Tektro's R538 long drop callipers are aimed at big-tyred tourers and town bikes and they're a good quality unit with a couple of nice touches. The bolts get rusty quickly, and the pads are a bit scratchy, but they're pretty well-made for the money.
The R538s are a forged Aluminium dual pivot affair, and a fairly standard design with long drop arms that accomodate pad heights of 47-57mm, ideal for tourers and other bikes designed to take a big tyre. My set have been fitted to a town bike with a Kinesis training fork and full 'guards, and they're just the ticket in terms of reach. At 164g a wheel they're not heavyweights either.
The quick release has been redesigned on these brakes to allow a wider opening to remove your chunky tyres, and it works really well. The brakes will easily accomodate larger rubber, I've had up to 35mm tryes in the frame with no problems and they could go bigger depending on where the pads are set in the arms.
The pads themselves are probably the worst bit of the R538s - they feel cheap, hard and scratchy. They still stop you, but you'll be glad when you've worn through them so you can fit something a bit less noisy - I've swapped them for a set of Ashima's Pro Gs and they've improved the feel no end. My other main gripe is that a month of wintry road grime has already started to rust the bolts. It hasn't affected the performance of the brakes but they don't look so good any more, not that that's a major concern with a town hack.
Tektro have a reputation for offering good value braking kit, and the R538s are no exception. In terms of performance they're not outstanding but they do the job and they're a good option for a workhorse or tourer.
road.cc test report
Make and model: Tektro R538 long drop brakes
Size tested: Black
Did you enjoy using the product? Great for a town hack or tourer
Would you consider buying the product? Yes
Would you recommend the product to a friend? Yes
About the tester
I usually ride: whatever I\'m testing... My best bike is: Trek 1.5 with Ultegra 6700
I've been riding for: 10-20 years I ride: Every day I would class myself as: Experienced
I regularly do the following types of riding: time trialling, commuting, sportives, general fitness riding, fixed/singlespeed, mtb, Mountain Bike Bog Snorkelling, track