djSlvt

I had a rear dérailleur go on me today. Shimano 105, broke in half right above where it attaches to the frame, right above two screws. Why would it do that?





Chain broke too. Including the rear dérailleur cable. Plus scratched paint.



I was just about to leave my house, and was shifting from front 2nd to front 3rd when this happened. Sucks. I loved riding. I rode today instead around town. Beautiful. What usually took me 50 minutes on a car, took me only 35 on a bike. I was faster than cars on intersections, sometimes going in between and taking over. That was some fun.

Siu Blue Wind

Did you perhaps crosschain? What gear were you on in the back?

Oh by the way. We missed you in your other thread.

djSlvt

I only talk to people that interest me.


Rear was in the first. That is the shortest that there is - biggest. I don't think I cross chained, because I didn't touch the rear shifters at all.



I have this years shimano 105 in the rear. Do I have to replace it with the same year? Does last year or year before is different?

Any other brand that I could go with that is comparable to 105 but is a bit better in performance and price?


Man, this is sucks. I want to ride a bicycle. I rode for chores today and seen some HB8+'s catching a bus. We have a strip club there, so must be the strippers, or could be just a good looking hun catching a bus. So I had my pen and stuff and was going to ride there again, then go and hit the shops. I had 25+ miles in mind today, what the heck, bike is faster than a car with our traffic. This totally sucks.

Siu Blue Wind

Yesterday that almost happened to Jon (Pheard). He was in the smallest ring in back and was trying to go to the smallest ring in front.



With the flex and stress pressure, the chain snapped and got mangled as you see. No damage to the der but I'm sure there could have been if he didn't catch it as quickly as he did. He was going downhill and wasn't really putting pressure by mashing on it.

djSlvt

Well I'm not experienced and really strong, so this thing happened.

djSlvt

Can this chain be reused? I don't think it's missing any elements, but one of the elements where it broke is bent. It's a KMC Z9000 Super Narrow 9 Speed chain.


Perhaps this was a god's way saving my butt from something more serious on the road. Happened right near my house, like the best place it could have happened.

gear

You don't lay the bike on its' side do you? Some people do that when they get off or for transport and the derraillur or frame gets bent.

djSlvt

Nah, I brace my bike against the wall. It never even dropped. Chipped paint is one of my pet peeves, so I take care of things so they look nice. I rode the bike for about 10 miles today with no problems.

Siu Blue Wind

You sound like me. Mich said that one scratch = a new paint job to me.

What did you replace the der with? Another 105?

djSlvt

I'll probably replace it with another 105. I also have brocken chain, paint, and one spoke. I might look at service from a place I bought it from less than a week ago.


Any benefits from 10 speeds instead of 9? What's involved in swap?

Siu Blue Wind

I always thought that 10 speeds were better for climbing.

ericgu

Interestingly, I was on a group ride Friday night, and one of the riders was climbing on up a short hill on his new bike, when the derailleur broke off the bike.

It was also a Shimano 105.

I wasn't there, but from reports I don't think he was cross-chained.

v1k1ng1001

maybe it's a warranty issue?

djSlvt

Now that I look at it. It's not just one spoke that is bent. The whole rear wheel is crooked, goes from left to right and right to left when I spin it.

Is this related to a spoke? Will a new spoke or two fix this? Perhaps I need a brand new wheel?


What's a sure fix for this one, spokes or new wheels?

Cyclaholic

Isn't your bike brand new? as in only a couple of weeks old? that broken derailer should be covered by warranty along with all the subsequent damage.

The bent spoke ay have put enough extra pull on the rim to pull it out of true, which is that wobble you're seeing. The wheel can be brought back to straight, in fact spoked wheels sometimes need a little tuning like this, it's normal.

djSlvt

Thank you, I'm looking at fixing this asap.


Believe it or not, bike is like the best thing ever happened to me. I enjoy riding my bike better than driving my stang.

barba

My guess is that the chain broke, and that is what snapped the derailleur. Was the chain Shimano? Odds are the chain was not installed correctly. It is common with those little Shimano chain pins on narrow chains. If the bike is in fact new, I would be talking to a shop about a replacement. If you installed the chain, it may be on you.

djSlvt

Chain was KCV (or similar 3 letter name with K) 9 speed super narrow.


I plan to reuse this chain, after straightening out one of the lements. It looks ok now. Good idea or bad? Should I buy a new chain?


How to properly install a chain?

barba

The chain was probably KMC. I would just get a new chain. If any of the links are bent you risk the same outcome. If I were you, I would get a SRAM chain. The masterlink makes installation very easy. Just cut it to the same length as your current chain.

halfspeed

The benefit of going from nine to ten speeds is far less than the cost. Any Shimano rear derailleur of relatively recent vintage will work, regardless of "speeds". Get a cheap nine-speed SRAM chain. You probably don't need a new wheel, just new spokes and a truing. If it's warranty, of course, the bike shop will take care of all of this.

Rev.Chuck

Don't you have a Motobecane? Those ae usually mail order, there is an onliner dude always raving about how great they are. Where is he?

East Hill

If nothing else, I guess this proves that the OP isn't a shill... .

East Hill

vandeda

Nah man ... this totally sounds like the derailleur got caught in the spokes. My bet is derailleur stop was not adjusted properly, allowing it to get too close to the wheel. When he shifted the front derailleur and the chain bounced around, the rear derailleur bounced around too and nough to get caught in a spoke. This then twisted the derailleur around, broke it, bent some spokes and broke the chain.

Mountain biking a lot, I've seen my share of derailleurs into spokes, usually due to sticks. It can mess stuff up real fast! Bent derailleur hangers, busted derailleurs, bent/broken spokes, etc.

This failure has derailleur getting caught in a spoke written all over it.

What I would do is:
1) get a new chain! I had a chain fall off on my fixed gear and get wrapped around the cog. It looked OK, but I promptly popped a link a few miles later in the ride

2) get a new derailleur

3) make sure the stops on the derailleur are set right so it won't get caught in the wheel again!

4) check your derailleur hanger to make sure it's not bent!