Bicycle Mechanics - new guy question
Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.
new to the forum, just started riding to work on a daily basis. Situation- when i shift gears there seems to be a lag between the input and the actual shift. I will attempt to shift while pedaling and nothing, then click and clank it jumps into gear. I have had to shift, stop pedaling, and start pedaling again to not get the jarring shift. I am assuming the cable is stretched but am not sure. I ride on the road which is flat, it is an older GF wahoo (2005 ish). Looking for some advice, am familiar with tools and would rather learn to fix than pay to fix. Thanks...........
03-08-11, 04:02 PM
welcome to the forum. First things first ,make sure the drivetrain is clean , then if the cables are stretched , loosen where cables are connected to the derailers pull the cable tighter and tighten the hardware. makes any adjustment thou the adjustment barrel at the derailers or somewhere on the frame. If this doesn't work then replace the cables and housing are in order.
03-08-11, 04:05 PM
If it's slow to shift to a larger rear cog, then it might be as simple as adding some cable tension via the barrel adjuster. Parktool.com and bicycletutor.com are two of the numerous sites that explain these adjustments.
If shifting is hesitant in both directions, it's possible the interior of the cable housing ("liner") is worn or crudded up. The liner in the short section of housing nearest the rear derailleur is particularly prone to wear (due to its tighter loop) and contamination (due to its location).
03-08-11, 04:39 PM
Even at the best of times bicycle shifting is not "light switch" fast. The higher end components are faster but they often still have a quarter to half turn or so of the cranks before things begin to happen and another half or so before things are done and settle down. During that time you want to keep pedalling but greatly reduce the force used so you minimize the clunking and snapping that occurs when you shift under full load.
First step is to set up the cable adjusters so your shifts both up and down are equally quick. That's done by adjusting the barrel adjuster on the rear derailleur where the cable housing stops. The housing fits into that barrel adjuster. As noted it's all shown at www.parktool.com/repair (http://www.parktool.com/repair) . Just hover your mouse over the rear derailleur at the rear of the bike and then click.
If the bike is older it would not be a bad idea to treat it to a set of new cables and housings for all of the brake and shifting systems. Over time the cables cut into the plastic low friction liner of the housing and when that happens it tends to bind and add a lot of resistance to the systems.
Once the new cables and housings are on you can adjust the cable tensioning barrel adjusters found at mountain bike levers and at the rear derailleur. The idea is that you want to even up the speed for up and downshifting by centering the jockey pulley cage of the derailleur with the gear currently selected.
If the rear derailleur has taken a few good thumps or falls over it's life then there's also a good chance that the derailleur hanger on the frame is twisted. To check and correct that will require a trip to a bike shop since the tool used for checking the alignment is not a common shop item.
03-08-11, 04:41 PM
First of all is the rear slow or the front. You say you are new so I can't assume you know that the front does take a little time to shift. Depending on what components you have the back can hesitate also. Is the delay consistent in terms of how far the cassette has rotated?
03-09-11, 01:58 AM
Is your bike red?
Red bikes are prone to bad shifting.
Powered by vBulletin® Version 4.1.12 Copyright © 2013 vBulletin Solutions, Inc. All rights reserved.