Derailleur adjustment on new bike

**jrenaut** · 01-23-2013, 08:10 PM

So, my new bike has about 175 miles on it. I know that cables stretch for the first bit, and you just have to wait until they're done, then you can adjust and ignore things for a while.

However, after this many miles, should my rear derailleur still be getting way out of adjustment every 5-10 miles or so? I'm definitely getting better at adjusting it myself (Proteus, where i bought it, is a great shop. However, it's a 20+ mile round trip, so it's difficult to get out there for this kind of stuff). But when I get it pretty close to where it should be, and then five miles later it's shifting badly, or slipping gears when I'm out of the saddle and pushing hard - that seems wrong to me.

Is this to be expected? Or is there something wrong?

**DismalScientist** · 01-23-2013, 08:20 PM

Cable stretch has less to do with miles than how many times you yank on the cable.
Also, with more cogs on the cassette adjustments are more finicky.
Just stick it in friction mode and wait longer between tightenings of the cable.

**jrenaut** · 01-23-2013, 08:31 PM

It's a 10 speed rear, so tons of cogs. What is "friction mode"?

**thecyclingeconomist** · 01-23-2013, 09:17 PM

"...still be getting way out of adjustment every 5-10 miles or so"

Something's off. Even normal cable stretch leads to very gradual miss-shifting over the first 200+ miles. However, what might have occurred is that the housing ferrules weren't seated correctly, so you can get a LOT of change in the effective length of the cable from those getting set into place. But over 175 miles, even that should've worked itself out quite rapidly.

I'd take it in. Something is slipping. (You didn't provide details on the drivetrain: what kind of shifters? etc?)

**krazygl00** · 01-23-2013, 09:59 PM

Originally Posted by jrenaut

It's a 10 speed rear, so tons of cogs. What is "friction mode"?

He's being all retrogrouchy

Friction mode would be with downtube shifters where you could switch from indexed shifting (detents which allow the shifter to "click" into place) to friction shifting where shifter movement is smooth for the whole range allowing infinite adjustment. It's like digital versus analog, or like a fretted bass versus fretless.

**bobco85** · 01-23-2013, 10:09 PM

Definitely take it in. Hopefully it's just something minor, since it's a new bike. Maybe the screws are a little loose in the derailleur? That's my guess.

Originally Posted by jrenaut

It's a 10 speed rear, so tons of cogs. What is "friction mode"?

Friction shifting involves changing gears by moving the shifter (just a lever) which will pull the derailleur left/right to another gear. The lever moves smoothly and does not "click" into place. You can feel (and hear) the "friction" when the chain is not directly on a cog and then you just need to adjust the lever until it feels (and sounds) smoother.

The type of shifting most people are used to is index shifting where the derailleur moves a set distance every time you "click" the shifter into a new gear.

Here's an analogy to help (this is how I understand it) - Friction shifting : index shifting :: manual drive (cars) : automatic drive (cars)

Sources:
http://sheldonbrown.com/gloss_e-f.html (scroll down to Friction Shifting)
http://en.wikipedia.org/wiki/Shifter...ction_shifting

**thecyclingeconomist** · 01-23-2013, 10:35 PM

If he's got a 10-speed rear end, it is HIGHLY unlikely that he's got either downtube shifters, or time-trial shifters that have the option to run in either indexed or friction mode.