Author Topic: Rear Brake positions (Read 6614 times)

Peter J · « **on:** February 27, 2011, 01:36 PM »

Why are some rear brake lugs on the seat stays and others on the chain stay?

and whats the advantages of each design ?

JT71 · « **Reply #1 on:** February 27, 2011, 02:21 PM »

i have seat stay brakes, but i understand chain stay brakes are the most efficient ones for braking power.

not sure seat stay have an advantages other than they never interfere with the chain, some brakes on chainstay brakes can be a problem with todays smaller sprocket. (chain ring if you're old skool. lol)

sure someone more knowledgable will be along to put me right shortly.

dordymush · « **Reply #2 on:** February 27, 2011, 02:29 PM »

yeah they are a pain on the chain stays.
lowest i can run is a 33/13 and that was with me grinding the brake cone down a bit.
could do with seeing if theres any flatter type for mine.

dordymush · « **Reply #3 on:** February 27, 2011, 02:48 PM »

i'll have a look at them glen

Betty · « **Reply #4 on:** February 27, 2011, 04:42 PM »

I've had a Fly frame with chainstay mounts and a Fly brake ran 28/10 with no issues, there was enough clearance for 25/9

Current frame has seat stay mounts, i'll be honest there's no noticable differance in stopping power

Let the debate begin....

TwoBobRob · « **Reply #5 on:** February 27, 2011, 05:01 PM »

I can sense Alex lacing his boxing gloves up at this very moment......

JT71 · « **Reply #6 on:** February 28, 2011, 12:27 PM »

i guess it's not about stopping power, more gripping power, if you're doing techy mini ramp stuff, on the back wheel, brake held on, then a rider might feel flex in the stays, and more so on the seat stays than on the chain stays.

yeah Rob....where is Alex? lol.

SaMAlex · « **Reply #7 on:** February 28, 2011, 12:45 PM »

Bah, I cant be arsed!

Chainstay = Better cable routing (esp if you use a gyro), better outercable stop (if you use the seat tube), cleaner/better looking. Stronger setup cos the brake is pulling TOWARD the frame, not away from it.

Seat stay = Better if you run a tiny gearing. There is NO other reason to put the brake up there. (btw, my 28:10 fits with a chainstay brake just fine)

JT71 · « **Reply #8 on:** February 28, 2011, 01:18 PM »

i knew he couldn't resist!

generallee · « **Reply #9 on:** March 01, 2011, 07:23 PM »

Righty Ho.
Brakes used to be ont eh Chainstay all the time, as 44:16 gearing never interfered with the brake. Some flatlanders had seatstay mounts for their smaller gearing, when frames werent designed around small front chainrings.
Then , as newer smaller gearing came in, seatstay mounts became more of a regular thing to get the lower, smaller chain/sprockets out of the way of the rear brake.
But now, frames that have chainstay mounts can take 25/9 gearing no problem. It's all about frame companies designing the chainstays/BB junction to accommodate little gearing. Deluxe, Terrible One, Fly etc - all have done or do this.
I recently had my custom S&M made - with chainstay lugs. It make perfect sense - the brake is being pulled ONTO the frame with the momentum of the wheel - rather than ppulled AWAY from the seatstays when you have brake mounts up top. Hence the reason you barely see a cracked chainstya brake lug. But you do see them on seatstays...
I wish Id had my 2nd trails frame from S&M done with chainstay lugs too - I forgot to put it in the order - bah.

pickle · « **Reply #10 on:** March 01, 2011, 07:32 PM »

ive never owned a frame with chainstay lugs.......that was until you posted up that bloody Winstanleys link you sod!!

dordymush · « **Reply #11 on:** March 01, 2011, 07:33 PM »

i think my probs is with the shitty brake i got at the minute.
gonna have a look at that evo brake.

right then while were at it.
whats the best brake pads for coloured rims.

pickle · « **Reply #12 on:** March 01, 2011, 07:37 PM »

Dave, for the money you can't get any better than the Diatech AD999. Have a look on BMX Citys ebay store......i run them on both mine and they're lovely and light and low stack height all for £24 posted! they were £60 when the came out

here you go Dave, they have slightly angled arms for better cable line

http://cgi.ebay.co.uk/BMX-U-BRAKE-Diatech-AD999-Box-U-Brake-/400151054282?pt=UK_sportsleisure_cycling_bikeparts_SR&hash=item5d2adc87ca

hunterdubber · « **Reply #13 on:** March 01, 2011, 07:38 PM »

Are you not riding brakeless yet Dave

and wearing your pants round your ass

Get wiv it

dordymush · « **Reply #14 on:** March 01, 2011, 07:46 PM »

i tried the girly jeans but could'nt get my foot through the hole

.

i'll have a look at them rob.
not worth me spending loads for what bit of riding i do.

TwoBobRob · « **Reply #15 on:** March 01, 2011, 08:06 PM »

I've got one of those AD999s, can't fault it really, it's just like a posh Hombre.

