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huskerdont
04-26-2016, 07:54 AM
So, my new Masi CX Comp comes with the disc brake mounted on the chain stay in front of the seat stay. I've noticed that my foot occasionally hits the caliper while pedaling. While grinding a few miles out the towpath yesterday to lengthen the ride home, I eventually clued in that it was getting harder and harder and I was going slower and slower, even though I didn't *think* I was tired. Dismounted and checked everything out, and the brake was tight enough that it was difficult to turn the wheel by hand. The barrel adjuster was most of the way out from my foot hitting it.

There are mounting holes behind the seat stay, but these are for racks, not a brake. Apparently there's no adapter that can be used to mount it there such as on my Soma mountain bike.

So, any ideas on preventing this? I have a lower profile pair of shoes that hits it less so that will help to use them for this bike. I might put some tape on it as a temporary fix, but other than gluing the thing down, that's all I got. It's too late for footbinding.

bentbike33
04-26-2016, 09:54 AM
So, my new Masi CX Comp comes with the disc brake mounted on the chain stay in front of the seat stay. I've noticed that my foot occasionally hits the caliper while pedaling. While grinding a few miles out the towpath yesterday to lengthen the ride home, I eventually clued in that it was getting harder and harder and I was going slower and slower, even though I didn't *think* I was tired. Dismounted and checked everything out, and the brake was tight enough that it was difficult to turn the wheel by hand. The barrel adjuster was most of the way out from my foot hitting it.

There are mounting holes behind the seat stay, but these are for racks, not a brake. Apparently there's no adapter that can be used to mount it there such as on my Soma mountain bike.

So, any ideas on preventing this? I have a lower profile pair of shoes that hits it less so that will help to use them for this bike. I might put some tape on it as a temporary fix, but other than gluing the thing down, that's all I got. It's too late for footbinding.

Try one of these on the left side?

http://hostelshoppe.com/KNEESAVERS-Pedal-Extenders-174591/

huskerdont
04-26-2016, 10:16 AM
Try one of these on the left side?

http://hostelshoppe.com/KNEESAVERS-Pedal-Extenders-174591/

That might work. I used something similar many years ago converting a 1965 Schwinn crank to modern pedals. Thought of them as an adapter, not something to move the foot over. I'm going to give them a try. Thanks!

dkel
04-26-2016, 10:19 AM
Changing your Q-factor can have physical consequences for your knees, so be sure to listen to your body as you ride those.

huskerdont
04-26-2016, 10:22 AM
Changing your Q-factor can have physical consequences for your knees, so be sure to listen to your body as you ride those.

Definitely. I have enough knee problems as it is. Post-surgery, seems there's always a new thing going on in there I need to pay attention to.

dkel
04-26-2016, 10:23 AM
You could also use shorter crank arms, if the overlap is slight. This also has effects in bike fit and pedaling efficiency, though. It's possible a different caliper would give the desired effect; that change wouldn't effect your riding position at all.

huskerdont
04-26-2016, 10:29 AM
You could also use shorter crank arms, if the overlap is slight. This also has effects in bike fit and pedaling efficiency, though. It's possible a different caliper would give the desired effect; that change wouldn't effect your riding position at all.

I think it's too much overlap for shortening 5 mm to work. I might look into getting some BB7s instead of the Promax ones that came on stock if other solutions don't work out. The Kneesavers seem like a cheap enough thing to try and toss if it doesn't work (knee or hip pain or pedals hitting on turns). In the meantime, first thing I'll do is a long ride with the other shoes. Their heel is much narrower and smoother so doesn't hit nearly as often and may not turn the barrel.

Thanks to all for the ideas.

bentbike33
04-26-2016, 11:26 AM
You could also just remove the barrel adjuster from the brake caliper, as long as you have one on the lever.

Although I thought most mechanical disk brake manufacturers recommended against using the barrel adjusters at all in favor of moving the pads.

dkel
04-26-2016, 12:43 PM
You could also just remove the barrel adjuster from the brake caliper, as long as you have one on the lever.

Although I thought most mechanical disk brake manufacturers recommended against using the barrel adjusters at all in favor of moving the pads.

