Couple questions about the dual caliper old style brakes

[sgallaty]

So the original brakes are a split unit, ambidextrous with a sealing surface between the two halves.

I've seen this caliper elsewhere, and the story goes that once you break the halves, you can never get them to stop leaking again.

Does anyone have any experience to the contrary? I was thinking maybe 3bond with the right torque etc. and I had some chance... ?

The reason why I'm interested in those calipers is that first, they are ambidextrous in that you can flip the stud over to the other half of the caliper and then mount it on the opposite fork leg for dual brake action (which I like), but also because I love the old style bar-over fender and only the older lowers have the bungs to attach them (and the bungs for the old style calipers)

so, anyone have war stories about rebuilding these calipers and them actually working?

 

[highspeedhamish]

The split design has been many times, FZ750 and RZ350 calipers could be split, replace the o-rings and things were fine. I think the problem could be is that old XS calipers are steel and not aluminum. Perhaps if the halves were lapped together after being split?

 

[XSLeo]

I think the leaky caliperscame from people that cheaped out and reused the old o-rings. Put in the new o-rings and they should be fine. I have read some where the bolts that hold the halves together should be replaced as well.
Leo

 

[5twins]

I think many people just do shit work. They don't clean the parts properly or enough and they don't torque things evenly. This isn't rocket science but it might as well be for some, lol.

 

[sgallaty]

I know there are people who don't try to do good work, but there are also plenty of people who just don't know any better.

I have plenty of donor engines from those people.

 

[CDNTX650]

i split mine and rebuilt it with a mikes kit. works effin great with no leaks. with a new m/c and lines. and pads. ha.

 

[5twins]

Yes, these were a nice brake in their day and still aren't bad today if working properly and set up with stainless lines, good pads, etc. Go to SpecII, an RD350/400 specialist, for stainless lines for the old style caliper. I think they carry the Speigler brand which is very nice. $45 for a single one piece front line.

 

[TeeCat]

i split mine and rebuilt it with a mikes kit. works effin great with no leaks. with a new m/c and lines.

Me too. If it's the early-type caliper you're speaking of, I can't imagine why someone would re-use old seals when a kit is $22.00. I just split and rebuilt mine with a lot of help from folks here, and we'll see about leaks. Where I did have a leak during bleeding was the upper-to-lower hose junction, not the caliper. The little O-ring between the halves is actually a pretty stout little piece. I did not replace the bridge bolts.

TC

 

[sgallaty]

i split mine and rebuilt it with a mikes kit. works effin great with no leaks. with a new m/c and lines. and pads. ha.

were the pistons rusted in yours? I've got two of them, and in one the pistons are pretty rusted.

 

[TeeCat]

I know you're asking CD, but in mine, the pistons themselves cleaned up nicely. The outer sealing surfaces came clean with a rag, and the rest with wire brushes on a dremel.

The bulk of the cleaning for me was of the seal grooves and pots themselves, but the dremel brushes and dental picks worked nicely. Mike's and HVC Cycle have pistons if you need them. In a worst case, HVC sells new complete calipers, ready to install and bleed, though they're a little pricey.

Thought that might help.

TC

 

[CDNTX650]

were the pistons rusted in yours? I've got two of them, and in one the pistons are pretty rusted.

yes, i replaced them with the new ones from mikes along with new seals. used scotch brite to clean the rust inside the calipers and really smooth them out, then 2000 wet. no leaks after 1000kms yet.