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Trek420
07-28-2004, 07:25 PM
ok, it's a new bike. Had this problem on the AIDS ride (can't get into granny gear...once in, can't get out) but also frequent chain suck, chain just drops off the rear cog.

I'm careful not to cross gears. I've just had the bike tuned, sort of a post ride check up, I clean and lube the chain frequently....it's new campy record...why me? ;-) never had this probelm with Ultegra.

pedalfaster
07-28-2004, 09:53 PM
Sometimes I think the bike-gods just laugh at us. I am have all kinds of problems with a new Dura Ace chain/cassette. Like you never had a problem with Ultegra. Grrrr.

So are you actually dumping the chain into the spokes?

It sounds so obvious, but have the LBS check the limit screw on the rear der. again.

If that doesn't help, perhaps it's time for some sort of "bike voodoo". Burn photos of Mario Cipollini whilst covered in Phil Wood grease and chanting the Campy gruppos at the next full moon or something. Can't hurt.

:D

Trek420
07-28-2004, 10:12 PM
I'm not sure of the term but often when I go into the granny sometimes the chain jumps off the front, I'll be padaling and suddenly, nuthin, spinning in air. My lbs says there's a deedly-wob they can put that "catches" the chain so that doesn't happen. We've both got top of the line parts...should work perfectly, eh?

I'll try the burning sage n' pictures of mario thing, can't hurt, cheaper too. ;-)

Or train so don't need the granny? Nah...

g'night.

Irulan
08-20-2004, 07:29 AM
Having studied chain woes excessively this summer, including ghost shifting in the back and chain suck in the front...

-check front derrailler clearance over big chain ring. If it's even a mm or two too high, it can throw your chain.

-are chain rings installed correctly? Not off a 1/4 turn, not backwards,

- bent chain ring or front derailleur?

- chain suck, when it actuall gets "sucked" between the frame and the chain rings, and other shifting problems can be caused by shifting under load, operator error

-is the chain worn? Uneven wear between chainrings, cogs and chain can cause all sorts of problems. Replace your chain the very second it starts to show stretching.

for rear derailler problems, check that the hanger isn't bent and that the rollers line up exactly with the largers cog in the back when you are set for the lowest gears... you might have to to take the chain off to check this.

Irulan

Trek420
08-20-2004, 02:09 PM
Irulan wisely wrote"
-is the chain worn? Uneven wear between chainrings, cogs and chain can cause all sorts of problems. Replace your chain the very second it starts to show stretching.

I'll check all the other things, the chain is brand new, only 765.8 miles on it (I biked to work so just leaned over and just checked!)

Irulan
08-20-2004, 02:32 PM
after the great McCall epic I was having all sorts of drive train unpleasantness. We had a pro mechanic along, and in a 30 seconds he told me, deraiiler was to high, rear hanger was bent, middle chain ring was bent and put on screwy... amazing

Irulan
08-20-2004, 04:49 PM
oh yeah, I was told to replace a chain every 500 or so? Have you had it checked with one of those do-hickey gizmo thingys?

~irulan

Trek420
08-20-2004, 05:59 PM
Irulan advised "Have you had it checked with one of those do-hickey gizmo thingys?"

you mean the chain...uh...whatchamakalit? not the wrench, the thingamabob that checks if your chain has stretched? are we tech savy or what?

yes, at least my LBS did recently, could have missed it. I thought I was just forgetting that I don't have one lower gear but then it happens when I'm NOT in the lowest available gear, and usualy when I start going uphill.

my bike club is starting to think i throw the chain off to avoid doing hills ;-)

Adventure Girl
08-20-2004, 09:20 PM
Originally posted by Irulan
Have you had it checked with one of those do-hickey gizmo thingys?
Originally posted by Trek420
you mean the chain...uh...whatchamakalit? not the wrench, the thingamabobTech Talk!! Only on a women's forum would you find technical jargon like this!! :D

Irulan
08-21-2004, 06:09 AM
ok, if you are so smart what IS the proper name for that chain stretch measuring device? ( there, is that better? ) ;-)
http://www.parktool.com/images/tools/CC_3.jpg


What I learned about it that I thought was interesting is that there are two measeuremnts on it, the .75 and the 1.0. So depending on which side of the CHAIN CHECKER you use to measure, you'll either tome ok, a a litle bit stretched or a lot. IIRC, the .75 side is for aluminum chains.

Anyway, no one has really discussed operator error as a cause for chain suck. As much as I HATE to admit it, I'm convinced that maybe 50% of my chain problems were/are due to shifting under load...Thowing the chain down a ring while madly pedaling up a grade, instead of just laying off for a second or two for smooth shifting...

Irulan

Trek420
08-21-2004, 06:22 AM
Adventure Girl quipped "Tech Talk!! Only on a women's forum would you find technical jargon like this!! :D"

Yeah, but i bet the forum on teamtestosterone.com doesn't have the fashion talk we do!

pedalfaster
08-21-2004, 06:31 AM
Yep. See all kinds of bad-shifing habits. And have to admit to them sometimes myself when I start to get tired and wonky:p

Like "Why is it soooo hard to get up this climb?" Then looking down and realizing I'm in the big chainring and cross-geared. Oh. duh. grrrrr.

