Sub 28 Dj/Street (Scale Shots) W/Discussion (Scales Can Be Purchased @ At LPS)

PB Forum :: Dirt Jumping & Street
Sub 28 Dj/Street (Scale Shots) W/Discussion (Scales Can Be Purchased @ At LPS)
Author Message
flag crs-one
Posted: Feb 6, 2013 at 10:12 Quote
So Avid recently introduced a lighter BB7 caliper, meant for cyclocross racing (lighter by 25g, mostly by using titanium hardware). And it got me wondering, how light can you get a decent mechanical brake set-up? I did some quick math and it seems as though the typical BB7 set-up (Avid rotor, Speed dial lever) works out to around 480g...which is pretty heavy.
flag guancho-libre
Posted: Feb 6, 2013 at 10:14 Quote
I have a few dents but I doubt anyone is going to want to grind/slide and want that frame. Seems over the top to me.
flag harry-h
Posted: Feb 6, 2013 at 10:14 Quote
Easily shed some grammies on the lever. you only need 1 finger braking, so chop the end off. speed holes, split clamp. The usual.
flag raytheotter
Posted: Feb 6, 2013 at 10:48 Quote
Unsecure image, only https images allowed: http://cdn3.coresites.mpora.com/dirt_new/wp-content/uploads/2013/02/dj-head-tube-620x413.jpg
Unsecure image, only https images allowed: http://cdn3.coresites.mpora.com/dirt_new/wp-content/uploads/2013/02/dj-seat-clamp-620x413.jpg
The grind guards may be questionable but the rest of the frame has some really nice accents. And it's only 4.6lbs so it has a home here.
flag harry-h
Posted: Feb 6, 2013 at 10:54 Quote
that headtube badge is dope shit.
flag crs-one
Posted: Feb 6, 2013 at 11:32 Quote
harry-h wrote:
Easily shed some grammies on the lever. you only need 1 finger braking, so chop the end off. speed holes, split clamp. The usual.

Yeah that is true. To be honest I'm pretty content with the selection of levers available. Cable and calipers are the big porkers I think. It really surprises me that in all the years the BB7 has been available, and especially now that disc brakes are catching on in CX, that the best Avid can do is trim 25g by using titanium bolts.
flag hendu
Posted: Feb 6, 2013 at 11:38 Quote
crs-one wrote:
harry-h wrote:
Easily shed some grammies on the lever. you only need 1 finger braking, so chop the end off. speed holes, split clamp. The usual.

Yeah that is true. To be honest I'm pretty content with the selection of levers available. Cable and calipers are the big porkers I think. It really surprises me that in all the years the BB7 has been available, and especially now that disc brakes are catching on in CX, that the best Avid can do is trim 25g by using titanium bolts.
Never really put much thought into before but that makes a lot of sense.
flag raytheotter
Posted: Feb 6, 2013 at 11:41 Quote
crs-one wrote:
harry-h wrote:
Easily shed some grammies on the lever. you only need 1 finger braking, so chop the end off. speed holes, split clamp. The usual.

Yeah that is true. To be honest I'm pretty content with the selection of levers available. Cable and calipers are the big porkers I think. It really surprises me that in all the years the BB7 has been available, and especially now that disc brakes are catching on in CX, that the best Avid can do is trim 25g by using titanium bolts.

You could save a load of weight if you used Powercordz. 2.9g per metre.

Stupidly expensive though.

Edit:

http://www.powercordz.com/brake-cables/prime-mtn-brake
flag kanioni
Posted: Feb 6, 2013 at 12:25 Quote
That's an option only if it doesn't pull your brake when spinning bars. Otherwise it's back to steel cable with linear outer cable.
flag nwthumbs
Posted: Feb 6, 2013 at 12:55 Quote
crs-one wrote:
So Avid recently introduced a lighter BB7 caliper, meant for cyclocross racing (lighter by 25g, mostly by using titanium hardware). And it got me wondering, how light can you get a decent mechanical brake set-up? I did some quick math and it seems as though the typical BB7 set-up (Avid rotor, Speed dial lever) works out to around 480g...which is pretty heavy.
well the CX ones are 1:1. So x lever how much lighter with a stubby mono lever?
flag crs-one
Posted: Feb 6, 2013 at 13:09 Quote
I'm going to disappear into the internet and Excel to do some research. I'll report back when I've got an idea of what's what.
flag willy94
Posted: Feb 6, 2013 at 13:24 Quote
crs-one wrote:
I'm going to disappear into the internet and Excel to do some research. I'll report back when I've got an idea of what's what.

just weighed what i have.

med. oddy monolever (full hardware): 100g

full length k-sheild w/ends (48"): 58g

teflon inner cable (full length): 23g
flag crs-one
Posted: Feb 6, 2013 at 13:46 Quote
Alright, after delving into MTBR here's three possible BB7 setups:

The "stock" build, what you'd get if you went out and bought one today.
BB7 155
FR-5 78
Cable 102 (60" of 1.5mm inner + 5mm outer)
Pads 24
160mm HS1 93 (though obviously it comes with the shittier one, the G2 or whatever)
Rotor bolts 14
CPS bolts 21
Adapter 20
Adapter bolts 11
518

Next there's what I would call the street bike build. If you can get ahold of a 2007 or earlier caliper, the grey one, which is lighter, that's a good thing.
2007 BB7 142
Fly Lever 65
Cable 102
Pads 24
140mm Hope rotor 74
rotor bolts 13
CPS bolts 21
Adapter 14
Adapter bolts 11
466
Note that not only is the rotor quite a bit lighter, but the adapter you would use is also lighter.

Finally there's the full weenie build. I'm sure you could save some weight on the cable but I couldn't find a good resource for that.
BB7 SL w/ pads 159
Tektro RL720 45
Cable w/ inline barrel adjuster 106 (recommended since there's no barrel adjuster on the caliper)
140mm Alligator rotor 62
titanium rotor bolts 7
CPS bolts 16
Modded adapter 12
titanium adapter bolts 7
414

Interestingly the Tektro lever, which is a CX lever, is actually pretty damn cheap. All the same, this compares to my current brake, which is a current-generation XT with a 140mm Hope rotor, at 425. There's also a pretty long thread about modding the caliper with a dremel to save weight, but it's pretty slim, so I chose not to include it.
flag Jose-David-DH
Posted: Feb 6, 2013 at 13:47 Quote
Brooklynuk85 wrote:
Unsecure image, only https images allowed: http://cdn3.coresites.mpora.com/dirt_new/wp-content/uploads/2013/02/dj-head-tube-620x413.jpg
Unsecure image, only https images allowed: http://cdn3.coresites.mpora.com/dirt_new/wp-content/uploads/2013/02/dj-seat-clamp-620x413.jpg
The grind guards may be questionable but the rest of the frame has some really nice accents. And it's only 4.6lbs so it has a home here.
what frame is that? Drool

 


Copyright © 2000 - 2024. Pinkbike.com. All rights reserved.
dv65 0.065788
Mobile Version of Website