Shi**no roller brakes - scratching my head

[mickle]

I've a pair of Shi**no 'M' brakes, or roller brakes on my new bike. The rear works acceptably well (not quite as good as a well set up V brake, more like old skool cantilever power I suppose). It won't lock up but that's probably got a lot to do with the enormous weight of the bike and me sitting upright and right over the back wheel. The front brake is shockingly bad, it'll scarcely stop the bike at full pull.

I happened to have a spare roller brake assembly knocking around the garage so fitted that, to no effect. It's still shoot.
I've read some reports of roller brakes being enormously powerful, perfectly suited to cargo bike use. So what's going wrong with mine? I've had them off and nosed around inside, put grease where it indicated. To no avail.

Does anyone have any knowledge of roller brakes? Give me any rim brake on the planet and I'll get it to work - but I haven't got a clue about these things. They can't possibly be as crap as they are, and why are two totally unconnected units as crap as each other? Do they want new bits? Do they need replacing? Do they need cleaning? Regreasing? WTF.

Help me out here before I crash in to something.

 

[Andy_R]

sheldon of the beard recommends this: rollerbrakes. I've seen some discuussion re removing the power modulator on the front brake, but the general consensus is that they're no use for front ends.

edit: just checked shim**o tech docs, they don't recommend use with a gross weight of more than 100kg.

 

[tyred]

edit: just checked shim**o tech docs, they don't recommend use with a gross weight of more than 100kg.

They're not very useful then. I weigh about 90kg myself, + weight of my steel bikes (some of which are old and very heavy) and a few odds and ends of luggage and I am well in excess of 100kg gross.

 

[mickle]

Interesting, thanks.

Bugger.

 

[mickle]

I wonder if these have the infamous power modulator, and if it can be removed..There does seem to be a power level after which any more pulling at the lever generates nothing but squidge. I thought it was general crapness or worn-outness but I'm happy to believe that Shi**no sabotaged them in the factory.

 

[Jelly Mould]

I had roller brakes on one of my bikes. The front was pretty useless - I ended up taking apart the front hub to investigate the "Power Modulator" further. It's a multi-plate grease-lubricated clutch - I stripped the grease away, and tightened the whole thing up.


This helped a little, but was still not that great - I then replaced the roller brake unit from a BR-IM45 to a BR-IM70 (much bigger cooling fins). This worked brilliantly at first, very similar to disc brakes, but once it bedded in it became less powerful - but still much better than the previous unit. I always found that the brake worked best when running out of grease - I guess when it was brand new, the grease had not distributed itself all over the rollers...

 

[mickle]

Thanks Jelly Mould. Maybe I just need a new brake assy.

 

[Andy_R]

even the IM70 isn't recommended for use in excess of 100kg.......get v's on front instead!

 

[mickle]

I've got a strap-on v plate already, though it won't be a very tidy fit on the front.

Looks like that's the solution...

 

[GrumpyGregry]

even the IM70 isn't recommended for use in excess of 100kg.......get v's on front instead!

That is what Chris Juden of the ctc told me to do when I wanted to go tour on my hub braked/geared atb in 2000.

I ignored his advice. It cost me.

 

[Davidc]

One of the bikes I hired in NL a few years back had hub brakes made by S'mano - I nearly ended up under a tram 5 minutes from the bike shop and took it back. I gathered from the woman in the shop that the bike was new and they hadn't got round to changing it, which they always do because the hub brakes are no use. (That bike must have weighed 100kg on its own).

 

[Zoiders]

Cycle jumble and find a Sturmey roller with the Steelite shell.

 

[mickle]

Cycle jumble and find a Sturmey roller with the Steelite shell.

Sturmey don't make a 'roller' shirley?

 

[tyred]

I have an Elswick with Sturmey drum brakes and I'm not overly impressed with them.

 

[Zoiders]

Sturmey don't make a 'roller' shirley?

They have before now, it wasn't internal to the hub body like a drum and it lived in a steelite plastic shell one side of the hub.