Slight shifting problem.
#1
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Slight shifting problem.
This morning on my way to school. I noticed that when i try to shift to a lower gear it takes a while for the gear to actually shift. However, when i shift to a higher gear it's almost instant.
Could this be related to a RD cable tension adjustment??
What do you think???
Could this be related to a RD cable tension adjustment??
What do you think???
#2
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I would turn the barrel adjustment down a bit. When I say down I mean to slacken the cable ....turn the barrel "in" one notch at a time and try it.
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New cables and housing.
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What do you mean when you say shifting to a "lower gear"? If you are talking about shifting to a smaller cog that is actually a shift to a higher gear. When shifting to a smaller cog the derailleur spring is pulling the cable from the shifter. Dirty or corroded cables and cable housings cause excess friction and sluggish shifting. Always replace the housings when replacing the shift cables. The short housing just before the rear derailleur is often the location of excess friction due to the short radius bend in the housing. And the short housing is closer to the sources of dirt, and water.
Al
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Poor suggestion here....and would only be likely if the 'hesitation' was happening while shifting to a higher gear (smaller cog). In that case, the shifter would be 'letting out' cable but the R/D spring tension wouldn't be strong enough to pull the cable through the housing against the friction.
In the OP's account, he was having a hesitation on downshifts (to larger cogs) which relies on direct cable pull by your finger's pressure on the shift lever, a force that would be strong enough to overcome the friction in a worn out cable/housing. The simple fact that the OP mentioned that the bike is immediately shifting to higher gears (smaller cogs) tells me that there is NO cable friction problem.
I believe the correct answer to this question would be to actually tighten cable at the barrel adjustment a bit. Because it is hesitating on shifts to larger cogs, the cable pull isn't adequate with a click of the shifter, and requires more cable to be 'pulled in' to achieve a clean/quick shift. TIGHTENING the cable at the barrel adjuster will accomplish this.
Without over thinking this, you can simply put the bike upside down and shift it while pedaling (if you don't have a service stand). Turn the barrel adjuster on the R/D one way two clicks and shift up and down the cassette, if the condition gets worse, return the barrel adjuster to the original position and then go two clicks the other direction. You can trial and error this until you get a more familiar idea of how the barrel adjuster moves your R/D.
This is basic bike tuning, and will be very valuable for you to know. Take your time, be patient and work though it until you understand what's going on. Pretty soon you'll be recognizing tuning 'inefficiencies' on other's bikes in group rides and wishing you could just roll that adjuster for them a few clicks in the needed direction.
-Jeremy
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Don't think I've met anyone who describes shifting their car from 4th gear to 5th gear as "shifting to a lower gear."
Just saying. I realize that this can be confusing for some, especially if phrases are used like "shifting up" or "shifting down" But to say shifting to a lower gear leaves out any reference to what direction on the cassette your chain is moving and seems to me like pretty plain language. Thats why I felt confident enough in my response to go into that detail. Hopefully he'll post back and clarify for both of us.
-Jeremy
Just saying. I realize that this can be confusing for some, especially if phrases are used like "shifting up" or "shifting down" But to say shifting to a lower gear leaves out any reference to what direction on the cassette your chain is moving and seems to me like pretty plain language. Thats why I felt confident enough in my response to go into that detail. Hopefully he'll post back and clarify for both of us.
-Jeremy
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did you check your limiter screws on the rear derailleur? you may need to loosen up your low range limiter so you can make it onto that gear. as you may not NEED new shifter cables and housings, they do improve things a bit, are a common source of problems and are cheap enough. this i will asume you know what your talking about when you say shift into a low gear. obviously inspect your deraillur for any mechanical hangups as well, but my guesss is limiter screw then cables and housings.
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I hear what you are saying and coming from an automotive mechanic background I agree, but these are bikes. Most people say lower/smaller to mean from say a 15 tooth to a 13 tooth cog. Thus, that being the assumption, I'll stand by my recommendation.
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Twist that barrel adjuster about 1/2 turn CCW. If tunnelrat and I are right that'll fix it.
#11
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That's my guess too assuming that it was ever right. Cables frequently "stretch" a little and require a little additional tension to restore crisp shifting. Cables never shrink.
Twist that barrel adjuster about 1/2 turn CCW. If tunnelrat and I are right that'll fix it.
Twist that barrel adjuster about 1/2 turn CCW. If tunnelrat and I are right that'll fix it.
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I adjusted the barrel counterclockwise and shifting has been restored to normal. Thanks for the help.