had the rear type fitted but they were rapidly dropped..I can't think why unless there was a substantial performance disadvantage or perhaps detrimental effect on fuel economy.

The 'cut off tank' was fitted for the last three wartime contracts according to the parts lists...The filter itself was only fitted to the last two contracts according to the lists...Ian

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

Hi Guys,

Thank you all for reply.
Very helpful and much appreciated.

Regards,
Paul

email (option): eastwood007@ntlworld.com

And they turn up down here because we used them in the Pacific and then in Korea.
The northern forces used them till the 70's when the last of the M20's was decomissioned.

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

Early wartime Nortons in Australia with tank top air filters.