PDA

View Full Version : 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.:rolleyes:

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
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.


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_(bicycle_part)#Friction_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.

TwoWheelsDC
01-23-2013, 10:52 PM
His bike is 2013 Tiagra, so no friction shifting.

jrenaut
01-24-2013, 08:35 AM
Thanks, all. Yes, Tiagra with 10 in back. I'll take it in.

DismalScientist
01-24-2013, 09:46 AM
Sorry, I thought :rolleyes: is the international smiley of sarcasm. :rolleyes:!

baiskeli
01-24-2013, 10:06 AM
He's being all retrogrouchy :)

A new word for the forum dictionary!

Greenbelt
01-24-2013, 02:59 PM
Is it just me, or do new chains also sort of have a break in period? For example, even on my very well-worn bikes, often when I have a new chain installed, the shifting goes a little whack after 50 or 100 miles, then after some twiddles, seems to stabilize after 200 miles or so.

PS. Jon, aren't you due for your warranty tune anyhow, or did you already do that? The shop is open late tonight (until 9pm) for potluck if you want to ride out there with me (and maybe take Metro home?) -- Ben and Anthony and Johnny are there tonight and can probably do at least some adjustments on the spot. You'd have to put on your cross tires... -Jeff

jrenaut
01-25-2013, 08:51 AM
This morning, I left the house on the way to Friday Coffee Club. I had gone less than a mile when suddenly my bike was a 3-speed. Absolutely no response from the rear derailleur. I stopped at the bike shop, happily only a few blocks away (The value of having a bike shop or two along your normal commuting route can not be overstated). Turns out the derailleur hanger is bent. They got it adjusted so that the bike would shift again, which lasted maybe 2 miles, and then it went out again. Pulling on the cable got it to shift again, but it looks like a trip to Proteus is in my weekend plans.

Makes me feel better that my complete inability to get the derailleur adjusted well wasn't actually my fault.

Dirt
01-25-2013, 09:13 AM
While they're working on it, have them check that the cable housing is okay and that the derailleur isn't messed up. Sometimes those things happen together. They can all contribute to a shifting problem.

jopamora
01-25-2013, 09:24 AM
I stopped at the bike shop, happily only a few blocks away (The value of having a bike shop or two along your normal commuting route can not be overstated).

What LBS in DC is open at 8am on a weekday? Maybe your bike didn't like those compromising pictures you posted.

jrenaut
01-25-2013, 09:32 AM
The Bike Rack (http://thebikerackdc.com/) at 14th and Q NW is open 8-7 Monday through Friday, 10-6 Saturday, 10-5 Sunday. Good shop, though their selection of bikes tends towards road racing and cruisers more than versatile commuters.