This is a really good point. I don't think my BB7s or my Spyres have barrel adjusters at all.

huskerdont
04-26-2016, 01:02 PM
This is a really good point. I don't think my BB7s or my Spyres have barrel adjusters at all.

It is a good point. I looked at the BB7s on my mountain bike last night and there was no barrel adjuster.

hozn
04-26-2016, 05:17 PM
Spyres have barrel adjusters. Though it is unlikely that your foot would hit it on a Spyre.
http://uploads.tapatalk-cdn.com/20160426/1ab2d94954abfbffca92eaec594b3567.jpg

Barrel adjusters don't make so much sense on the BB7 which is not a dual-piston design (I.e. only one side of caliper moves).

I love the barrel adjusters on the Spyres for pulling in the pads (compared to the bb7 adjustment wheels). In general, I think the Spyres are better brakes.

Of course, now that I put hydros on my commuter, I will probably never go back to mechanicals.

dkel
04-26-2016, 08:29 PM
Spyres have barrel adjusters.

11627

Yeah, I probably should have known that. :p

huskerdont
04-27-2016, 07:53 AM
What I have here is a case of design envy.

11629

I'll never go back to hydraulics, but I might replace with BB7s eventually. Can take the one off my mountain bike and see if it clears any better. The problem may not be solved with a different model because of where it mounts. I'll likely remove the barrel adjuster, but my foot will still hit it and eventually could cause damage or wear.

hozn
04-27-2016, 09:11 AM
I'll never go back to hydraulics, but I might replace with BB7s eventually. Can take the one off my mountain bike and see if it clears any better. The problem may not be solved with a different model because of where it mounts. I'll likely remove the barrel adjuster, but my foot will still hit it and eventually could cause damage or wear.

Note that a MTB BB7 is not the same as a road BB7. If you just mean to check the clearance, that is probably reasonable; I don't know if the calipers are actually shaped differently (but cable pull / actuation is different).

What happened to steer you away from hydros? I've always been a big fan of mechanicals on road or MTB, but that was mostly because I'd never tried hydros. [Powerful] single-finger braking from the hoods has me hooked. And the ergonomics of the SRAM hydro hoods are much better for rough stuff. The braking is, in short, significantly better. That said, I do hold that hydros are a lot more setup work than mechanicals. Time will tell how much maintenance work they require. If I have to bleed my brakes more than once or twice a year, I might rethink the value proposition.

In related news, I might have some Spyres for sale shortly ...

vvill
04-27-2016, 09:57 AM
I've always been a big fan of mechanicals on road or MTB, but that was mostly because I'd never tried hydros. [Powerful] single-finger braking from the hoods has me hooked. And the ergonomics of the SRAM hydro hoods are much better for rough stuff. The braking is, in short, significantly better. That said, I do hold that hydros are a lot more setup work than mechanicals. Time will tell how much maintenance work they require. If I have to bleed my brakes more than once or twice a year, I might rethink the value proposition.

Good to hear the SRAM hydros are working well! I have my heart set on hydros for my next road/CX/gravel/adventure bike, whenever that is, and I'm thinking SRAM. Mech discs are great in that they solve all the basic issues of rim brakes (riding in the wet and no rim wear) but I agree that hydros are still a significant improvement. I'm hoping that bleeding will only be required at most once every year or two. I'll never upgrade the BB7s on my 26" beater bike though - they work perfectly for their purpose.

huskerdont
04-27-2016, 12:09 PM
The hydraulics on my old Gary Fisher Tass went on me (a leak). Bought the fluid and everything to fix and just didn't like fiddling with it so converted to BB7s. I didn't notice any difference in braking ability between the mechanicals and the hydraulics, so I was happy to switch. (Note that it took me a while to notice my brakes were rubbing on that ride on the towpath, so I may not notice subtle differences very well.) The braking with mechanicalis is so much better than with standard brakes, I'm happy enough with them.

huskerdont
04-27-2016, 12:11 PM
Note that a MTB BB7 is not the same as a road BB7. If you just mean to check the clearance, that is probably reasonable; I don't know if the calipers are actually shaped differently (but cable pull / actuation is different).

