Having a bit of 50 mph fun in Belgium last year, photo taken from the pillion seat of a girder rigid Norton ES2

That must be one of those rare experimental WB33's Ron

email (option): ronpier@talk21.com

As rare as hens teeth.
I think its the bike the ministry should have chosen.
Im currently slowly rebuilding the sidevalve engine? But not in to much of a rush as the OHV is nicer and gives a better tank range. With the SV I had to refill it every 90 miles, now I can get near 200 on a tank full.

Hi Peter...I've often been tempted myself...10 more bhp even with a standard B33 lump, an 80-85mph top wack with a fuel consumption always in the mid 70s and a higher cruising speed...it's a no brainer...

I try to console myself with the 720 engine in my M20 which goes better and uses less fuel than the standard engine (and the fact it still looks standard)..but even that isn't as good as a B33 ...Ian

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

I know what it is like, my Ducati Monster 900 used to do around 90 miles to the tankfull.....

Hi Peter..That seems a rather high fuel consumption even for an M20...The tank is 3 1/4 gallons...Assumming it was full when you stated out and you had, say, 1/2 a gallon left when you filled up that leves 2 3/4 gallons.

That only works out at 32 MPG..and even if you were 1/4 gallon 'shy' of full that's only 36MPG....Ian

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

Ian
When there was a thread going a couple of years ago about fuel consumption I measered mine between top ups and found it to do about 35mpg, 40 at best with the sidevalve engine in.
When I was asking advice here about fitting the OHV engine I was told that I would have to alter the petrol tank to clear the taller OHVs. But the tank that is on my bike is a bit of a mystery, as it has the right hand side cutaway for a Vokes air filter, but also the cutaway to clear an OHV engine.
Now I know how to post photos here I will get a few photos of it up to see if anyone can ahead any light on it.

I know that engine will offend the purists but I like it, and the bike makes plenty of miles. The sidevalver and all the bits to refit in a couple of hours are here, so when my kids sell it after I am dead the next owner can put it back to standard if he wants to.

Peter, I think the more a bike is used..and particularly the more miles it does, the less concerned people tend to be about originality and the more likely they are to change things.....

It's certainly the case that I generally 'improve' things, as I see it, where the opportunity arises..Both my B33 and my M20 are fitted with oversize engines, stainless for durability and a modern electronic replacement regulator for example...That's nothing new, people have been modifying their bikes from the very earliest days of motorcycling.

In fact, the idea of NOT altering them is the more modern phenomenon, being a view that has only been expressed in the last 35 years or so....

Of course changes such as this and your modification, can justifiably be regarded as altering, to a degree, the essential experience of owning/riding the original bike...Plainly, no one is going to find out what riding an M20 was like by riding mine, though they will get a 'flavour' of it....

Personally I've done enough miles on standard BSA heavyweight singles to have a very full appreciation of that experience, so I don't worry too much about the views of the purists...

These days I like to exercise my imagination a little more and perhaps explore the limits of what can be done around the original idea to improve various aspects of it...That shouldn't really offend anyone, should it?....Ian

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