Buckminster
XS650 Member
I am trying to get a XS650B with 16,000mi up and running that has not been driven (regularly) for about 20 years. I finally got the thing tuned enough to start driving it around the neighborhood and noticed that the front brake was binding. Upon closer inspection, there was some sludge build-up behind the caliper pistons. Once cleaned, I am still having a hard time telling what needs rebuilding vs. replacing. I vaguely remember putting in new caliper seals about 10 years ago. Other than that, I believe everything is original OEM parts. I’m using a Clymer manual and will reference some of the specs below. I have several questions for anyone with some front brake experience under their belt. I’ll try to keep it simple:
1. My rotor thickness in shy just of 0.25” but visually looks ok. My manual says replace if less than 0.26”. Can anyone confirm the minimum depth until replacement?
2. My caliper pistons have some pitting. See photo. As far as how they were wearing on the seals, the 10 year old caliper main seals looked ok but the dust seals looked worn (they may have been older.) My first choice to reuse if possible, my second choice is the stainless set on ebay.
3. I was going to order the caliper seal kit from Mikes unless anyone got a good reason not to.
4. My master cylinder body at the handlebars has stripped mounting threads at one bolt and the overall condition is questionable. See photo. Has anyone had any luck tapping the aluminum for the next bolt size bigger? If I were to replace it, am I better off getting a new cylinder body from Mike’s or finding a used original? There is some minor tarnish on the piston bore wall.
5. I have no idea how to gauge the condition of the piston assembly. See photo. My manual basically says replace anything that looks worn. The rubber cups looks good to me but there is minor surface rusting on the shaft. If it can/should be rebuilt, are there any really good kits out there?
6. My manual also says replace brake lines every four years. They look good and I do not see any checking. Is there a more a cost effective rule of thumb on when to replace?
Any help would be greatly appreciated. Watching this thing sit while everyone else is summer cruisin' is driving me crazy!
1. My rotor thickness in shy just of 0.25” but visually looks ok. My manual says replace if less than 0.26”. Can anyone confirm the minimum depth until replacement?
2. My caliper pistons have some pitting. See photo. As far as how they were wearing on the seals, the 10 year old caliper main seals looked ok but the dust seals looked worn (they may have been older.) My first choice to reuse if possible, my second choice is the stainless set on ebay.
3. I was going to order the caliper seal kit from Mikes unless anyone got a good reason not to.
4. My master cylinder body at the handlebars has stripped mounting threads at one bolt and the overall condition is questionable. See photo. Has anyone had any luck tapping the aluminum for the next bolt size bigger? If I were to replace it, am I better off getting a new cylinder body from Mike’s or finding a used original? There is some minor tarnish on the piston bore wall.
5. I have no idea how to gauge the condition of the piston assembly. See photo. My manual basically says replace anything that looks worn. The rubber cups looks good to me but there is minor surface rusting on the shaft. If it can/should be rebuilt, are there any really good kits out there?
6. My manual also says replace brake lines every four years. They look good and I do not see any checking. Is there a more a cost effective rule of thumb on when to replace?
Any help would be greatly appreciated. Watching this thing sit while everyone else is summer cruisin' is driving me crazy!