Good to know, thanks.

vvill
04-27-2016, 12:20 PM
The hydraulics on my old Gary Fisher Tass went on me (a leak). Bought the fluid and everything to fix and just didn't like fiddling with it so converted to BB7s. I didn't notice any difference in braking ability between the mechanicals and the hydraulics, so I was happy to switch. (Note that it took me a while to notice my brakes were rubbing on that ride on the towpath, so I may not notice subtle differences very well.) The braking with mechanicalis is so much better than with standard brakes, I'm happy enough with them.

I wasn't bowled over by the hydros on my 29er (Shimano SLX) but they do feel more powerful (easier with one finger braking) and a little less grabby than mechanical discs. Not really a game changer though. The TRP Hylex brakes on my SSCX though, those are what won me over to hydros. I do think perhaps that road BB7s were never really designed from the ground up for road bikes, so the improvement from MTB mech => hydro was less pronounced than that for road brakes.

hozn
04-27-2016, 12:58 PM
I will say that my mechanical (BB7) setup on the MTB was really good. Using good housing, etc. the difference in stopping power and even lever feel was pretty close to the SLX hydros I have now. So I agree that on MTB it may not be a huge difference. That said, the SLX definitely stop with [a lot] less finger force and the modulation is better. So not night & day difference, but was well worth it for me. -- And that's saying something, since that was my first experience with disc-brake bleeding and it was a learning experience, to say the least.

On the road, however, hydraulics make a very substantial difference, in my experience. For mechanicals, I have used BB7s and Spyres. Spyres are a little nicer (once you swap out the TRP rotors), but neither provided the power and crisp engagement of BB7s (or certainly hydros) on the MTB. And lever would always end up pretty close to the bar when I needed full braking. Single-finger braking was a tall ask on the road -- and really not a good option from the hoods, both for the force needed and the fact that the engagement was so close to the bar that my other fingers gripping the hood would be in the way of achieving full braking. On my road bike I run TRP Spyres with Yokozuna Reaction housing, which is really expensive but gives the best feel (i.e. is most compressionless). On the commuter I was using Jagwire Ripcord which despite being great on the MTB always felt spongy on the road levers.

Anyway, my general dissatisfaction with disc braking performance on the road bikes has been completely addressed by the SRAM Force 1 (L) / S700 (R) hydro setup I have now. Braking is on par with MTB hydro performance. Full braking happens long before levers are touching the bar -- and swapping wheels [with the same hubs] seems to auto-adjust as I was hoping it would (w/ mechanicals I had to run them a little more open since even with same hubs and rotors there would be tiny spacing differences). Only downside I have yet experienced (besides the fact that they have to be bled) is that there is some rotor rub noise sometimes after torquing the front wheel (e.g. out-of-saddle climbing); it goes away shortly as the pads auto-correct. Or can be cured by hitting the brakes briefly. I imagine this would not be an issue if I had a thru-axle fork.

To be clear even the "inferior" braking performance of BB7s or Spyres is better than rim brakes. (And vastly better than rim brakes on carbon.)

huskerdont
05-10-2016, 08:51 AM
After two commutes using a lower-profile shoe, my foot hasn't hit the barrel adjuster once, so perhaps I don't need to remove the adjuster. As long as I can remember to use the right shoes.

Vicegrip
05-10-2016, 09:02 AM
Back the adjuster all the way out and wrap 1 or 2 turns of Teflon plumbers tape around the threaded portion. Reinstall and done. The adjuster will still turn when needed but not as easily.

huskerdont
04-18-2017, 07:38 AM
Reviving because the solution turns out to be to replace the Promax brakes with TRP Sypres.

The Masi still has the Promax, but I had the same problem on a Cannondale Synapse with Promax brakes. Put on some Spyres, and the problem is gone. The Promax brakes jut out past the chainstay, but the Spyres sit nice and pretty over top of the tube. So they're a little bit lighter, they don't get hit by my shoe, and they actually do the job they were designed for. Will replace on the Masi too once funds become available.