Fork leg lower swap compatibility

Hey guys does anyone know if I could swap a 550 left fork leg lower onto my 650 maxim left leg?

Wanting to run a radial brake caliper instead of the pivoting maxim one.

Thanks

 

Diameters are different, as are the fork tube bushing arrangements, and several other things.

None of the XJ series mounts their brakes radially. For that you'll need to do a front end swap from a much newer motorcycle.

 

Thanks for clearing that up
They both have 35mm tubes though ?
So will just need to find a pair of complete 550 forks

 

650=36mm tubes 550=35mm tubes. I am fairly positive on the 650, not 100% on the 550 but they are definitely different diameters

 

Yes sorry 650 is definitely 36

This list states the 550 maxim is also 36

https://www.kiwavmotors.com/en/faq/about-fitment/23-motorcycle-fork-tube-size-chart

 

The 550 Maxim does have 36mm tubes, but there are internal differences that make swapping the lower over unwise.

It's the 550 Seca that has 35mm tubes.

I think we need to know what your goal is aside of having different brakes.
If you are looking it improve the braking performance just swapping to another type of single piston/ single caliper system won't gain you anything.
Have you rebuilt the brake system?

If you want improved braking performance over stock, then you'd be much better off by swapping in a Seca 650 fork, either of the XJ750 forks, or something from a newer machine (like an R6).

 

Thanks for the reply

I have a set of early Yamaha R1 callipers that I wanted to fit to my custom build on my xj.
Already running the master cylinder and new braided line as well as a new seal kit in the stock xj calliper.

Unlike the 650 maxim you can make adaptor plates to fit the R1 calliper on the other style of fork legs.like the photo I have shown.
Ideally a whole front end swap would make more sense. I just already had the R1 brakes and just needed to find different fork legs to suit the modification.

Thanks

 

You could have a talented welder fabricate new mounting lugs for your existing fork lowers. Might cost you more than a few beers though.

 

I did think of this thanks moe
The brits used to do this quite a lot.
Might be the way forward.
Thanks mate Always great at replying!
My new jets are on their way & same with a colour tune. Will post outcome on my other thread.

 

Ooo, really - welding lugs on the outside of the tubes? I don't think I'd want to bother, any distortion and the machined internal bore is toast - isn't it?
The 36mm os dia is quite common, although only on early bikes, my Kawasaki 750 uses 36mm xt550 rods (stanchions in the uk), selected for their extra length over stock.
All in all though, the front end swapping is a total minefield thats difficult to cross without prior knowledge or a breaker willing to take returns.

 

The heat control you get from a TIG will allow that sort of welding with out distorting the bores.
Like I said; a talented welder.

 

Im

I’m a light fab Enginer as a trade so tig is second nature. Tig’d the whole back end of my xj.
But we have a very talented custom bike shop in town so will run it past them.
http://thebikeshed.cc/bike-builder/pacific-mc-co/

A fork swap would also benefit with a upgrade in suspension performance too.