Bicycle Mechanics - Shimano road brake isn't springing fully open

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mattkime
10-23-08, 09:28 PM
I'm working on a front brake from a 2005 Trek 1000 and its not springing full open. There is a little bit of squeaking from the collar around the spring. I suspect the next step is taking the thing fully apart, cleaning it, lubing the right parts and reassembling. Before I do that I thought I'd check here and see if anyone had better advice.

BikingGrad80
10-23-08, 10:25 PM
Probably needs to be overhauled, cleaned, regreased etc. There is an article on park tools.
Booger1
10-23-08, 11:14 PM
Could be the cable starting to fray also.

nitropowered
10-24-08, 05:38 AM
check your housing and cable. There may be corrosion in the housing. I overhauled a brake before because I thought it was the brake sticking (its still needed it) but in fact it was a badly corroded cable sticking in the housing.

Un bolt the cable from the brake and squeeze the caliper by hand and see if it is sticky.
mattkime
10-24-08, 03:35 PM
The brake springs back fairly well when its off the bike. it stops springing back properly when i place it back on the bike and tighten the mounting. do i need to take apart the the brake assembly and clean it? am i simply over tightening the mount? its really not on that tight.
DannoXYZ
10-24-08, 03:59 PM
The brake springs back fairly well when its off the bike. it stops springing back properly when i place it back on the bike and tighten the mounting. do i need to take apart the the brake assembly and clean it? am i simply over tightening the mount? its really not on that tight.Sounds like the pivot-bolt locknut isn't locked correctly to prevent the arms from getting pinched when you install the brake. You might also want to drip a drop of oil onto the spring where contacts the caliper-arm.

What model brake? Pictures?
bluenote157
10-24-08, 04:39 PM
I had some older dura ace calipers.. and the bushing/washers got so gunked up that under pressure they would stick like the OP described.
Panthers007
10-24-08, 05:00 PM
A brake -set that old deserves a full overhaul and new cables and housing. Do oil the new cables - not grease as they can turn to glue in the plastic or teflon inner cable-housing. Clean and oil all the parts. That should take care of them. Just think about doing this sooner this next time.
operator
10-24-08, 05:53 PM
A brake -set that old deserves a full overhaul and new cables and housing. Do oil the new cables - not grease as they can turn to glue in the plastic or teflon inner cable-housing. Clean and oil all the parts. That should take care of them. Just think about doing this sooner this next time.

No new brake cable and housings, and especially derailleur cable/housings need to be lubed.