Braking... Bad: Part 1

As you can guess from the picture, I have a slight problem with my forks.   I have been running my Sturmey Archer XL-FDD front hub with 90mm drum brake for about 2 years now without any issue.  This included many hard stops, one or two almost crashes, hopping off kerbs regularly and other general things town bikes get subjected to.   As I recently received some replacements for my TRP Spyre disc brakes which were recalled from my cyclocross/all road bike, I decided to put the extra set of compressionless cables that came with them to use on my town bike.



Immediately, the lever feel was a lot firmer, unlike before I was able to lift up the back wheel from heavy braking quite easily - I was able to finally do stoppies unlike before.  I figured previously when I had used conventional coiled brake cable housing, even with the brake lever touching the bar I could never lift up the back wheel, it was due to the housing compressing.  Increased braking power was definitely a good thing in London traffic.  However on the first evening on my bike returning from work I noticed that the steering feel a little strangely light, I looked down and was aghast that the fork was bent!  As you can see from the photos, it's quite apparent that the force put through the reaction arm overcame the elasticity of the fork and bent it back right where it attaches.



The paint is cracked around the area where the reaction arm attaches, the fork is also twisted from the uneven load put on the legs, all this from a few stoppies!  Please keep in mind that I weigh under 70kg as well so there was no real extreme conditions that caused this to happen.  I figure though that the fork was designed for rod/caliper brakes originally which would have focused all the braking force in the crown not midway up the left fork leg so this isn't a complete surprise.  

As I have no intention of going back to caliper or rod brakes, I think my only real long term option is to replace the fork with one that is more suitable.  It's a real shame as these are the original forks, I even have the key that fits in the fork lock too!  To this end I've ordered a fork with a proper drum brake reaction arm which should be strong enough to handle the force from the drum brake.  As this is a daily driver bike which gets ridden everywhere, reliability and my safety are paramount so I think this is the right choice.  Stay tuned for more!



6 comments:

  1. Gah! That sucks ): I've heard similar stories with people retro-fitting disc brake tabs to forks. Stay safe!

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  2. Oh shit! I've been watching you and your blog since almost it was made,but didn't expected this to happen! Problem is, I just recently got a 90mm drum brake hub too and was thinking about laceing it into a 28/622 wheel too!The bicycle to wich I intent to mount it is a 1980's CILO road bike wich was intended for "normal brakes"...
    Could the fork end up like yours?! Now you got me thinking even more, maybe I SHOULD change the fork too , must be a tradeoff when a cyclist wants almost maintenance free brakes+ good stopping power almost disc brake capabilities! Keep adding information on your drum brakes ,it's very usefull for many cyclists! Cheers!

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  3. Hey, if you read part two you can see which fork I chose. I ended up breaking my frame as well due to using compressionless housing with the 90mm drum brake as well: http://smutpedaller.blogspot.co.uk/2014/03/an-unfortunate-end.html

    Although I suspect this may have also been because the frames Raleigh made in that era were a little lacking in build quality, I was surprised how easy it was to break apart the brazing on the original forks. But yes, I would definitely recommend trying to find a drum specific fork, if you can. The one I got was from http://www.dutchbikebits.com/ The funny thing was that the fork was perfectly fine for a few years, it was only when I fitted compressionless housing I was able to brake really quite hard and that was enough to stress out the fork. Live and learn...

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  4. I would recommend the 70mm drum brake. Still plenty powerful. The original Raleigh forks were certainly not designed for drum brakes, and the compressionless brake cable outers probably finished the forks off. Who'd have thunk it that the slight give in the coil brake cable outers actually provided a tiny amount of brake modulation?

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