Winfried

Hello,

A friend of mine has a Genesis Tour De Fer 10 with drop bars, but isn't very happy with the Promax DSK-717 cable disc brakes: She doesn't find them strong enough, and the pads are a bit of pain to change.

I'm no expert, and was wondering if it'd be possible to replace the (front) brake with a hydraulic brake instead in the same financial ballpark.

The brake lever is a Shimano Sora ST-R3030 3 x 9 Speed, the front derailleur is a Shimano Sora FD-R3030, and apparently it's a post-mount with a 160mm disk rotor.

Thank you.

delbiker1 

I suppose it is possible, but not a simple, low cost change. Pretty sure you would have to switch the whole the shifter/brake lever components as well as running hydraulic lines to the new brakes calipers. Has someone that knows what they are doing tried to adjust the set up of the Promax brakes. I am not familiar with the Promax, but I do have mechanical Avid 7 brakes. They can be a pain to get right, but work really well with the proper set up.

jimc101

Possible, perfectly, but very expensive, but would budget €700 minimum if you can do it yourself, €8-1200 if you need to get a LBS to do it, add to that, availability for road hydraulic discs has been always been poor on the aftermarket, would look places like Rose if you can't source them in FR

The first issue is the bike has 3x at the front and 9 on the back, and no one makes a 3x hydraulic shifter (STI) or 9 speed, so you have to go 10x2 at a minimum if you wanted to go full hydraulic braking, you would need to get a full set F/R shifters/brakes, say (ST-4725-R (shimano.com), 2x crank, and 2x FD, and probably a new wider range cassette and longer cage RD and chain to make up for the gearing lost going to 2x you may need to look at a new rear wheel if your current can't take a 10 speed cassette.

There are a few options you could look at before going the hydraulic route, the cheapest would be to replace the stock pads with metal/Sintered(same thing) pads, to replace the the stock resin pads which normally come with calipers. Next would suggestion would be to replace the l disc rotors, say with Shimano (and decent Shimano, not ones which are for resin pad only, like the RT56) and if that doesn't improve the braking to what is needed, the calipers, as per delbikeri, personal preference would be Shimano R317/R517, but Avid BB7's do the same job.

Winfried

Thanks, that's what I feared :-/

I'll investigate those options.

jimc101

Would really look at the pads and maybe rotors, I had high wear, leading to poor breaking using stock resin pads on Shimano CX77 brakes ( up to a point that I needed to stop and adjust after every significant decent), replaced them with Sintered pads, and haven't needed to adjust anywhere near as much since.

Pads, are consumables, so your going to be replacing them at some point, so cost really isn't an issue with them.

HillRider

I've no experience with Promax brakes but most of what i've read hasn't been very flattering. I do have a new bike with TRP Spyre mechanical disc calipers and Shimano 160mm SM-RT800 rotors and they work very well. They are not "power brakes" but they are at least equal to good rim brakes in lever effort. They would be a relatively low cost change for your friend as all you would need to change is the caliper and perhaps the rotor as they will be compatible with the existing brake levers.

Winfried

We'll check if those rotors accept metal pads, along with a possible upgrade to TRP Spyre caliper + Shimano SM-RT800 rotor.

--
Edit: Looks like the SM-RT800 uses Centerlock, while the rotors on the TdeF uses a six-bolt holder

But its me 

Spyre brake swap would be the most cost effective in my mind. You get dual pistons and easily replaced pads, while not going through the whole group swap/upgrade to hydraulic. I run Spyres on my Soma Saga and love them. Mind you, I have never used hydraulic brakes, so take that for what it’s worth.

HillRider

Yes they do but Shimano sells equivalent rotors with 6-bolt mounting.

Winfried

Thanks. I'll check 'em out.

