Cycling in Sydney Australia
I'm modifying a (soon to be motorised) Yuba V4 cargo bike that will carry a couple of hundred kilos down some steep hills, so I want good brakes.
I can get the Deore XT BR-M8000 for about $60 below the Acera M395.
I'd love some thoughts from experienced riders.
I have disc brakes on my Yuba Mundo. I suspect that either of the brakes you mention will do the job perfectly well. If you can get the XT brakes for a good price, it's hard to beat them.
There are two critical things to make sure of with your disc brakes that, arguably, matter a lot more than which model brake you purchase:
I would also mention that you need to adjust your braking technique on a cargo bike. Normally, the front brake should be the dominant brake and applied first and for most of your braking. However, on a longtail cargo bike, with the loads involved and the wheelbase that means an endo simply will NEVER happen, you need to use the rear brake for 60%+ of the braking loads. This reduces the forces being imposed on the fork and headset while still giving you very effective braking because rear wheel lift is non-existant.
I was reading of people using 160 on the front and 200 on the back so because of my loads and hills and I thought I'll put a 180mm on the front and a 203mm on the back. Both being "XT-Saint RT86 Ice-Tech 6-Bolt" rotor. That sounds good to me, but is it?
When everything arrives, I'll do most of the install then take the Yuba to Glow Worm (my retailer) and pay them to look after the rear hose and give my set up the once over.
One other thing though is that I know I need Shimano adaptors but because I'm new to DBs I don't know what is what. I know I need adaptors front and back but which adaptors do I need. I know I'm looking for something that is 180, and something that is 203 but the rest is a blur. This page mentions
Shimano Mount Adaptor Front Post to Post,
Shimano XTR Mount Adaptor Rear IS,
Shimano Mount Adaptor Rear Post to IS 203mm,
Shimano Mount Adaptor Rear Post to IS and
Brand-X Disc Brake Adaptor - POST to POST
I reckon a 180mm rotor would be big enough front and rear.
Disc brake adapters are a royal pain in the arse on the rear of the Yuba, because the frame mounting is non-standard due to the size and shape of the frame tubes. I'll have a look at my bike tonight and let you know what I ended up using, but if you aren't familiar with disc brakes, I'd suggest you might want to let Glow Worm do the complete install.
Thanks again Adam.
s a good article isn't it? That's where I first saw the 160/180 suggestion to deal with the need for different braking back and front.
I like the idea because then, if I have a fairly inexperienced rider take the bike out, they don't need to remember to go harder on the back, than front. So there will be less chance of the bike going down in an emergency braking situation, injuring the rider and bike, and destroying $600 worth of produce and the lightweight coolbox that I've designed that will have to be rebuilt. Whether the inexperienced rider is me or some poor fella I've hired to help, it's something to avoid and I think the 160/180 is a great idea. But because everyone says 180mm minimum (which is what the V5 comes with) I figured better to step it up than down.
Do you see a downside to it?
Of course, it might not be doable anyway because the local distributor isn't sure if it would cold the frame warrantee for some reason. I suppose that 203mm might be a bit hard up front on the forks but I don't see how that would be a problem down back. Anyway. I was all excited and ready to order them after getting some feedback but now I'll have to wait to hear back from Yuba.
Thanks for offering to look at the mounts.
I doubt the 200 in the rear would overload anything, it's just whether there is enough room inside the frame. It should be fine. I'll check tonight.
I don't have a cargo bike but I do have a bike that carries cargo.
A couple of tours past I changed from the M395 equivalent to Deore XTs. They were on special then @ $320 for 2 Deore kits. I dumped the 1st brakes because they gave me problems, that no amount of servicing solved. Mostly with pistons staying open after only a few days exposed to dust.
The 1st brakes were very ordinary under load, especially under gravity on dirt. I only realized this this after I changed to the Deores. I like to feather the brakes and the Deores are truer and they are far more responsive. One thing about the Deore brake levers is that they are 2 finger levers not 3 fingers wide. I'm guessing longer levers are available, if you find using two fingers tiring. It gets cold touring in winter on the Divide and the Deore XTs coped well.
Not knowing what you will haul overall, I'm not sure that my figures are helpful, but here they are anyway. I haul an Extra Wheel Voyager Solo Trailer. The two heaviest weights carried so far have predominantly been on dirt, on the Bicentennial National Trail.
Including me, the bike and trailer, camera gear, supplies for an 8 weeks touring unsupported, bike maintenance gear, camping and snow gear and starting with 5lts of water each day, it has been 162 kg. Getting fractionally lighter each day by eating dehydrated food. The trailer has a limit of 30kg.
The rotors on my Anthem are 160mm. I haven't changed them. I carry spare brake pads and I haven't changed them either, in quite some time. I can't fit larger diameter rotors on the 26" Anthem without putting in a spacer between the fork and brake. I can only imagine that would be one more hassle to align and realign.
Lots of weight.
If you keep the Deore XTs maintenance timely ... I'm sure that you'll be happy with their performance.
Thanks for that Warren. Great pics you've got there too. You've covered a lot of ground.
Thanks for the Responses. Ive bought the Deore XT BR-M8000 and I'm buying some Shimano XT/Saint RT86 Ice-Tech 6-Bolt Disc Rotors to go with them, if they're still on sale when I hear back from Yuba.
All the Yuba authorities I've spoken to say that braking with a Yuba is unlike braking with a normal length bikes, so you have to brake harder on the back. I'm planning to do what some people do and buy a smaller disk in from and bigger in back. Some go with 160mm/180mm but I'm thinking to go with 180mm for the front and a 203 for the back.
Hi Rik, I totally forgot that my brakes are completely hidden behind the wheel guards on my Yuba to stop the kids putting their feet in a wheel! From memory, the rear brake needs an adapter for a rotor one size smaller than you are actually installing. So a 180 rotor needs an adapter intended for a 160. Pretty sure you can confirm this on the Yuba website. There should be plenty of room for the 200 rotor.
Well I'm glad to know your children's feet are protected. I read that a few children had that problem before Yuba recalled their bikes and put skirts on them all. Thanks anyway.
I've just made enquiries to Yuba and to Rohloff about compatibility. If Yuba say it's ok, then I'll do it. Meanwhile, after many hours research into Rohloff, I might end up ditching them. I was planning to pair a couple of XT-Saint RT86 Ice-Tech 6-Bolt Disc Rotors with my new Deore XT BR-M8000 brake set but only just read that Rohloff Speedhubs can only be paired with Rohloff discs. The Speedhub reviews are almost universally full of high praise but I haven't seen a word anywhere about these pretty ordinary looking hubs. Either way, I'll have that bike on Thursday, I'll have the new brake set a few days later, then the motor, so it's going to be like weeks of Christmas, and then I'll enjoy the building of the coolbox on the back for my organic produce too. SO yes I will Enjoy!
Thanks again, Rik