I knew my recent shifting woes were gear-related (no pun intended) though, because in the past in order to throw the chain back up onto the chainring, all I had to do was shift UP while pedaling. This dropped chain was of the "stuck down in the frame and won't come back up with out manual manipulation" variety.

I had done a bunch of work to the bike (new chain, cassette and cables...). I'm pretty sure my front der. was moved(a different kind of operator error) and no longer in the optimal position. Playing around with it, I can now shift without dumping the chain, but the trade-off is a bit of chainrub when lower on the cassette. I also noticed a lof of "slop" in the pivots. I've crashed a few times and chances are good it could be slightly bent as well. Perhaps after 8+ years its actually time for a new front der.???

Darn, I hate spending $$$ on un-sexy stuff like new derailleurs!

The mountain bike is asking, make that begging, for a new drive-train and shifters (10 year-old LX!) as well.

I'd rather buy pretty new bar-tape and some schwanky new bike shoes.....

Irulan
08-21-2004, 06:40 AM
what I was told by the pro mechanic is that you should only have about 1 mm of clearance between the big ring and the bottom of the front deriailler. You might play with that setting, it's free. All you have to do is loosen the screw that holds the derailler to the frame, and most likely pound on it a bit to lower it. You'll want a real accurate measuring device (we used a caliper) to check the clearances. Changing that seemed to help my front shifting woes quite a bit.

Irulan

maryellen
08-21-2004, 02:55 PM
I feel so together! I recently had a bout of phantom shifting -- cured by a woman (yea!!) bike mechanic adjusting the tension on the rear derailleur. Even so I decided to buy a "chain checker" as I somehow have the idea that I may be hard on the chain--new rider, wild shifter, etc.

Got to admit I haven't used the chain checker yet, but I will soon!

Trek420
08-21-2004, 03:40 PM
pedalfaster wrote "I hate spending $$$ on un-sexy stuff like new derailleurs!"

Hah! deraileurs are not un-sexy, it depends on the deraileur.

Troublesome as my shifting is my new bike has Record, the deraileurs are pretty, and black and carbon Italian and... :p

Adventure Girl
08-21-2004, 04:25 PM
Originally posted by Trek420
Hah! deraileurs are not un-sexy, it depends on the deraileur.
Spoken like a true Campy Gal!!:D I am an un-sexy Dura-Acer, myself. DAMN, that Campy is beautiful!

Trek420
08-21-2004, 05:28 PM
Adventure Girl sayz "DAMN, that Campy is beautiful!"

Dura ace is NOT sexy? Isn't that Shimano's best of the best? As an ex-ultegra gal I'm crushed...

Trek420
08-29-2004, 12:33 PM
Irulan wrote "no one has really discussed operator error as a cause for chain suck. As much as I HATE to admit it, I'm convinced that maybe 50% of my chain problems were/are due to shifting under load..."

Irulan, you're right, you're always right, you're never wrong ;-)

...just back from a 30 mile group ride that I've had chain problems on in the past. Cleaned my bike the night before so it's not that. (forgot to pump air into the tires..doh! One of the Velo Girls had a floor pump, note to myself put one in the car) Today's goal "I'm NOT going to throw the chain."

Someone wrote "good cyclists shift with their eyes", funny thing is I hardly ever have problems on the big hill up to Pulgas Water Temple, it's after that. This time as I approached my nemisis hill I picked a gear that "I can live with this to the top". Like Dubya says I "missunderestimated myself" but rather than change under load just figured when I get to the top if I have anything left I'll drill accelerating over the crest. Which I did, so I did.

bikerbarb
02-24-2005, 05:05 PM
Hey, I just found out what that is! I bought a new Jamis Aurora bike last spring. I have had problems all along with the chain siezing when I shifted to the lowest gears. While on a tour this summer two different mechanics tried to fix it, playing with the front derailleur. I repeatedly took it back to the shop only to be abused by the macho jerks telling me I didn't know how to ride the bike. It now has 1700 miles on it. I took it a couple weeks ago to a Trek selling shop that did work on my daughter's bike and they not only diagnosed it, but contacted the manufacturer who sent--for free-- new chain rings! That was the problem! They even told the bike shop owner to put a new chain on it too. These chain rings are aluminum and better quality than the originals. The key to the diagnosis was the chipped paint from where it was being sucked back up into the chainrings.
I'm thinking about what to go back and tell the macho jerk. Not only is he not as smart as he thinks, but his manufacturer is better than him. And he lost a customer.

Trek420
02-24-2005, 06:31 PM
wow, forgot about this one. I rarely have this problem now , the Campy has broken in but sometimes if I haven't cleaned the chain (and I'm good about that, my one bike repair skill) it'll do it or the above and afore mentioned operator error, shift too low, no gears left....man I miss Flightdeck ;-) :cool: :) :rolleyes: