Paul Klmapers vs chainstay internal routing

[rmhurley]

Has anyone successfully used Paul Klampers as their rear brake on a bike with internal routing through the chainstay? Im considering a new frame and most of what I’m looking at have internal cable routing. On my current steel bike the routing is all external. It came with a tekro cable disc caliper which has a much narrower profile. When I put the Paul on there, I had to bring the cable around on the outside of the chainstay. I have heard of people testing this with internal routing and needing to bypass the internal routing completely to make those brakes work. Just wondering if anyone has set up say a Giant Revolt, Santa Cruz Stigmata or Niner RLT type of carbon frame with Paul Klampers and how it worked out.

I suppose I am just trying to determine whether or not the Paul’s are inevitably incompatible with the majority of internal routing where the cable pops out in the inside of the chainstay. Id like to be able to use them on a new build should I get a new Frameset.

It seems like there are quite a few sale frames around right now but if in the end I’m having to buy almost all the components over again I might opt to use the steel frame I have and maybe just replace the fork and wheelset for something lighter.. I could use the money for a much higher end set of rims if I’m not buying a new frame. An input is appreciated. Thanks

[.RJ]

I have this setup - its not ideal for sure, but, in practice its working just fine with compressionless housing.

When I had the bike built I had planned on using hydro brakes, but with covid and parts availability and then with issues getting Hope calipers to work, I went mechanical. In retrospect I wish I'd run an external hose and BSA BB.

[Mark McM]

The S-bend stays don't help with RJ's bike. With more traditional straight stays, the cable/housing run would not have been as curvaceous. How well the cable/housing routing works with Klampers is going to vary from one bike to the next, depending on the location/orientation of the cable/housing exit hole on the stays.

[rmhurley]

Thanks for this. Looks just as I imagine most internal routing would end up bending after the cable exits the chainstay. Makes me wonder if a straight rather than s bend stay would change decrease the angle of the curve enough to make any noticeable difference.. I realize that would change the look and maybe even ride of the rear end and I know that's usually a key design choice in a custom build--one I also opted for on my custom Fitz rando bike (that bike has rim brakes.)

I can see why generally defaulting the housing exit point there is the obvious choice as it leads the cable out to the inside of the bike making it less likely that it would be impacted in a crash, but i do wonder, if, on a custom frame, a builder might route it to the outside or even just on top of the chainstay with the knowledge that bike would be fitted with these brakes. it seems that it would also work in the future should the bike need to be set up with hydros or some other cable caliper that had a more inline design.

Do you think that the bend in the last few cm of the cable makes any difference to the quality? From my experience, the Klampers could lose a little bit of power and still have plenty to spare so i wouldnt worry so much about that aspect, but I do tend to get my bikes dirty and after a little while i wonder if the bend in the cable might get a bit sticky.

As to the bsa bb, I can see plenty of reasons to have a custom designed for this standard but I can't see how it pertains to this exactly? Do you mean that you had your custom built with a larger bb area so that the housing fit through the cluster? thanks again for the reply and pics -rm

[rmhurley]

Ah Mark MCM you read my mind re: s bend vs straight stays, and must have replied before I finished typing. I would agree that every bike would be a little different, but it seems like for the most part, most modern bikes are going to place that exit point in a functional threshold to work with MOST of the big brands, MOST of the time. Klampers by design are certainly an outlier here in terms of where the cable meets the caliper. The design does lend to their power but at a cost in some set ups it would seem.

I guess whether or not they fit has mainly to do with how far exactly the cable exit port is from the brake caliper? Considering that is not generally a detail listed in manufacturers spec pages, Im still curious if anyone has used them with success on an OPEN UP, or any other brands/models I listed in the original post.

[slowpoke]

Originally Posted by rmhurley

Do you think that the bend in the last few cm of the cable makes any difference to the quality? From my experience, the Klampers could lose a little bit of power and still have plenty to spare so i wouldnt worry so much about that aspect, but I do tend to get my bikes dirty and after a little while i wonder if the bend in the cable might get a bit sticky.

That bend in the photo seems like it's the source for a significant amount of friction and wear on the housing.

If you're looking at a new custom and want to use Klampers and maybe hydros in the future, then maybe split the difference and ask the builder to create the exit hole on the underside of the chainstay a few inches away for a gradual bend. This way you can route the Klampers on the outside, or hydros on the inside.

[.RJ]

Originally Posted by rmhurley

Do you think that the bend in the last few cm of the cable makes any difference to the quality?

I have honestly not noticed anything. The brake feels great and not really any different from the front, which is a straight shot.

I dont feel like this introduces significant friction or housing wear - the bike is now 2.5 years old and I havent changed the brake housing.

So while I wouldnt ever say this is advisable, in practice, its totally fine. One option you might want to consider is moving the cable exit further toward the BB.

[rmhurley]

Slowpoke, I would agree with a custom maybe anything is possible but at the moment, Im more looking forward to an off the shelf frameset where I would be able to use components I already have. I have a set of Klampers on one of my bikes and they are great even if a little heavy. Most of the bikes I am looking at are carbon and all with internal routing. If I did go with one of those and the klampers didnt work out I would likely be shelling out quite a bit more for a whole new brake set up and maybe drivetrain.

[jpsawyer23]

Awhile ago I setup a Open Wide with Klampers and Yokozuna housing. The bend coming out of the stay was too much for the Yokozuna housing and created tons of drag. But to get around it I ended up running the Yokozuna housing through to the BB and then from there using link style housing and a double sided ferrule to join the two. With the link housing the bend was fine and didnt create any extra drag. You could do this with standard brake housing or the Jagwire compressionless as well. And of course you can run not Yokozuna all the way, but I do think it really is the best and makes a huge difference over the other options.

[tellyho]

Swap them for some Growtacs - arm is on the inside

[rmhurley]

I have heard of combining different housing types in the same cable run. Not a bad idea and also like the idea of simply replacing the rear with a growtac. I have heard only good things and the location of the cable connection seems totally compatible with more or less any cable guide location. Thanks for the input!