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Old 08-13-12, 06:42 PM   #1
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Weinmann 610/750 Front/Back... Why Was This Done?

Just an observation on most of the Weinmann brakes I've accumulated - it seems often that they had a 610 up front and a longer reach 750 in the back. On a 27" wheel on my bikes the 610 will have the pad at the max extension position, and the back will be about mid-

So, this brings questions to mind:
Why was this done if a 610 would have reached on both ends?
Would the 750 be adequate to accommodate 700C rims?
Is the any reason the rear 750 couldn't be used as a front brake?
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Old 08-13-12, 07:10 PM   #2
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Used to be kinda the standard. No real reason except when the rear one is too short. Really depends where they decided to braze the brake bridge.

Yes, you can swith short and long to front or back to fit your needs by changing the center bolt. Front and rear are different lengths.
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Old 08-13-12, 07:53 PM   #3
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I think that there is a real reason, and it has to do with long chainstays on older bikes (which, apart from ride characteristics, helped allow getting the wheel in and out of a frame having both horizontal dropouts and fenders). Once the fender is set to have clearance in front of the wheel, it looks funny if the clearance at brake bridge is much closer, so additional clearance was provided there too. Result: you need a longer reach brake in the rear (how much? Oh, about 14 mm according to Weinmann). Without fenders, the "roughly equivalent clearance" problem isn't really a factor; so the brake bridge can be lowered, as it is on many bikes that followed the "please, no fenders, we're not British" fad.

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Old 08-14-12, 07:12 AM   #4
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Thanks for the replies. Has anyone tried using the 750's to mount a 700c into an originally 27" wheeled frame? Is the reach enough?
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Old 08-14-12, 08:35 AM   #5
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From Charles answer: the 750 have an extra 14mm reach and that should be enough to reach to 700c wheels since these are just 4mm lower (622mm diameter rims vs. 630mm). Depends on how high the brake bridge is on the frame.
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Old 08-14-12, 09:21 PM   #6
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I have an old English frame that originally took a Weinmann 750 on the rear (with 27" rims, presumably) -- I converted it to 700C, and the 750 works for that too. Pads are near the bottom of the slots, though. As leecycle says, the difference is only 4 mm in reach.
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Old 04-17-17, 08:00 AM   #7
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Thanks for the replies. Has anyone tried using the 750's to mount a 700c into an originally 27" wheeled frame? Is the reach enough?
Yes, sorry to necro an old post as I was looking at the comments about 750 and 610's. I have just such a setup on my old CCM frame which originally had 27" wheels but was swapped to 700c. Granted I switched things around and have the 610 in back and the 750 up front.

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Old 04-17-17, 08:56 AM   #8
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Yes, sorry to necro an old post as I was looking at the comments about 750 and 610's. I have just such a setup on my old CCM frame which originally had 27" wheels but was swapped to 700c. Granted I switched things around and have the 610 in back and the 750 up front.
The reason that many companies positioned rear brake bridges to require longer calipers was to reduce wheel lockup with inexperienced riders who typically applied equal pressure to both levers. Under normal braking the rear wheel becomes unweighted, increasing its tendency to skid. Longer brake arms flex more, reducing this tendency. Most modern brakes are designed with equal length arms, but the rear calipers are often designed with thinner arm sections, to make them flex more.

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Old 04-17-17, 04:49 PM   #9
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The reason that many companies positioned rear brake bridges to require longer calipers was to reduce wheel lockup with inexperienced riders who typically applied equal pressure to both levers. Under normal braking the rear wheel becomes unweighted, increasing its tendency to skid. Longer brake arms flex more, reducing this tendency. Most modern brakes are designed with equal length arms, but the rear calipers are often designed with thinner arm sections, to make them flex more.
T-Mar, I'm surprised... assuming the same section thickness, greater flex cannot be denied, but surely the greater effect is the reduced mechanical advantage with the longer caliper arms.
Of course an argument in favour of longer arms in the front with a ham-fisted rider, is reduced likelihood of an endo...
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Old 04-17-17, 06:38 PM   #10
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Would the 750 be adequate to accommodate 700C rims?
I've Weinmann 750s F&R on the gaspipe Raleigh with 700Cs, although the front could take 610s.
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Old 04-17-17, 07:05 PM   #11
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Originally Posted by Niteshooter View Post
Yes, sorry to necro an old post as I was looking at the comments about 750 and 610's. I have just such a setup on my old CCM frame which originally had 27" wheels but was swapped to 700c. Granted I switched things around and have the 610 in back and the 750 up front.

