Starting rebuilding. First, brakes.

[ram_may]

Hello everyone.

I’m new posting here. Some years as member, But I hadn`t time to start my rebuilding nor knowledge to participate.

I bought some years ago one beautiful, rusted, dirt and long years asleep XS-650B (born in 74-75).Since I´m living in Spain, and the bike never was sold in Continental Spain, there aren´t old donnors. Only was little dold at my home (Canary Islands, free from Franco´s protectionism).

I am starting my task now. I don´t want do big aesthetic changes respect the original. Only:

• An RZ-350 PMA
• Steering Bearings
• Bronze Swingarm Bushings (or AllBalls Bearings????).
• Frontal oil radiator (like XJR-1300, example)

As slow I go, the difficulties arose. Now, I´m circling around the front end.

I bought the round Master Cylinder (identical to the original). Now, the old caliper is death (Impossible to extract pistons. And even if I could, I wouldn't trust the rebuilding). So I´m thinking in two options:

1): Buying a new copy (Heiden) of the caliper (04 '74-'76)
2): Buying a dual piston caliper and adapt. Maybe from a XJ-600 (1984) or a XV-1100 (circa 1989).

Have someone put the XJ-600 caliper into the steel XS disc?
Could it be good combination?

I have many many doubts. Hope to resolve all, and someday bring my dear to live again.
Wait for your advice. Thank you much in advance.

 

[fredintoon]

Hello everyone.

I’m new posting here. Some years as member, But I hadn`t time to start my rebuilding nor knowledge to participate.

I bought some years ago one beautiful, rusted, dirt and long years asleep XS-650B (born in 74-75).Since I´m living in Spain, and the bike never was sold in Continental Spain, there aren´t old donnors. Only was little dold at my home (Canary Islands, free from Franco´s protectionism).
View attachment 194368
I am starting my task now. I don´t want do big aesthetic changes respect the original. Only:

• An RZ-350 PMA
• Steering Bearings
• Bronze Swingarm Bushings (or AllBalls Bearings????).
• Frontal oil radiator (like XJR-1300, example)

As slow I go, the difficulties arose. Now, I´m circling around the front end.

I bought the round Master Cylinder (identical to the original). Now, the old caliper is death (Impossible to extract pistons. And even if I could, I wouldn't trust the rebuilding). So I´m thinking in two options:

1): Buying a new copy (Heiden) of the caliper (04 '74-'76)
2): Buying a dual piston caliper and adapt. Maybe from a XJ-600 (1984) or a XV-1100 (circa 1989).

Have someone put the XJ-600 caliper into the steel XS disc?
Could it be good combination?

I have many many doubts. Hope to resolve all, and someday bring my dear to live again.
Wait for your advice. Thank you much in advance.

Hi Ram,
yes! First, make sure it'll stop.
Try removing the front brake caliper pistons by removing the caliper's bleed nipple replacing it with a grease nipple and pumping the caliper
full of grease with a side-lever grease gun, A good quality side-lever grease gun will give several 1,000s of psi.

 

[Signal]

Another way is to use the brake master cylinder to pump the pistons out, just top up the fluid. A messy but effective way if you dont have a grease gun. Compressed air is dangerous as the pistons fly out at great speed.
There are lots of brake conversions do a search the most popular are Brembo and Yamaha blue spots off an R1 or R6. If you go down that path you will need a smaller master cylinder around 10mm piston. I have a 10mm master cylinder on a R1 caliper and the feel suits me.
You will need to cost it out but in you situation a reproduction may be the best solution.
Unless your rotor is shot in the altenator fixing the existing system may also be a better alternative to a PMA.
I would go for the bushes in the swing arm over the needle bearings.

 

[gggGary]

Hi Ram. Some ideas.
The Brembo (or knock off) caliper is popular, a Blue spot cailper from the later Yamahas are also used, they may require a bit of filing to clear the spokes.
Calipers designed for bikes with narrow mags are often too deep and interfere with spoke wheels.
Some links to guys doing it here. https://www.xs650.com/threads/brembo-brakes-what-bikes.35608/#post-360478
Swing arm; stick with the bronze bushings, needle bearings with limited range of motion seldom last/work well.

 

[ram_may]

Hi again, friends.

Finally, I have brake caliper ready to restore.

Thanks to fredintoon advice, I took out the pistons with a gungrease. I didn’t wanted to use my new master cylinder to do it (Thanks, Signal ), because wanted to preserve it clean to the day of assemble it all.

Surprisingly, pistons were in pretty form. No rust, brilliant like new. This gave me confidence to use them again, so by the moment, no R6 caliper (Thanks very much, gggGary ). I will buy a rebuild kit at Yambits (The only by now in Europe).

I have a new harness, new petcocks, and wheel bearings. Just today I received the bronze bushings. One more little step in the long way…. Carb rebuild kit, Oil filters, carb holders coming. Soon, I’ll buy somewhere Steering Bearing Kit, brake pads, cables…. (a looooong way).

Thanks all. Soon more

Postscript:
I found a locksmith in my town. He disclosed the code key from my gas cap. Same as the ignition key.
Friends, I advise you to look for a competent locksmith. 3 Euro each key copy at no additional charge to find out the code.

 

[xjwmx]

Only thing on your bullet list that is probably necessary is the swingarm bushing. Bushings better than bearings since limited rotation + weight. For steering I still have ball bearings. Overtightening will ruin them, and if that's happened, might as well replace with modern. Nothing gained replacing charging, if original can be got working. Radiator totally uncalled for