Need help fixing rear derailleur

Madhu · 06-26-2014, 03:17 PM

I have trek bike and use it occasionally. My rear derailleur is broken and part of it hanging. I tried it put it in but it doesn't hold on anymore.

Please suggest if it can be easily fixed or need to take to a bike repair shop. Added some pictures

Painkiller · 06-26-2014, 09:33 PM

replace it
http://www.ebay.com/itm/Shimano-RD-M360-Acera-8-Speed-Rear-Bicycle-Derailleur-Black-New-Great-Replace-/221447293216?pt=US_Derailleurs_Rear&hash=item338f498920

Madhu · 06-26-2014, 10:38 PM

(06-26-2014, 09:33 PM)painkiller Wrote: replace it
http://www.ebay.com/itm/Shimano-RD-M360-Acera-8-Speed-Rear-Bicycle-Derailleur-Black-New-Great-Replace-/221447293216?pt=US_Derailleurs_Rear&hash=item338f498920

thanks for the reply.
So this model is the same one that I have or do I need to check anywhere for the exact make/model?

Painkiller · 06-26-2014, 11:03 PM

rd-m360 is the one in my link. it will work on 7,8 speed
you can look on the back plate to see what yours is. It will start with RD-
there are others that will work too. just happened to see this one on ebay.
It is a decent price, you could even go alivio if you want to spend more money

DaveM · 06-27-2014, 05:35 AM

Could just be a trick of the photo, but your derailleur hanger looks bent in to me (part of the frame that the derailleur screws in to.) If that little threaded tab on the frame isn't perfectly vertical you may want to check it or have it looked at. It will make it very hard to get your gears adjusted if it is bent.

nfmisso · 06-27-2014, 10:44 AM

(06-27-2014, 05:35 AM)DaveM Wrote: .... very hard to get your gears adjusted if it is bent.

very hard = IMPOSSIBLE.

Madhu · 06-27-2014, 11:40 AM

(06-27-2014, 10:44 AM)nfmisso Wrote:
(06-27-2014, 05:35 AM)DaveM Wrote: .... very hard to get your gears adjusted if it is bent.

very hard = IMPOSSIBLE.

from these pictures can you tell. if not, i will just take it to a bike shop and hopefully not get charged a bike cost Smile

nfmisso · 06-27-2014, 12:22 PM

can't tell from the pictures - we are talking hundredths of a mm off at the hanger. Hanger alignment tools register off the rim, which in your case is 280mm away from the hanger, and is easy to adjust to within 1mm of the rim. 3mm off at the rim - 0.01mm at the hanger - results in very rough running.

Madhu · 06-27-2014, 12:48 PM

(06-27-2014, 12:22 PM)nfmisso Wrote: can't tell from the pictures - we are talking hundredths of a mm off at the hanger. Hanger alignment tools register off the rim, which in your case is 280mm away from the hanger, and is easy to adjust to within 1mm of the rim. 3mm off at the rim - 0.01mm at the hanger - results in very rough running.

ok. I will give my bike to local repair shop, looks like its not too expensive to get it done there. will post feedback once repair is done with some pictures.

Madhu · 07-02-2014, 02:51 PM

(06-27-2014, 12:48 PM)Madhu Wrote:
(06-27-2014, 12:22 PM)nfmisso Wrote: can't tell from the pictures - we are talking hundredths of a mm off at the hanger. Hanger alignment tools register off the rim, which in your case is 280mm away from the hanger, and is easy to adjust to within 1mm of the rim. 3mm off at the rim - 0.01mm at the hanger - results in very rough running.
ok. I will give my bike to local repair shop, looks like its not too expensive to get it done there. will post feedback once repair is done with some pictures.

Got it replaced and a complete tune up done that involved re-adjusting the wheel and spikes and other maintenance for 80 bucks + parts for rear derailleur. thank you guys for taking time to help me out.