"I’ve been commuting full-time on the Soma for a few months now and my feeling about the Spyres hasn’t changed since the first shakedown ride— they are simply the best mechanical disc brakes I’ve ever used. It’s a pretty thin market — after discarding some extremely low-end options I’ve ridden over the years from Hayes and Tektro, you’re really just left with the offerings from Avid and Paul. I haven’t hopped on the Klampers, but the Spyres have so far been more powerful and provided better feel than any set of BB7s I’ve experienced, and for a comparable price."
https://medium.com/@AdventureCycling...s-1500e7e9dc03

jimc101

A question was asked, and an answer for that question was given, no that answer may not have been what you or the OP wanted to hear, but it was a realistic answer, given the original question, really don't understand why your implying it 'hasn't been very flattering' the OP's bike given the specs makes is a very poor (cost wise) choice to fit hydraulic brakes to, due to needing a complete drivetrain/rear wheel replacement, in addition to the brakes, .

Can you give any alternatives, other than the multiple cheaper options/suggestions already given?

mack_turtle

TRP Spyres or SRAM BB7 Road brakes would be an improvement and would be an easy swap with the existing brake lever/ shifters. Yokozuna, TRP, Juin Tech are hydraulic brake calipers that are cable-actuated that would also work. Paul Klampers are another choice if you have the $$$ for them.

even cheap mechanical calipers can usually be quite powerful if set up correctly, but cheap calipers seem to make that more difficult.

veganbikes

I would replace the brakes with something like the TRP Spyres, you will get a bigger pad and dual piston actuation. Those tiny BB5 pads and other similar tiny pads just don't give you much real estate to stop with. The TRP pads are also Shimano compatible and are used by probably 50+ different brakes (From Shimano and TRP/Tektro) so there is a really good chance of finding pads. not that BB5s are exceedingly rare but I see them a lot less then Shimano and Tektro.

More importantly I would replace the cables and housing. You want housing that is compressionless and you want a cable that is slick, smooth and stainless. I would recommend Jagwire's Elite Link kits which come with everything you need. I will say with disc brakes you may need some extra "beads" so you might especially if you have a hybrid or MTB with cable brakes is get yourself the mountain kit and buy some road cables and now you have an extra set of cables for those other bikes.

I would also get good rotors if you have 6 bolt the Shimano Deore XT SM-RT86 is a good choice and with good fresh pads from one of the Stops (Kool or Swiss) will help quite a bit. Larger rotors can also help but you will need the right adaptors for it assuming they can fit.

If you really want Hydro discs TRP HY/RD is you best option as it is cable actuated until the caliper where it switches to hydraulic braking so you don't have to swap levers and all of that which is expensive though honestly I the Spyres are just fine and dandy.

katsup

You can also try some cable hydro brakes that will let you use the same shifters. I'm using the Juin Tech R1, but I'd go with the 4 piston Juin Tech GT if I were to do it again. TRP also has one.

HillRider

What is your problem with my answer? Did you read all of it? The OP stated his friend wasn't satisfied with the current Promax brakes and wanted to know if fitting hydraulic brakes was a practical option. Several posters pointed out it would be a very expensive change and probably impractical. I offered a mechanical alternative that was cost effective and, in my experience, offered good performance.

Russ Roth

Rear wheel seems dramatic and completely unnecessary. 9 sp uses the same wheel as 10sp and Tiagra 4725 is a short reach hydraulic sti lever. It does require its own rear der and it would start making things expensive, not quite to the level stated since Europe gets much better pricing then the US but still up there but more like 500.00 which isn't horrible for what I consider a really decent group.

This is the real route I would go; I've done the Juin Tech on my wife's cross bike and will get some for her gravel bike. The TRP are slightly better due to the pads self setting as they wear down where the Juin Tech require cable adjustments to compensate for pad wear. The Juin are noticeably lighter and have a lighter action which is why I went with them for my wife.

Winfried

Thanks for the input. We'll try the different options mentioned in the thread, from better brake metal pads, and possibly all the way to cable hydro brakes.