linberl

I need to install a bracket for an accessory on the front wheel of my Bike Friday pakiT. It attaches behind the dual pivot caliper brake as well as at the forks. My current brake, a shimao 105 dp caliper, sticks out too far from the mounting hole to fit the bracket, which essentially goes "on top" of the brake. The brake is about 1.75" long from the mounting hole, it's very robust and also quite thick. I need a dp caliper brake (of good stopping power) that will work with my existing Tiagra 4700 super SLR flat bar levers, but that is not much
wider than 1.25" from the mounting hole. Are there any dp calipers known to be fairly slim, low profile, that might work? I've got various pivot bolt extensions but that doesn't
solve the problem of the fixed depth of the bracket I need to install which mounts flush to the frame hole, behind the caliper brake.

rhenning

My first thing would be to call BF and ask them what they do to solve this. DP brakes fit right on my 1994 Pocket Rocket when I up graded. Roger

linberl

My brake fits fine except to add the mount for my friction drive....which needs a brake that is 1.25" or less front to back. The Shimano 105 is much longer. It's not really a BF
issue at all, it's an issue with my friction drive mount.

nfmisso

Seems like you are trying to attack the wrong side of the issue - what can be done to adjust the friction drive so that it is further from the fork?

Pictures required.

linberl

Yes, except...this is a commercial unit, not a DIY, and I bought it specifically because I'm not skilled enough to make my own. The bracket has a 1.33" extension so the caliper brake needs to fit pretty much within that length. There is a rear mount option but I really would prefer to NOT do that, so that's why I am trying to find a front brake that will fit the
supplied bracket. I do not have a picture of the one that works with caliper brakes but I do have a pic of the bracket for v-brakes; it's similar but there are special fork attachments for
the leg attachments for the caliper model.

linberl

Ok, so I have looked at millions of pictures of caliper brakes and read tons of reviews. While it looks like these might fit in terms of my bracket needs (I will have to hit a shop
to actually measure) I don't know if the will work in any way with my existing levers. Can I use Campagnolo Potenza brakes with Shimano BL4700 flat bar lever? I
would only be changing out the front brake; I will leave the rear the 105+BL4700 combo. I know Campy doesn't have a quick release, but I don't really care - it's a front
wheel so rare to flat, and I usually patch 'em while still on the bike anyway. I am mostly concerned about compatibility with the brake pull (something I don't completely
understand) and my levers have multiple adjustments for canti/v brake/caliper but I don't know if the Super SLR will be an issue. Any one know?

The other brake that looks like it might fit is Shimano Dura-Ace BR-7800. Would that be compatible with my BL4700 lever?

fietsbob

I assume you found the picture not your bike , given I see V brakes ,

Perhaps vacate the front of the fork and mount the brake on backside , and your motor on the front..?


You do have several frame builders in the area , maybe modify the steel fork

replace the front wheel with a drum brake hub, and vacate the top of the fork crown entirely.

buy a disc brake fork from bike friday, etc.... etc.

linberl

I tried putting the brake inside the fork but it interferes with turning :-(. The least expensive thing for me to do to make it work is install a caliper which fits in the bracket even if I also have to get a different lever (I guess the super slr lever doesn't work with everything). I'm pretty sure a single pivot would fit and would consider a good one, also it looks like the FSA gossamer/gosammer pro brake would fit - not sure if I could use my Shimano BL4700 lever with it though. I'm getting the friction drive Tuesday so I am going to wait and actually put it on the fork so I can measure it out exactly. I can push the bracket a little bit but there are definite limits. The 105 is a great brake but it is definitely kind of "fat" in structure. Once i know the exact amount of space I have to use I will probably go hit up my LBS and take a tape measure and just measure all their caliper models, lol.

I just thought some caliper brakes might have been known as narrow profile....

Andrew R Stewart 

As the dimension you speak of isn't really an aspect that most component makers or their customers care about it should be no wonder that this spec isn't listed anywhere. I'll also speculate that this spec falls within a narrow range for most dual pivot bolt on calipers.

Of course the OP knows that installing and using an auxiliary power unit will void any warranty and pretty much stack any legal situation against you. Andy

linberl

I know it's not a standard statistic, otherwise I would have been able to look it up myself, lol. I just was hoping someone had some experience and noticed the differences. From images, it looks to me that Sram brakes are not as thick, but I'll have to get into a bike shop to confirm. Easy enough to change one caliper and one lever. As to the motor, my bike manufacturer is aware of what I'm doing and they are totally on board with it =).

Andrew R Stewart 

I'm glad the manufacturer says they're good with your mods. I hope that is reflected in their written warranty. Good luck. Andy