The brakes on a standard 1VJ are adequate at best, diabolical if you ride a modern 1000cc sports bike.
So I'm on with improving them.
First thought was to buy a later XT600 twin piston caliper from a 3TB or similar. After a while a nice one came up on ebay and I've been looking at making a bespoke alloy mount. Unfortunately whilst this would be a solution, it's going to be a fair lump and for me would look a little cobbled together.
Then I went back a stage and purchased a pair of 3TB forks, which I knew were of the same diameter as the 1VJ. With the plan to utilise the original top and bottom yokes. What I didn't know was that they were around 30mm shorter. I don't really want to lower the bike by that much.
Then I thought I'd strip the fork down and see if the longer 1VJ tube could be used in the 3TB lowers. And that's where I'm up to!

Anyone got any thoughts or proven ways of getting a better two or four piston caliper onto an earlier Tenere?
I've already done the MX front end on the white 1VJ and I was hoping for a less involved conversion.
Are the 3TB yokes stepped to get the height back, or does that bike sit lower?

Why not use the later 4pt caliper, forks, disk and wheel hub? The forks are basically the same as a 3tb, just with the caliper mount further out to suit the larger diameter disk of the 4pt xt600. I believe the 4pt front end was also more or less the same as the 90s 660 tenere front end, except the 660 tenere had a disk guard, so theres that too.

From memory, my old 4pt xt600 had half decent brakes compared to my tenere. Its not a massive improvement, but would be easy to do.

Not sure on the length of the forks but the top fork clamps on the 4pt were stepped down a bit, but im not sure how much, it was a few years ago.

I've been looking on Fowlers and both the 3TB and 4PT appear to space the disc outwards from the hub with a spacer. Both with different part numbers.
Thankfully the twin pot caliper is the same number with the 3TB part number superseded by the 4PT, so at least my caliper will fit either.
I need to check the forks, it appears to have the long lower mount which would suggest it's a 4PT leg as opposed to the 3TB it was sold as.
Confusing.....

A quite common way would be to leve the caliper alone (aside from fitting better brake pads, the original ones seem to be better than the aftermarket stuff) and use a brake master cylinder with a smaller piston diameter. This makes the lever travel longer and the force of the wheel cylinder piston higher.
E.g. change a 1/2" for a 3/8" master cylinder. You can find smaller diameter stuff for scooters. Not sure which diameter the original 1VJ has, I assume it is 12 mm which would translate to 1/2".
The size usually is stamped on the underside of the master cylinder clamp.

Andy

I've sourced an adjustable ratio ISR master cylinder so that should allow me to get the brake force V feel equation right.

Would you be so kind to give me a link to that master cylinder, Dan?
I am very interested!
Thank you

Regards, Andy