AVID disc - Road vs MTB?

[Zebee Johnstone]

I see on Dean Woods Direct that the Avid BB7 disk brake comes in a
road and MTB version.

What's the difference?

Zebee

[Joel Mayes]

On 2007-06-17, Zebee Johnstone > wrote:
> I see on Dean Woods Direct that the Avid BB7 disk brake comes in a
> road and MTB version.
>
> What's the difference?

Different mechanical advantages.

The BB7 road will work with drop-bar levers (or old canti levers) while
the MTB version requires the greater mechanical advantage of direct-pull
brake levers.

Cheers

Joel

--
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| Affordable second hand bikes
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[DaveH]

lever pull?

Dave H

"Zebee Johnstone" > wrote in message
...
>I see on Dean Woods Direct that the Avid BB7 disk brake comes in a
> road and MTB version.
>
> What's the difference?
>
> Zebee
>

[Zebee Johnstone]

In aus.bicycle on 17 Jun 2007 09:31:50 GMT
Joel Mayes > wrote:
> On 2007-06-17, Zebee Johnstone > wrote:
>> I see on Dean Woods Direct that the Avid BB7 disk brake comes in a
>> road and MTB version.
>>
>> What's the difference?
>
> Different mechanical advantages.
>
> The BB7 road will work with drop-bar levers (or old canti levers) while
> the MTB version requires the greater mechanical advantage of direct-pull
> brake levers.

I suspected it might be a lever thing. as the 'bent has Avid
cantilevers that can't really be called "old" I guess I need the MTB
version.

And no doubt some new cable. I presume I just need new inners, and
the outers stay the same? Just a lot of cable running down closer to
the hub?

Zebee

[Dave]

On Sun, 17 Jun 2007 10:03:50 +0000, Zebee Johnstone wrote:

> And no doubt some new cable. I presume I just need new inners, and
> the outers stay the same? Just a lot of cable running down closer to
> the hub?

You're better off doing the outers at the same time. It's about $10/m from
memory and you'll need less than that, and that way you've got the right
length. Unlike hydro systems (like your silly motorised bikes), cable
brakes have friction and suffer when the cable goes through bends. Keeping
the cable at the right length has noticeable effects on the braking.

If you're playing upgrades then I'd highly recommend replacing the outer
and inner, and if you want to borrow a set of cable cutters, sing out. Oh,
and I've forgotten to post that reflective tape, so I'll have a look for
that tomorrow.



--
Dave Hughes |
Frankly, your argument wouldn't float were the sea composed of mercury.
- Biff

[Joel Mayes]

On 2007-06-17, Zebee Johnstone > wrote:
> In aus.bicycle on 17 Jun 2007 09:31:50 GMT
> Joel Mayes > wrote:
>> On 2007-06-17, Zebee Johnstone > wrote:
>>> I see on Dean Woods Direct that the Avid BB7 disk brake comes in a
>>> road and MTB version.
>>>
>>> What's the difference?
>>
>> Different mechanical advantages.
>>
>> The BB7 road will work with drop-bar levers (or old canti levers) while
>> the MTB version requires the greater mechanical advantage of direct-pull
>> brake levers.
>
> I suspected it might be a lever thing. as the 'bent has Avid
> cantilevers that can't really be called "old" I guess I need the MTB
> version.

I tink I meant to type old-style i.e. traditional cantis with a straddle
cable or yoke, not direct-pull cantis (V-Brakes). I'd say you probably
need the road version, but without seeing your levers...

> And no doubt some new cable. I presume I just need new inners, and
> the outers stay the same? Just a lot of cable running down closer to
> the hub?
>
> Zebee

It worth replacing the outer if it hasn't been done in a while, or if
the inner is dirty or rusty in any way. Also if the outer came with the
bike it's a good bet some sections are not the ideal length look at the
ends of the outer and see if it is damaged where the cable leaves the
stop/brake/mech/whatever. if there's a sharp kink there the cable is
slightly to short.

Cheers

Joel


--
Human Powered Cycles | High quality servicing and repairs
| Affordable second hand bikes
(03) 9029 6504 | Bicycle reuse centre
www.humanpowered.com.au | Mechanical and on-road training and instruction