This poor old bike has been extremely neglected by someone. Got my new tyres fitted and ready to install bearings/seals, and find my front wheel spacer between bearings was never there. Have tried the previously mentioned partzilla (couldn't access boats.net) for length of spacer but no joy. I know it's not possible to just measure up as its pressed between your wheel bearings but maybe somebody has info or a spare to measure?

The length of the spacer is not particularly critical, as long as it is a bit longer than the distance between the bearing seats, which you should be able to measure.

The thin disc near the middle is not important. It is there for when you are fitting bearings. You can hold a plain spacer in position with the axle while you fit the bearings.

Edited September 28, 20178 yr by feetupfun

So that thin disc you refer to is called "spacer flange" as per parts diagram? If so I'm glad its not essential because that's missing as well! What do people do that remove speedo drive, just replace with alloy spacer or am I having another dipole moment?

If you wait a day or so I'll see if I can find the original out of my bike, I made a aluminium version for my wheel when I increased the axle diameter

TY Trials has the spacer & flange for 6.24

https://www.tytrials.co.uk/trailandtrialsuk/prod_4340640-89-Front-Wheel-Bearing-Spacer-Flange-TY250-Twinshock.html

Speedo drive is in the brake plate, no spacers required to remove it or are you thinking of the wheel centralising spacer? Have a look at the wheel page on the site, they probably have all the parts that you possibly need

I'm very interested to learn more about increasing axle diameter. Presumably to run hollow alloy axle? 

Ah yes I was having a bit of a brain hiccup regarding the speedo drive!

I have an old myford lathe here so looking at turning all spacers/axles/steering shaft etc from alloy.

Well I machined a couple of aluminium spacers, saving 80g of weight in rear one alone but no comparison on front as I don't have original. One more question, how the heck does the speedo cable drive come out? Is it pressed in at factory never to come out or is there a way I'm missing? 

I changed the axle clamping system to what modern bikes run ie. no head sticking out on the clamp side fork & the solid fork threaded to hold the axle. From memory axle diameter became 17mm

My speedo drive has the remains of the cut off speedo cable, I assume the cables fuse to the drive fairly quickly when exposed to water. The drive gear on the brake plate was long gone when I got the bike

Biggest weight saving by ratio was making a aluminium steering stem to take tapered bearings, the stem weighs less than half the weight of the original steel 1 & uses a aluminium nut instead the special steel bolt