new SRM part for Carbon

PSUcycling

has anyone seen this yet?

http://www.competitivecyclist.com/z...PRODUCT.ID=3402

helps in mounting the power sensor on carbon frames.

They want $50 for it, but i made one last night for about $10 and works great. If anyone is interested i can post pics of it.

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Chann McRae Cycling Coach
Velossimo Racing Team
Racing Blog
john@cmcoaching.com

RoadBikeGuy

I saw that. While a decent idea I think $50 is too high for what you get. I was toying with the idea of trying to fabricate something simliar. I'd be interested to see any pics you have. Perhaps dimensions too if you have them handy.

Zach-dk

Please do

PSUcycling

you'll need some small pieces of plastic, and i used a 2 part epoxy made for plastic that i bought a the local autozone ($4).

I placed it under the plastic cable stradle becuase you only have one hole to mount the bracket to, if placed on top it will pivot, and the bolt can't be screwed down tight enough to keep it still. The tension from the cables helps keep the bracket very rigid.

There are 2 parts to the bracket.

1) the plate: a thin flexible piece of plastic, roughly 33mm x 30mm, the key measurement you'll need is the distance from the mounting bolt (on bike frame) to the edge of the srm. (for reference, mine was 25mm from the hole to the opposite edge, giving me about 1mm gap to the SRM itself)

2)the block: another piece of plastic 9x9x30mm.

i first mounted the plate to get an idea of how far over to glue the block.

then i epoxied the SRM sensor bracket (black peice) to the block i made, then epoxied both of them to the plate making sure to have about a 1mm gap.

note: it would have been easier just to mount the SRM bracket right to the plastic plate, but the sensor mounted there would only read RPM's. I had to raise it up that much to get it to pick up the power signal.

note2: Make sure to sand and clean all mating surfaces or the epoxy may not hold.

you can see in the pic i was able to run the sensor wire under the plate to keep it out of the way of moving parts and der. cables. In the 3rd photo you can see the old mount, this was prone to shifting and would lose the signal about once a month.
(that happened once in the middle of a stage race and i reached through to move it and i acutally popped the sensor of the stock bracket, i eventally snapped it back in and was able to get back into the pack before the next climb!)

pics:

__________________
Chann McRae Cycling Coach
Velossimo Racing Team
Racing Blog
john@cmcoaching.com

RoadBikeGuy

Thanks for the info PSU. I like your version better than the one shown at Complete Cyclist.

Woofer

Nice job.

It seems to me that the SRM should come with a hot glue gun because on the three frames on which I use it, it's impossible to mount correctly without using some sort of extra artificial support system.

PSUcycling

thanks guys.

i think the problem is that the SRM design is a few years old, back when carbon frames didn't even really exist. It works fine on my aluminum-framed TT bike, but they should redesign the mount.

I think with some good TIG welding you could fab a mount using the spacer between the frame and BB cup (the one used to keep the chain from cutting into the carbon if it falls off..)

__________________
Chann McRae Cycling Coach
Velossimo Racing Team
Racing Blog
john@cmcoaching.com

Woofer

I have different issues, use it on two track frames so there is no cable guide on them, and one has what looks like an inverted shark fin where the cable guide goes. The other frame is cross so there is lots of space between the sensor and the white disc anywhere I could mount the sensor conventionally.