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Old 05-03-08, 03:55 AM   #1
cdotbois
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Clamp Lever Too Tight = Poor Lever Return. Why?

I tightened some non-aero brake levers down on some handlebars, and then I noticed the front lever had a lot more resistance as a result. I thought the caliper return springs would make it a nonissue after I set them up, but it was only somewhat. The levers wouldn't complete return consistently. So I undid the cabling and loosened the lever clamps some until it felt "normal" again, put everything back, readjusted, and all better.

Apparently I shouldn't overdo the tightening of my hoods. I didn't think I was going overkill, but maybe I was. After I loosened the one, the hoods still felt pretty secure.

I was wondering, though, why clamping down too much deteriorates the spring return of the lever. I guess the clamp bolt does travel through the body of the lever so maybe I compressed something, which doesn't sound like a good thing to be doing at all. Anybody actually know and wants to enlighten me on the secret inner world of brake levers? And how tight should I be tightening those things until I know they won't slip while climbing Everest?
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Old 05-03-08, 06:55 AM   #2
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the clamp bolt should be 50-70 in-lbs i can only assume you compressed the plastic and deformed applying too much friction to the lever.
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Old 05-03-08, 07:04 AM   #3
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You had probably tightened the clamp enough that you deformed the lever housing a tiny bit. That can put the pivoting parts in a bikd and not release smoothly.

The same thing can happen with shifters. If you try to install a Rapid Fire shifter over the bend of a riser handlebar it won't work.
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Old 05-03-08, 01:38 PM   #4
cdotbois
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Cool deal. 50-70 inch lbs isn't that much. It's hard for me to judge how much I need to tighten one little screw to one little clamp that's supposed to hold up to whatever pushing and pulling I might exert on it. Now I know. Thanks.
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