Stodgy has some good brake blocks to suit anno'd rims in stock, I just can't remember the name of em......

SaMAlex · « **Reply #16 on:** March 01, 2011, 08:08 PM »

Quote from: pickle on March 01, 2011, 07:37 PM

they have slightly angled arms for better cable line

?

Must .... not .... get .... involved ....... must ..... keep .... mouth ..... shut .......

TwoBobRob · « **Reply #17 on:** March 01, 2011, 08:09 PM »

pickle · « **Reply #18 on:** March 01, 2011, 08:19 PM »

Quote from: S&MAlex on March 01, 2011, 08:08 PM

Quote from: pickle on March 01, 2011, 07:37 PM
they have slightly angled arms for better cable line

?

Must .... not .... get .... involved ....... must ..... keep .... mouth ..... shut .......

not my view Alex just quoting the sales pitch

dordymush · « **Reply #19 on:** March 01, 2011, 08:32 PM »

Quote

Must .... not .... get .... involved ....... must ..... keep .... mouth ..... shut ......

instead of keep ya mouth shut why dont you just give me your opinion so i dont waste my money on something i dont know about but seems you do.

SaMAlex · « **Reply #20 on:** March 01, 2011, 09:29 PM »

Quote from: dordymush on March 01, 2011, 08:32 PM

Quote
Must .... not .... get .... involved ....... must ..... keep .... mouth ..... shut ......
instead of keep ya mouth shut why dont you just give me your opinion so i dont waste my money on something i dont know about but seems you do.

Sorry, this is why the joke was made at the start of this thread. I spend WAY to much time getting worked up about bad brake positions and poor ways of pretending to overcome one of the problems.

When you have the brake on the seat stay and the outer cable stops on the toptube, the hanger wire isnt in line with the movement of the brake arms. You are pulling against the pivot, not with it. You get the same problem if you have a chain stay brake and the cable stop on the down tube. The better way is to have the cable stop on the seat tube, so the inner wire/hanger is parallel with the tube that the brake is mounted on. This is harder to do with a seat stay brake cos the seat post is in the way.

Fly had the idea of putting a bend on the arms. This makes takes the bad alignment, and spreads it over 3 points, rather than just 2. It makes the problem look slightly better but it solves nothing. It also drops the cables further away from the frame which give it a droopy, saggy look.

Bent brake arms dont solve the alignment issue with seat stay brake, but I guess they dont make it any worse.

Deep breath ..... Deep breaths ......

dordymush · « **Reply #21 on:** March 01, 2011, 10:11 PM »

ah i see what your saying.
its a wonder somebodys not done something by now................................or am i starting you off again

SaMAlex · « **Reply #22 on:** March 01, 2011, 11:02 PM »

They have done something ...... they all stopped using brakes!!

Or they got a custom made frame with chain stay brake mounts

TwoBobRob · « **Reply #23 on:** March 02, 2011, 01:04 AM »

Although.......

What we're talking about here are engineering observations and solutions; degrees of perfection. Breaking a lug off aside, we can live long and happy lives (apart from Captain Chainstay over there...) with our brakes mounted upstairs or downstairs, just so long as they're set up properly. Truth is, brakes can be so good with a little tweaking that they become too good, if you catch my drift. No feel or progression unless you have a bloody good trigger finger.

New cable nicely lubed, avoid a gyro unless you really want one, very clean lugs so the arms are as free as a bird on them and lubed with grease or copperslip. Whatever pads Stodgy tells you will work with your rims, and not too much tension on the springs - don't be tempted to crank them round, usually a 1/4 of a turn or less will do once you've taken up the slack. The stiffer the spring tension, the harder the lever. Just dial in enough so the brakes snaps nicely back off the rim.

Jobs a good 'un

JT71 · « **Reply #24 on:** March 02, 2011, 08:09 AM »

Quote from: TwoBobRob on March 02, 2011, 01:04 AM

- don't be tempted to crank them round, usually a 1/4 of a turn or less will do once you've taken up the slack. The stiffer the spring tension, the harder the lever. Just dial in enough so the brakes snaps nicely back off the rim.

Jobs a good 'un

this is one of the first things i learnt about new school brakes, from Rob, and i still turned up at Creation with a lousy back brake. I had barely 1/4 turn on and it was too much. (this came from hastily finishing putting my bike back together in time to ride) Now I have just enough tension to move the blocks away from the rim and that's it, it nearly, very nearly feels as good as Alex's.....but it'll never be that good on account of mine being on the seat stays eh? lol.

Alex makes a good point about the cable routing, where my inner exits the outer at the top tube cable stop it is instanly forced at an angle towards the brake arms so the inner is always rubbing on the outer at an angle. I have seen angled cable stops on some frames but I don't have the balls to try to bend mine to suit......but if i never move my seat post i could drill through the seat tube, and post and put a stop in there right? mmmm maybe i won't. lol.

Author Topic: Rear Brake positions (Read 6614 times)

JT71

JT71

SaMAlex

JT71

SaMAlex

SaMAlex

SaMAlex

JT71