Sweet Targa build! As someone who grew up with CCM gaspipe, it's great to see one so nicely put together. Most weren't!.
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Old 04-17-17, 08:03 PM   #12
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T-Mar, I'm surprised... assuming the same section thickness, greater flex cannot be denied, but surely the greater effect is the reduced mechanical advantage with the longer caliper arms.
Of course an argument in favour of longer arms in the front with a ham-fisted rider, is reduced likelihood of an endo...
Concur. With a 750 rear / 610 front setup, as on my old Nishiki Competition and on both Capos, the rear brake will apply first, but with somewhat less force than the front. To prevent a rear wheel skid, we want more braking force in front than in back, and the 750/610 combo achieves this naturally, given roughly equal left-right hand grip force.

Even my Bianchi (Modolo sidepulls originally, now Campag. sidepulls) uses somewhat longer arms in back than in front.

Regarding 622mm (700C tire) vs. 630mm (27" tire) rims, I have always had tall enough brake arm slots to engage either size by moving the pads up or down 4mm.
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Old 04-17-17, 09:39 PM   #13
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The reason that many companies positioned rear brake bridges to require longer calipers was to reduce wheel lockup with inexperienced riders who typically applied equal pressure to both levers. Under normal braking the rear wheel becomes unweighted, increasing its tendency to skid. Longer brake arms flex more, reducing this tendency. Most modern brakes are designed with equal length arms, but the rear calipers are often designed with thinner arm sections, to make them flex more.
Thanks! Didn't know that.

What I found interesting was that I went from bicycles to motorcycles and noticed that the brakes were reversed, e.g. front brake on the bicycle was on the left and on the motorcycles I owned on the right. I actually switched my bicycles for several years to the same M/C configuration then back so that if a non M/C rider happened to ride one of my bikes they wouldn't get confused.
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Old 04-17-17, 09:55 PM   #14
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Sweet Targa build! As someone who grew up with CCM gaspipe, it's great to see one so nicely put together. Most weren't!.
Thanks! I always liked to be a bit different! And yes I spent a couple of summers in the basement of a K-Mart putting CCM Targas together. Nothing special about those ones, but got the frame and thought what the heck. Picked up most of the parts at a couple of store close outs cheap. The bike is surprisingly light given the frame, will have to borrow a luggage scale and get a true weight one day as I'm kind of curious. It doesn't feel any heavier then my 'better' road bike.

Some other pix posted at the bottom of the thread here, Two Iverson's and a CCM
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Old 04-17-17, 10:14 PM   #15
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What I found interesting was that I went from bicycles to motorcycles and noticed that the brakes were reversed, e.g. front brake on the bicycle was on the left and on the motorcycles I owned on the right. I actually switched my bicycles for several years to the same M/C configuration then back so that if a non M/C rider happened to ride one of my bikes they wouldn't get confused.
FWIW, quite a few cyclists prefer and use right hand for the front brake, myself being one of them. We used to call this set up Italian style, because it's the standard for Italian racers. Check out some Giro pictures...

I don't even ride M/C, but I've used right front on every bike I've had since I was 15, and I'm not going to change now. If someone else rides my bikes and gets confused, too bad.
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Old 04-18-17, 11:31 AM   #16
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[b]....greaterr flex cannot be denied, but surely the greater effect is the reduced mechanical advantage with the longer caliper arms...
Yes, increased flex and decreased mechanical advantage.
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Old 04-18-17, 04:48 PM   #17
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Yes, increased flex and decreased mechanical advantage.
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