graytotoro

Hi all,

So I ride a 2009 Specialized Rockhopper as my primary bike. It's been good and has taken the all the abuse I can heap on it, but there's been one thing that's been bugging me, and that's the front derailleur.

It's the base Rockhopper with the Altus FD. It has no problem shifting 2-3 and 3-2, but it's the 2-1 with or without the 3 that has the most problems. No matter how I ride, it always jams up and the chain ends up hitting the chainstay and tearing more paint off.

At first I thought it was because I shifted too quickly; I would either hold the trigger too long or my glove would contact the shifter. So then I tried it in a more smoother setting and it still didn't work. I tried the Sheldon Brown trick of maintaining a constant pace and I don't think it helps.

So what am I doing wrong and what should I tell the LBS about?

This seems to go away if I backpedal shortly after it "kinks". The chain has no stiff links and it's properly lubricated. It is due for the 90 day checkup, though. Could the cable stretch be part of the reason?

Much thanks for your help.

reptilezs

sounds like chain suck, keep the chain lubed but just bring it into the shop for the 90 day checkup and tell them not us

LarDasse74

+1. Sounds like chainsuck.

Take it back to the shop and tell them you are having chain-suck when shifting into the small chainring.
Generally chainsuck is caused by wear on the chainrings, made worse when the chain is not worn.

Read this article.
https://fagan.co.za/Bikes/Csuck/
(referenced from Sheldonbrown.com)

Retro Grouch 

I'm going to disagree about it being "chainsuck". chainsuck is when the chain rides up the backside of the chainring and jams against the chainstay.

It sounds to me like you have a simple case of overshifting the granny. That's a front derailleur adjustment. The fact that you're having (lesser) issues with shifting in the other rings confirms my thinking.

Since this bike is so new I agree with the concept of taking it back to wherever you bought it. Tell them about ALL of the problems that you're having and suggest that they redo the front derailleur installation starting at the very beginning. Front derailleur adjustment - if you're having problems, isn't the first tuneing task that I'd suggest for a new bike machanic.

graytotoro

Ok, so I've taken it to the shop and they've told me that the chain is stretched. Badly. They can install a new chain w/o labor for $20. Do I go for this? The bike does have less than 200 miles and I keep it indoors and well-lubricated.

Edit - I worded one of the sentences incorrectly. The labor is free.

LarDasse74

200 miles is pretty short to wear a chain significantly...

And if it is worn badly, there is a chance that changing the chain and not changing other worn components (esp. rear cogs) will make the drivetrain skip badly under load.

graytotoro

Ok, it wasn't "badly" - I must have been thinking of something else. So do I go for it? Or is there something deeper that needs repair?

Another edit - I'm a 170-80 pound person who rides on the mostly middle/big chainring and 2-3-4 on the rear. I don't really use the granny and I mostly rely on the middle to get up steep hills. Did doing that put massive wear on the chain/drivetrain and how do I prevent this in the future?

LarDasse74

The symptoms you described sounded to me like 'chainsuck,' or the chain following the chainring around and getting jammed between the chainring and the frame. Chainsuck is usually caused by a worn out chainring and a newer chain, not a worn chain and new chainring.

I am a little suspicious of the LBS advice - have you measured the chain yourself? If you hold a ruler up to the bottom run of the chain (between the bottom of the chainring and the rear derailleur), the length of 24 links (fron centre-of-pin to centre-of-pin) on an unworn chain should be 12 inches... if the length of 24 links is 1/16" longer than 12" then the chain is worn. If this is the case, you shoudl rethink your lubrication strategy as a chain should not wear out in 200 miles.


If 24 links are not much longer than 12", chain wear is not the problem and you should probably not take advice from the same guy at the bike shop again as he is possibly completely full of carp, or ignorant.

graytotoro

I haven't measured the chain as it didn't occur to me that it was the case. I just thought the dérailleur needed tuning.

But I did try to keep it lubricated - I would re-lubricate the chains after ever wet-weather ride. I didn't do anything in the last 4-5 weeks, but as I didn't do that much riding (about 3 rides), I don't think it'll be that destructive.

More importantly, do I take them up on their offer?

cny-bikeman

A note on new bikes.

When you first start to have a problem take it in as soon as possible. The 30/60/90 days is (or should be) an adustment period, not a time you wait to arrive before having a problem attended to. Anything during that period that you have concerns about is generally covered, whether you have to make 1 visit or 10 (at 10 you have a lemon - bike or shop!). If you wait it will be less and less clear how much of the problem was with the bike/assembly and how much with riding it while out of adjustment, and problems will be harder to fix.

Finally, even if nothing seems to be wrong always take it in near the end of the period. It's normal to need readjustments after break-in, and there are plenty of things you may not notice or be aware of.

graytotoro

I would, but I was at school (I do everything on this bike) 60 miles away so it was a bit difficult to bring it back.

