Different drop lengths on front and rear brakes. Is that normal?
06-13-13, 02:48 AM
#1
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Different drop lengths on front and rear brakes. Is that normal?
I have just fitted a new pair of 700C whels to the old British frame i'm using for a single speed buildup, and if i measure from center of the brake fixing hole to the center of the braking surface on the rim, the dimensions are - Front 70mm, Rear 50mm.
Is it normal to have different dimensions for front and rear. I dont have brakes yet and it looks as though they are sold in pairs of the same drop.
Is it normal to have different dimensions for front and rear. I dont have brakes yet and it looks as though they are sold in pairs of the same drop.
06-13-13, 05:49 AM
#3
Your cog is slipping.
Think about this for one second - depending on where the axle is in your rear dropouts, the measurement between the brake mounting hole and your rim's brake surface will fluctuate.
06-13-13, 07:46 AM
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Except that this is only true if the frame has rear facing track ends (dropouts). The OP says he is converting an old frame, which probably means it is a road frame with forward facing semi-horizontal dropouts that are parallel to the brake mounting hole in the seatstay bridge.
06-13-13, 07:51 AM
#6
Your cog is slipping.
Get off my spoon, TT. I'm blowing minds here.
06-13-13, 07:51 AM
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I have just fitted a new pair of 700C whels to the old British frame i'm using for a single speed buildup, and if i measure from center of the brake fixing hole to the center of the braking surface on the rim, the dimensions are - Front 70mm, Rear 50mm.
Is it normal to have different dimensions for front and rear. I dont have brakes yet and it looks as though they are sold in pairs of the same drop.
Is it normal to have different dimensions for front and rear. I dont have brakes yet and it looks as though they are sold in pairs of the same drop.
06-13-13, 07:53 AM
#8
Your cog is slipping.
He also said in another thread that his frame has 120mm rear spacing, which made me assume it was an old track frame.
06-13-13, 08:01 AM
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Old road frames also have 120mm dropout spacing. That's why they're so suitable for SSFG conversions.
06-13-13, 08:54 AM
#10
Your cog is slipping.
Last edited by Scrodzilla; 06-13-13 at 09:02 AM.
06-13-13, 11:08 AM
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Its an old road frame with dropouts not quite horizontal, but nice and long so ok to adjust chain using single speed.
The rear dropout is roughly tangential to the brake bolt hole so moving the rear wheel position will not change the distance of brake hole to rim.
I think you only get 10mm adjust on a brake so wil have to go for different drops on front and rear.
The rear dropout is roughly tangential to the brake bolt hole so moving the rear wheel position will not change the distance of brake hole to rim.
I think you only get 10mm adjust on a brake so wil have to go for different drops on front and rear.
06-13-13, 11:41 AM
#12
Fresh Garbage
Tektro r559 is the go-to long reach brake(53mm-73mm) since you can buy them with an external nut or recessed nut.
I see Harris Cyclery sells them individually, if you don't want a long reach for the rear
https://sheldonbrown.com/harris/brake...ers.html#55-73
I see Harris Cyclery sells them individually, if you don't want a long reach for the rear
https://sheldonbrown.com/harris/brake...ers.html#55-73
