Growtac Mech Disc

[NHAero]

Any more updates on the Growtac brakes? Mostly interested in the comparison to Shimano hydros - Ultegra and Dura Ace.

[tellyho]

If people are looking for a Spyre upgrade but don't want to shell out for Growtac, TRP Hy/Rds are a good compromise. Just made this switch myself and they are MUCH better than the Spyre. I'm imagining the JuinTech are similarly good; Hy/Rd can be had a little cheaper I think. Also TRP's support is outstanding.

[carlucci1106]

I like a light actuation feel. I'm stoked to try some Growtacs on a build I am doing for my friend's new bike, that I have here in the box. The way Campagnolo rim AND disc feel, as well as Shimano rim brakes, is the baseline. I have tried HY/RDs on bikes I've worked on and built, and they always fee "heavy" at the lever. Compressionless housing and other tweaks alleviates this to some degree? How about the pull ratio on the levers? I believe I tried them with Shimano levers (which have relatively long cable pull).

[joeminglin]

Anyone using these with Campy levers 11 or 12spd?

[gcartelli]

I've been using them for about 4000 miles, on 140 rotors. they've been amazing, I'm not in a descent heavy area though. There was one sketchy switchback on some mule roads that had me locking up but 1) that was early into my disc experience and they've been flawless for everything else.

[NHAero]

Originally Posted by gcartelli

I've been using them for about 4000 miles, on 140 rotors. they've been amazing, I'm not in a descent heavy area though. There was one sketchy switchback on some mule roads that had me locking up but 1) that was early into my disc experience and they've been flawless for everything else.

Do you have comparable experience on hydros, and how they rate vs. hydros?

[gcartelli]

Originally Posted by NHAero

Do you have comparable experience on hydros, and how they rate vs. hydros?

I've not, unfortunately. Have been wholly mechanical. If you're running 160 rotors and prefer mechanical and the weight savings, just go for it though. I don't think you'd have any regrets, (location/terrain somewhat depending).

[jpsawyer23]

I have been using them with the TRP drop bar levers and they feel amazing. Those levers are really some of the best though.
I did the switch from shimano ultegra hydraulic brakes though and dont notice much in the way of performance or lever feel. The pull is surprisingly light for a cable actuated brake. IMO the only downside vs. hydro and this setup is you have to adjust the brakes occasionally as pads wear, but thats normal for any cable actuated brake and is very easy on these.

[ewwhite]

I just received a set and I'm excited to get everything installed and running:

https://www.instagram.com/p/CpTrWRUvBui/

[NHAero]

Yesterday I pulled the R8020 Ultegra mech/hydros off the Habanero and replaced with R8000 mech/mech shifters and the Growtacs. The box includes everything needed for just about any installation, there are a lot of extra bits. For example, there are two sets of stiff, compressionless +/-5.5mm OD housing, and two shorter sets of typical brake housing (to use on drop bars where the initial bends are tight) and I built up my 55cm frame using just one set of the housings. There is a connector fitting to join the two housing types. There are something like five sets of flat mount bolts in different lengths, and a bunch of different housing caps.

I found them very straightforward to install and the directions clear. It's super easy to align the caliper properly and to adjust pad clearance (each side separately with a 3mm hex wrench.) As noted, the cam action is variable so you do need to pay attention to set up to stay out of the “danger zone” and I know I'll need to get into the habit of looking at the indicator as the pads wear.

I found the instructions confusing at one point, which is around the setting of the actuator arm to avoid the danger zone. The instructions indicate that the cable tension adjuster affects this setting but it doesn't appear that way to me. Where the actuator arm is depends on pad clearance and once clearance is minimized (is there an instance where this isn't desirable?) the actuator arm max throw is determined. I'm not saying one couldn’t set these up poorly, but rather that if you follow the directions and want minimum pad clearance and minimum brake lever throw it would be hard to screw it up.

Once everything was installed, I went out to bed the pads in. I did maybe ten iterations of getting up to 15-20 mph and applying the brakes to scrub about 10 mph off. After this, the brakes function very well. The stock pads feel effective and they are not grabby but they have good stopping power. Then I swapped in a new set of MTX ceramic pads into the front brake and did the bedding again. Unlike when I did this with my Shimano DA hydros with K02Ti pads, the MTX didn't have a noticeable bump in braking power, so I swapped back to the Growtac pads.

On dry pavement it's easy to break the rear tire loose and it's easy to get a stoppie with the front brake. They aren't as powerful as Shimano hydros IMO, but they're good enough that I can brake from the hoods with my small, somewhat arthritic hands. I only rode 5-1/2 miles bedding in the pads and testing the brakes, so this is a very preliminary evaluation. We have some decent weather coming this week so I hope to be able to give these a more thorough test on the road.

My motivation is that I intend this to be a travel bike and I believe using mech discs will be less prone to hassle, so if they work well enough that will be good!

The last photo shows the connector between the normal housing and the stiff compressionless housing. This housing and the Growtac brake caliper gives a nice stiff feeling at the lever, which I quite like but others might have different preferences. The lever feel is stiffer than the hydros these replaced.

[mjmcgee]

If you've been looking at picking up a pair, Velo Orange just sent out an email with a 30% off code, and it works on these.

SPRING30 is the code.

Mine are incoming

[v531xc]

I just came to post about the VO code, too. I snagged a pair of these with the code, too

[m_sasso]

OK, thanks for the code post but just sell me your Juin Tech gt-f/Yokozuna Ultimo callipers when you pick up these.

[reuben]

I can't believe I just ordered a pair of disc brakes, but I did.

[m_sasso]

Originally Posted by reuben

I can't believe I just ordered a pair of disc brakes, but I did.

Just keep saying acceptance and like are two different levels! Lots of sacrifices made to ride somtimes.