Bikes-N-Drums

I've always loved Cannondale. It was my first of many of my adult bikes. Had a mountain, road and hybrid Cannondale. Always reliable, totally solid: I never really had any problems with them.

For about a decade I had quit riding. One reason was the inexorable fact that I couldn't as I was a touring musician. Then I got a severe back injury. It took me out of the game for, what I thought, would be forever.

I went out and bought a bike a month ago and found it gave me very little back trouble. I'm back in the game! I bought a Cannondale! This time a nice, new Quick 4. Man, what a great ride!

So it's breaking in, I'm riding it, and the gears are a little "funny" (which I expect for a while in break-in). It clackles and jumps a cog, all that fun stuff. Then after about 25 miles it starts throwing the chain off the upper sprocket on the rear cassette. Hey, that's no good! At 75 miles it was happening more often and starting on the front cassette too.

At just 100 miles a catastrophic drive train failure. The chain jumped the bottom rear sprocket and bent the Deore derailleur outwards like an aircraft wing. This is at least the third Deore I've broken in but never had a completely craptastic flunkathon in the first 100 miles of any bike. I've never had this happen after 1000s of miles. I took it back. I told them I didn't want the damned thing.

Did I get a lemon Derailleur? Has Shimano turned to Shine-ola since I've been gone?

DrIsotope

Nothing at all to do with Cannondale or Shimano, and everything to do with an improperly adjusted rear derailleur.

GuessWhoCycling

Yeah, bad adjustment. Of course if it was clackled and jumped a cog at 25 miles as you described, I would have adjusted it knowing something bad could only happen.

I'd be surprised they take it back if you told them that.

IslandTimePE

Sounds like you could have used an adjustment of your derailleurs. During the breaking in period, cable stretch slightly, etc. so it isn't uncommon to have to tweak/adjust the derailleurs/shifters to maintain optimum shifting.

Is it the derailleur or the derailleur hanger that bent? Typically the hanger bends - that si a big part of why it exists. If that is the case, all you need is a new hanger and the derailleurs readjusted and you should be good to go. But if you really wrapped it around, the derailleur itself may also be bent now.

I doubt there is any need to return the entire bike. Cannondale are a fine brand and Shimano products are as good or better than ever.....but they still need a little TLC to keep things working well.

TrojanHorse

You were given all the signs of impending doom from the get go and ignored them. Work with the shop to get it repaired and go enjoy it. Honestly, bike transmissions should be nearly dead silent - if they're not, something probably needs adjusting.

Good luck.

Maelochs

For future reference---if you buy a bike at a shop and it makes funny noises, feels odd, doesn't seem to be quite right---take it right in for a check-up.

That is one of the main benefits to paying bike-shop prices---they do tune-ups (and they had best be free for life, so long as you don't abuse your gear.)

But certainly .... if it isn't super-smooth and quiet the day you get it, don't even take it home, and if in the next few days/weeks (depending on how much you ride) it makes noise (which it almost certainly will) bring it in.

Likely a mechanic could have fixed that with two turns on the barrel adjuster at 25 miles.

Anyway ... I rode with a guy with a Quick two Sundays ago---he has two (one up north, one down south because his work is seasonal) so he pretty obviously loves them.

Get it working and enjoy it, I'd say.

shelbyfv

Operator error. If you've broken three Deore derailleurs, that clarifies the situation. Sure it should have been adjusted properly but continuing to ride it is what caused it to break. If you like the bike, just pay to have it repaired and learn how to operate it.

GrainBrain

Lol break-in period?

I had the same symptoms and it turned out to be a stiff link, defective chain. Did 12 miles, thought this isn't right, and immediately headed to the bike shop for inspection.

How do you shuck three deore rd's? fyi a bike chain should always be smooth running and quiet, from Tourney to Dura Ace right from the start.

GuessWhoCycling

"Breaking" and "breaking in" a deore derailleur are different things, No?

355Mono

Must be a drummer.

GuessWhoCycling

Not necessarily a tech error.

New cables take time to break in. Could need one adjustment, could need two or three. Each cable can be different. I've had some stay dialed in from the very start.

Bikes-N-Drums

That was slick, my friend

Bikes-N-Drums

No. I did not break them. I "broke them in". Let me rephrase, 'cuz I hosed it.

Previously, I've bought three new bikes with Deore RDs and rode them through the cable-stretching ("break-in") period without issue.

hillyman

It's a 10 speed and you turned it up to number 11?

SEAJAYBIKE

I don't think cable stretch is going to put a der into the wheel. More than likely a link, bent hanger or bent der or limit screw issue.

355Mono

Hello! Anyhow, good guess on my part, being too stupid to notice your NAME!!! BTW, we have an older Quick 4, and it needed adjusting, but we took it in, and didn't break it...

355Mono

Us guitar players are so self-centered, we don't pay attention to anything but US! sheepish lol...

DrIsotope

As an accredited internet mechanic, I can say with 86% certainty, limit screw issue. Dropping the chain to the outside is either limit screw, bent RD, or bent hanger. The latter two will usually also mess up shifting at one end of the cassette or the other. But unless the bike was dumped, or the hanger was never checked when the bike was built, limit screw.

hillyman

Yea just saw name myself. I remember when you was here before. What happened to avatar?

Bikes-N-Drums

What was my avatar?

prathmann

If the tech applied enough tension to the cable to ensure that everything along the length was fully seated then it should stay dialed in for a long time.

But a little loss in cable tension shouldn't result in the OP's result. I agree with others that it sounds like a limit screw issue in addition to poor cable adjustment.

Lazyass

Aside from the fact I would have checked the tune before riding the first time, the moment it jumped a cog I would have pulled to the side of the road and properly adjusted it, or turned around went back home to put it on the stand.

When I bought my last brand new bike off the sales floor at Performance Bike, I took it home and went over everything before I rode it. I discovered the derailleur hanger was bent, probably from shipping. I had to straighten it and retune it, then I discovered the FD wasn't tuned properly and the trim adjustments didn't work. Never trust anyone but yourself.

jefnvk

+1 to all the improperly adjusted rear derailleur suggestions.

Odd. We have an entire thread on people who aren't experienced reaping benefits going to an LBS and paying more so they know they are getting something good when they walk out the door, now we are suggesting that bikes that come from the LBS need to go over when you get it home to make sure nothing is screwed up?

hillyman

Seems like a cartoon drum kit. Maybe tied in bikes. But I change avatars all the time so Im one to ask wheres someone elses

Lazyass

I'm not sure why anyone would not go over their bike before they ride it. It only takes a minute to double check the brakes, check bolts and shift through the gears. And then if you are totally clueless on how to fix something and don't want to learn then take it to the shop so someone else can do your work for you. It's not a major life event. If the OP had done that then he wouldn't be in the situation he's in.