We have a tester that will be trying this on his Schlumpf.
I’m hoping that without crankstops, the chain ring spacers will be enough to align the rotor if the cranks creep toward the frame. I also wonder if a crank stop on the right side will be an issue on a Schlumpf despite knowing it would interfere on the left side.
The foremost authority on the subject suggested he didn’t see a problem using the brakes with the hub, but you can’t foresee everything and I don’t intend to hold him to it… There was no endorsement; This is an experiment -we’ll see. There was no mention of crank stops.
Our testers are one enthusiast, and two professional testers that we discovered through the forum. The tester that has the Schlumpf has a high degree of knowledge regarding such hubs and likely the forces involved. The benefits of disk brakes are desirable at the speeds of geared systems, if those systems tolerate the brakes… Yipee!
We’re ironing out the details of eCommerse, getting distributorship and parts, and then sending the parts to our testers. There may be a further delay, as the desire for bolt on systems greatly exceeds that of weld on systems and problems like annealing hardened aluminum frames by welding, which has our focus on engineering a universal bolt on caliper mount. (It’s in the works.) This is the sort of thing we need to test, and a complete bolt on system is what people seem to want to buy.
im just wondering with the disc mounted to the Schlumpf axle wouldnt there be a little bit of backlash when using the brakes?
if you stop the axle the hub would still have play within the gears and would cause a slight slipping feel,with a HS33 you wouldnt feel this as bad,because the rim is slowed down.
We have not begun testing, but these questions are excellent! I hope to have feedback regarding geared hubs in about a month. We have the right guys on the case and I’m excited to have the right questions to ask! Thanx, keep asking these types of questions!
I reposted some questions in the Schlumpf general discussion Schlumpf hubs: general discussion. post #95 got some answers from Jogi that seemed very reasonable which I copied and pasted in this post:
One suggestion on geared hubs. If you brake through(attached to crank) the gearing, it puts a lot of stress on the gears,you would be using the gears to take up all the braking weight. If you brake at the hub it stops the wheel no gearing involved, and at the price of a geared hub, more undue stress through the gearing could have expensive/catastrophic results.
-Lobbybopster
In my opinion it won´t stress the hub more than you can do by your leg power. the hubs are designed to withstand drops up to 5 feet, and even droping 2 or three feet with landing power on back leg will put more energie into the hub than any brake can do. http://blog.ridetriton.com/__oneclic...schlumpf-3.jpg
Quote:
Originally Posted by kb1jki View Post
im just wondering with the disc mounted to the Schlumpf axle wouldn’t there be a little bit of backlash when using the brakes?
if you stop the axle the hub would still have play within the gears and would cause a slight slipping feel,with a HS33 you wouldn’t feel this as bad,because the rim is slowed down.
any input to this?
I am not quite sure but for example, rolling down stairs with or without using magura brake I feel not the play within the gears
Quote:
-filotr14lsdude
If you use a drag brake, what additional strain does it place on the gears that your legs don’t when slowing down?
-KB1JKI
I guess smooth downhill braking is much better for the hub than changing leg brake power at each revolution.
We have found a resource for chain ring spacers that can be moved from the inside of the crank to the outside as the crank may creep inward to adjust the rotor outward about 3mm, if you order extras -even further. This should take care of our square taper customers. I don’t see any need for adjustment for Isis customers with crank stops. I wonder how much the Schlumpf may creep overall though.
I just handed the machinist a chunk of aluminum to one off our bolt on caliper mount prototype. It may be something I can patent, because of it’s uniqueness and universal nature… We’ll see.
More than square-taper I would guess, because the taper on ISIS is much shallower (it wasn’t meant to stop the crank, just take up any slop in the splines). People have been talking on the Schlumpf thread about actually having to machine the inside of the cranks out because they creep so far onto the axle.