LarDasse74

Measure the chain first. If 24 links measures 12 1/32" or less then your chain is not worn and the guy at the LBS is either stupid or bullshi++ing you. A new chain will make chainsuck worse, if it is chainsuck.

joejack951

A stretched chain in 200 miles is BS. Complete BS. Sounds like the shop just feels like selling a chain. Chains don't miss the granny ring because they are stretched. They miss because the front derailler low stop screw is set too far inward. It's an easy mistake to make and a dead simple fix so I'm not sure why the shop doesn't just do it for you. It would literally take all of 30 seconds to adjust. If taking the bike to the shop is a hassle, go to www.parktool.com and read up on derailler adjustment. It's relatively easy to do especially if most of the shifting is correct. You'll likely only need to turn the inner stop screw in slightly and not have to touch anything else. A word of caution, don't blindly start making adjustments to the derailler. If you are unsure about which screw to turn or how far to turn it, ask first or else you'll have to start from scratch to get things back in working order.

Don in Austin

I can't imagine owning a bike and not learning how to adjust the derailleurs. I carry a 16/1 tool in my back pocket and if I don't like the way my bike is shifting then when I am winded and my heart is beating like a hammer at the top of a 20% hill, I have a good excuse to stop and catch my breath. "Hey David, I'm fine to keep going, but my front derailleur is f****g up! Hang on a minute!" The only time I ever paid for a "tuneup" I tweaked the shifting as soon as I rode the bike. Never again for me!

Don in Austin

graytotoro

So I had a phone convo with the mechanic and it seems that I might have cross-chained it by running 3(front) and 2-3-4 on the back. So I guess he could have a point. He did mention that he does go through quite a few chains/cassettes on his race bike, plus I don't think I've been the most gentlest rider on my bike.

Most importantly, he said that the shifting was a-ok, so it may not be the FD's problem and that it's at the point where it would be nice if I could change the chain, but I could just ride it into the ground. (past the ok-zone on his measuring thing)
Does this hold any water with you guys?

Thanks for all of your help.

Edit - it's at the shop right now. Again, they aren't charging me labor for this job. With this in mind, should I still go for it?

LarDasse74

Cross chaining is generally described as running in chainring 3 and cog 1, or chainring 1 and cog 9 (or whatever your highest gear is). Running it in cog 2, 3, or 4 is sometimes referred to as 'mild cross chaining' and might accelerate wear, but still not to wear out your chain in 200 miles! Something else must be going on...
...what your mechanic is suggesting is like saying that you bought a car and waited 3050 miles to change the oil...and the engine exploded because you were supposed to change the oil after 3000 miles. Maybe you didn't follow best practices but you did not ruin your bike by using slightly less than optimal gear combinations.

Have you measured the chain yet? You are asking if you should take them up on the offer of a new chain for only $20, but that might be a waste of $20 if the original chain is not actually worn! Measure 24 links an see how much it is longer than 12".

Also, if the chain is worn and you are experiencing chainsuck, a new chain will make it worse, not better..

Retro Grouch 

Yup. That's what I think too.

joejack951

Am I becoming a retro grouch? I commute on carbon fiber though! Oh, the hypocrisy.

cny-bikeman

No problem, I understand one cannot always do the right thing. The post was to give some general info to anyone who reads it, as I've seen quite a few posts from people who have said "I'm still 3 weeks away from my 60 day check."

rydabent

Chain worn out in 200 miles is totally BS. You would have to have ridden in a blowing sand storm to get that much wear. Your problem is undoubtably FD adjustments. Or a faulty shifter.

Retro Grouch 

Hopefully.

Raiden

You've mentioned they've checked the chain- but have they actually adjusted a derailer?

Take the bike in for its tune-up. Make sure to specify the problem (even if you've told them before- and don't buy the worn chain excuse- if the chain is toast in only 200 miles and the bike is <3 months old to you, its a warranty issue- suggest that they swap the chain and send the defective old one back to Specialized). Ask them to test-ride it after the tune-up.

When you get the bike back, tell them you're going to take it for a quick test ride, take it out, and try to make the problem happen again out on the road. If it still happens in exactly the same way, bring it back in and tell them (If it still happens in EXACTLY the same way, they didn't adjust it- or didn't adjust it enough). Don't let them re-book the bike- insist it be done then (at least by the end of the day)- after all, you notified them of the specific problem and asked them to test-ride the bike when you sent in in to be repaired, right? Don't be angry or confrontational; be patient and matter-of-fact. You'll be a thorn in some mechanic's side for a while, but this kind of service is why you bought your bike at a shop

Hopefully the problem will be nailed with the tune-up and the situation won't get so messy....

Edit: My guess is a bent derailer hanger or misadjusted high limit.

graytotoro

Thank you for all of your replies!

I will admit I am a bit of a pain in the ass - the bike was supposed "ready" Monday when the mechanic called with the news, but for various reasons that I won't get into, I was unable to get it until today. But I am calm over the phone - I don't belittle the mechanic or shout, so I don't think they'll throw darts into a picture of me yet!

If all goes well, I will go in almost as soon as the shop opens today, apologize for making them wait, and then go talk to the mechanic and have him explain everything. If he manages to show that it's stretched beyond a safe amount, I will nod, then ask the warranty question. If it's a no go, then I will still nod, and politely decline. Then say that I'll take it for a test ride; ride it around a bit, and then green light it if it's ok, tell them if no.

Thanks for all your help!