Growtac Mech Disc

[XXtwindad]

Originally Posted by NHAero

I'd think less for you than for me. On the performance side, I expect hydraulics will remain the gold standard. Also, you, Lavi, and Donevwil are all larger humans than me, so sheer braking power may matter more, and it's possible you might detect more of a difference between braking systems than a 140 pound rider.

On a day to day basis, on the occasions I put the bike in the car, I have to remove the front wheel and remember to put the spacer in between the pads so I don't accidentally hit the brake lever and pop the pistons. On a longer term, I don't have to worry about bleeding, and there is a lower chance of the pads getting contaminated by the brake fluid (mineral oil in my systems). So I'm not urging everyone to run out and buy these, we each have our own priorities.

Thanks for the concise answer. Much appreciated.

[reuben]

Originally Posted by NHAero

On a day to day basis, on the occasions I put the bike in the car, I have to remove the front wheel and remember to put the spacer in between the pads so I don't accidentally hit the brake lever and pop the pistons.

As a new user of mechanical disc brakes, can you explain this to me? I don't get it.

[Jaybee]

Originally Posted by NHAero

On a day to day basis, on the occasions I put the bike in the car, I have to remove the front wheel and remember to put the spacer in between the pads so I don't accidentally hit the brake lever and pop the pistons.

Originally Posted by reuben

As a new user of mechanical disc brakes, can you explain this to me? I don't get it.

What NHAero is describing is a hydro brake phenomenon. If you don't have a rotor or other spacer between the pads and the lever is pulled (usually a lot, and repeatedly), the pistons can close on each other. It's a relatively minor deal, just get a tire lever and push them back, but it can be annoying.

You, a new user of mechanical brakes, won't see this.

[XXtwindad]

Are mech discs lighter? If so, by how much?

[CAAD]

Originally Posted by reuben

As a new user of mechanical disc brakes, can you explain this to me? I don't get it.

If you squeeze the lever of a hydraulic brake without a rotor in place the piston can get pushed out and either pop out of the caliper (many lever pulls for that to happen) or push the pads out enough where you will have to spread the pads back open to fit the rotor/wheel back in.

I like mechanical brakes for their simplicity. I do travel a lot and the bike is in the car or broken down in a bike bag going on a flight. The last thing I want to do is worry about bleeding a mushy lever at my destination. I worked at a bike shop, many customers showed up with that exact issue when in town for an event. With a mechanical setup, I can get a brake cable literally anywhere I travel.

[NHAero]

Originally Posted by XXtwindad

Thanks for the concise answer. Much appreciated.

I like simplicity. When hydros appeared, I said I would never have hydro discs on a bike. I was a motorcyclist for years and so had experience with working on hydros, it wasn't theory. Then in 2015 I got the Pivot FS29er used, with XT hydros, and they were so much better on a MTB that I was in. I had BB7 Road cable brakes on my Anderson, and I think Avid never got the road versions right. I still have BB7 MTB calipers on my Big Dummy and on the Litespeed, and with compressionless housing and flat bar levers they work very well. I've never felt the need to try Spyres or Juintechs or Klampers.

The Klampers apparently function well but have poorly design cable routing IMO, are heavy, and weigh a ton. The Growtacs made sense to me, I watched the usual Youtube reviews and decided to go for it, because on a travel bike where I will be removing the calipers from the frame and especially the fork I will avoid the hassle of re-setting the calipers so there is no pad rub. It's super easy with the Growtacs. And I won't need to worry about some weirdness with air in the system 3,000 miles from home, or oil on the pads.

That said, I've had hydros on the Strong and now the Bingham without any incident for a couple of years and with excellent performance. Part of this is I like to try new things when they make sense to me.

Einstein said, things should be as simple as possible, and no simpler. I like discs for bikes that can get ridden in other-than-dry conditions, so I'm willing to put up with that level of added complexity, but if cables can work, that does simplify things. i recognize that the Growtacs have a variable cam actuation and I will need to pay attention to pad wear, but my experience is that I get >5,000 miles out of a set of road bike pads, so this isn't exactly an everyday occurrence.

[NHAero]

Originally Posted by XXtwindad

Are mech discs lighter? If so, by how much?

I didn't do a good job at this when I swapped on the Habanero. My intention is to swap them on the Bingham (which has Dura Ace so pretty light) and weigh the whole bike before and after if I can remember in my tiny brain to do so. guessing there will be a slight savings because I think the DA hydro levers are maybe 100-150g more than the mech levers. The DA calipers are likely a bit lighter than the Growtac calipers.

[CAAD]

Originally Posted by XXtwindad

Are mech discs lighter? If so, by how much?

Red 22 mechanical hydro shifter, caliper, and hydro hose is around 378g each. So around 756g total from and rear.

Red 22 full mechanical shifters 280g for the pair, Growtac calipers 170g = 450g front and rear. Plus cables 100g +-?

Red AXS is around 750g for the pair, hoses, shifters, and caliper.

[NHAero]

Originally Posted by CAAD

Red 22 mechanical hydro shifter, caliper, and hydro hose is around 378g each. So around 756g total from and rear.

Red 22 full mechanical shifters 280g for the pair, Growtac calipers 170g = 450g front and rear.

Red AXS is around 750g for the pair, hoses, shifters, and caliper.

The housing and cable is surprisingly heavy, so with luck I'll have some comparable weights.

[ssb94]

I was intrigued by these until I saw the price... Especially compared to Spyres (I feel the same about Klampers). Serious question for those who have gone this route: if you're going to spend this much, why not move to hydro? Is it all about shifter ergonomics?

Edit: feel free to ignore this, just saw all of the answers above 😅

[donevwil]

Originally Posted by XXtwindad

I haven’t read through the whole thread, but I’m intrigued. For someone (me!) who doesn’t bike pack, rarely does centuries, and is not mechanically inclined, what is the advantage of Growtacs or cable actuated disc brakes?

Only one advantage for me, I have one disc bike and it's, as are all my road bikes, Campy 10. Cable actuated discs are my only option (well, other than a very expensive upgrade). My current Yokozuna Motoko's are on par with a well setup pair of cantis, certainly no better. Since it's hilly around here and my total rig weight approaches 300# when commuting, I'm hoping these Growtec's are an improvement.

For comparison, my wife's old MTB has 9 spd XTR with hydraulic discs. These hyro discs must be near Shimano's first generation and most in the know recommend avoiding them for various reasons, but the brakes are far more powerful and have better modulation than my Yokos.

[tellyho]

Originally Posted by XXtwindad

I haven’t read through the whole thread, but I’m intrigued. For someone (me!) who doesn’t bike pack, rarely does centuries, and is not mechanically inclined, what is the advantage of Growtacs or cable actuated disc brakes?

No bleeding. No contaminated pads / rotors, by extension. Plug-and-play. Coming from just having bled all my mtb discs, mechanical calipers are looking better and better.

[m_sasso]

Originally Posted by tellyho

No bleeding. No contaminated pads / rotors, by extension. Plug-and-play. Coming from just having bled all my mtb discs, mechanical calipers are looking better and better.

No heavy, clunky looking, leaking and shaped master cylinder horns sitting on my handle bars I am forced to grab when I want to slow down

Recycle your mechanical brake/shifters that came with your last group set without having to purchase hydro brake shifters to get the supposed many advantages of disk brakes.

Not a fan of hydro disc brakes, hybrid hydraulic, cable actuated, OK much more rational engineering for a bike!

[litcrazy]

As I’m prepping to bleed a set of elixirs, i wanted to get the early adopters take on whether they’d put these on a mountain bike with short pull levers.

I’m running spyre’s with short pull ird levers on my rigid wily 29er with 160mm rotors. Less fuss than the BB7s they replaced (so far).

What do you think of doing the same with these growtac with 160mm rotors? Any reason not to run these mountain?

[litcrazy]

Because if this is just about a cultural taboo like not riding mountain in bibs with chamois cream, I’ve already crossed that line.