Fork legs

[Lonerider]

HI Guys new on this site started a hard tail build that I've got my hands on so have little info on what parts are already there !
Basically Its a 1979 XS650 which came without front brake caliper ,the mounting is on the right fork leg,so I got my hands on a front caliper for a 79 bike great !! whoops it don't fit
Ok help now Please the forge legs have the following markings in the castings
6JB-R Y1 on the right leg
20Y-L Y2 on the left
can any body identify which bike these came from to enable me to get my hands on correct brake caliper

 

[gggGary]

toss us a pic of the leg AND that caliper. We'll be able to ID pics quicker than some casting numbers.

 

[Lonerider]

How do I get pics on ???????

 

[Lonerider]

Whoops done it lol
Hope these help

 

[DogBunny]

The caliper is correct, and the fork at least looks correct. Are you saying the distance between the bolt holes is different? Why doesn't it fit?

 

[Lonerider]

[Hi ya ,the caliper has hole centres of 112mm ,were as the fork legs are 100mm/I] ????

 

[DogBunny]

Your fork legs are not from an XS650.
The easiest solution would be to get a pair of 35mm XS650 legs.
A picture of your triple trees would help so we can tell if they are off of an XS650 and are for 35mm tubes.

On second look, your fork legs don't look correct at all.

 

[gggGary]

Looks like the wheel has the smaller euro front rotor? Usually those were used in dual disk set ups. I think that fork leg has the holes set high for a larger diameter rotor than you have there.

 

[XSLeo]

XS650's from 74 up had caliper mounts on both lowers. This lets you use either a single or dual set up.
The 74 up to 76 were 34 mm tubes, in 76 they moved the caliper from the front of the leg to the rear. these all used a dual piston caliper and about 82 mm bolt spacing. In 77 they started the 35 mm tubes and used the caliper you have, it has about 112 mm spacing.
Leo

 

[Lonerider]

mmm getting confused now
Not sure at all what the forks are off

 

[gggGary]

OK I was kinda sure I knew and went out and checked in gggGary's shed of ill repute. They appear to be early FZR600 forks. Which is a good thing the FZR rotors will bolt (with spacers) to an XSwheel. Calipers are about a dime a dozen.



stock photo of a 93 FZR600

Well yours are sllightly different there is a bit of a bevel above the axle flat but I think we are in that genre' the rotors are 298mm just like the US spec XS650 rotors but are designed for the multi piston calipers and have less offset.

 

[racerdave]

Gary, the poster fork doesn't have a drain screw? Does that change your FZR thoughts?

 

[gggGary]

Yeah there are several detail differences. But there's gotta be a drain screw somewhere?
In Europe, an FZR750?

 

[Lonerider]

Cheers guys I'm now looking at FZR route
This is the probs one gets having bought a project bike that needs completing with unknown parts origin lol