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Currently I am debating with what to replace the handle bars and brakes on an old bike. One option are drop bars. However, a concern is that braking from the hoods was unsafe in old bikes. However, I might be able to fit a recent Shimano front caliper and fitting levers (see below). However, the brake pads would be at the limit of the calipers reach at 57 mm.

Will modern Shimano levers and calipers provide enough two-finger braking power to safely ride from the hoods?

At the rear I shall keep the current Weinmann centre pulls. These work well enough for the back. Lever compatibility is another question, see the SE question on similar Dia Compe brakes.

Parts: Shimano BL-R400 levers and BR-R451 long reach calipers. Both are super SLR

Aluminium rims 622-19, 24 mm outside width


What reach is:

The effective length of the arms of a caliper brake. This is measured from the centerline of the center bolt diagonally down to the middle of the brake shoe. Reach is commonly expressed as a range (allowing for the fact that the brake shoes are adjustable, typically over a 10-15 mm range.) For more information, see the article about caliper brakes.

From Sheldon Brown's knowledge base

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I got the Shimano BL-R400 levers for my bike and they work great with my Dia Compe centre pulls brakes so I see no reason why they wouldn't work with your Weinmann brake which is similarly designed.

Using the center pull brakes combined with the new levers provides ample braking power both from the hoods and the drops. I can't speak as to how well the braking would work for modern calipers.

That being said, the BR-R451 calipers are only "long reach" by modern standards. There are calipers with much longer reach available if you need them. The braking power shouldn't really be effected too much by the length of the caliper. A longer caliper arm will tend to flex more, but the arm on the BR-451 isn't even really that long. They have been designed by a quality manufacturer who would taken into account the longer arm and design the brake with the right type and amount of material to resist excess flex in the lever arm.

  • I've just measured again. I indeed need at least 65 mm of reach, ruling out the 57 mm Shimano calipers in the front (for which I have not a centre pull but a rubbish Weinmann side pull). – gschenk Mar 9 '17 at 14:24
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    Measure twice, buy once, I always say. 65 mm is quite long by modern standards, but there is stuff available like the Dia Compe DiaCompe 750 Centerpull brake caliper shown in the link on my post. These have been around forever, so there's a good chance you could pick up a set used for a reasonable price on ebay or similar websites. – Kibbee Mar 9 '17 at 14:35
  • It's what @criggie refered to a 'gaspipe steel frame'. But since it lasted for decades, it is not at risk to be a BSO at least. I've a knock-off of the centre pull at the back, it is a decent enough brake. But I've only one, and also no provisions to attach a centre pull to the front. It would require some harness attached slammed to a threadless stem. – gschenk Mar 9 '17 at 14:40
  • I've measured again, since I used a false definition of reach on an online shops webpage. I've added Sheldon Browns above. – gschenk Mar 9 '17 at 14:41
  • I'm asking product recommendation follow-up questions in chat: chat.stackexchange.com/transcript/message/35923564#35923564 – gschenk Mar 9 '17 at 14:49
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Since I asked my question some time has passed and I did upgrade my bike. The Shimano calipers would not fit, thus I went for Tektro. I summarized my experience for future reference:

Modern brake levers and calipers are indeed a great improvement over my old brakes. The front brake is more than strong enough for me to brake from the hoods.

modern brake levers on an old bike The geometry of brake levers does quite a lot for good braking from the hoods. Each of the bends of the lever has a purpose. At the bottom the lever goes a little outward, to let my small and ring finger rest on it. As I pull it in my other fingers slide naturally onto the lever, providing me a strong grip.

long reach calipers (55 mm to 73 mm) In addition, modern calipers have quite weak springs compared to old ones. This reduces the force needed for braking quite a bit. However, the long caliper arms reduce the force pushing the pads on the rim for a given torque. One cannot get as high braking forces with a long reach caliper as with a mid (up to 55 mm) or short (<45 mm) caliper.

To compensate for this I used much recommended (salmon coloured) brake pads. And I shall keep my rims meticulously clean.

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