Perhaps steel cranks would work better on a Schlumpf.
if the rotor could compensate for 5mm of allowed creep be fair to offer? I mean, without crank stops, how much forgiveness can be afforded? I think that’s as far as I can go with chain ring spacers. if I shim the caliper as well, I could probably get another 3mm… that’s nearly 1cm… that’s a pretty good tolerance right?
EDIT: I think the OP’s comment that it’ll be cheaper than [a Magura HS33]
is interesting though. New, maybe, but HS33s are so common they can be picked up on ebay very cheaply (the two I’ve got on my unicycles cost be £4 and £10 respectively after reselling the other half of the brake, Evo mounts and boosters).
[/quote]
You’re right, we’ll compare with the new HS33, but maybe when you can pick up MountainUni.com Disk Brakes used, they’ll cost something similar. Also, the system consists of a crank, mount, rotor, and brake… if you get a shimano deore brake or avid mechanical caliper, they only cost $50, the crank $60, and we’re working on a cost of rotor looking better with laser cutting in bulk… will update soon. We may upcharge the crank an additional amount if we offer a dual hole solution. We’re discussing it with the manufacturer, but it’s a steep investment for the initial run… We’ll see! that would be like two upgrades in one, a dual hole disk brake upgrade.
you can compare prices if it has the same brake - character.
if testing shows benefits, or different brake - charakter than its not only a question of price;)
I love to have different options in unicycling gear and i think there can´t be to much developement in such things…
this is what they look like from the machinist, from the manufacturer, the holes would be powder coated too. I just wonder if we should sell all the sizes of Sinz, or all dual hole, and if all dual holes we offer just be 150/125.
It’s great to see your innovation getting ready to make it to the market. You all did a great job, with excellent attention to detail. I really like the way your company name is cut into the rotor as well. Excellent work!
Thanks Rhino, glad you like them. Like KB1JKI says, A bolt on Mount is in the works, for all applications. We believe this is an innovation that all 26-29-36 wheels will benefit from. And we think the dual hole is the ideal compliment for a disc brake, since stopping power is lost and speeds potentially increased with the shorter insert.
Send me a PM, I can tell you more about this pair’s soon to be destination.
These are too cool! I like to see designs that make use of what’s there, ie, chain ring mounts for bicycles for a disc brake. Fewer new parts I think is a win all around.
I’m probably not the person to ask advice from, but since you put it out there, here are my thoughts on crank lengths. I would not buy the dual-holed 125/150s. I’d buy the 115s and wish I had 110s. And then since I had a brake I’d probably be brave enough to put my own holes in somewhere around 90mm. I ride (rode, hopefully will ride again) a 36 with 110s brake-less at the moment. On the other hand, if you had some 100/115mm cranks you could count on at least one sale.
I’m not a huge fan of branded gear. More personal preference than anything, and I’m sure many feel the opposite way, but being forced to advertise someone’s brand in order to use (after paying for) their equipment makes me stop and really re-assess the gear’s worth. I’d jump at a non-branded rotor with less hesitation.
If you’re being serious, I’d prefer a simple non-branded rotor, just some holes, something like what is on almost every bicycle disc brake I see.
If you’re snapping back at what was an (apparently either failed or unwanted) attempt to give some feedback and express my thoughts as a very likely customer, well, I’m sorry.
Either way, I understand that there’s a lot more to this from your perspective. Branding gear must be something most brands do for a reason. Realistically, I will probably buy your brake, branded or not. I would just like it better without your website url on it. I represent only myself in this sentiment.
I doubt the custom thing would be affordable, but we could feature other brands branding if they commissioned it. Most brands brand their product, and since we can’t use stickers that you can peel away, then we vent our rotors with our brand. Branding works to sell more stuff, because the success of a brand is knowing what to expect and living up to it. We may also brand lifestyle themes into the rotor, not custom… and suggestions are what forums are about. Gassing may not even be an issue for these brake rotors at unicycle speeds so we may not even have to cut holes in the rotors… but it looks the part and we have only just begun considering options for the etching. Sure I care what you think, but never enough to get snappy though. Opinions help. Thanx for yours.
