Bicycle Mechanics - trying to source sram x4 rear derailleur

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gtpro
09-14-10, 03:46 PM
Hi

I need to replace my sram x4 rear derailleur 7/8 sp (medium cage), however I am finding it very dificult to locate this particular item. I've seen a couple of sites that sell it but they all "long cage" not "medium cage". Anybody know of any retail online stores or suppliers based in (order of preference) 1. uk 2. europe and 3. usa, who sell this particular make and model?

I will also be interested to hear about other deraileurs that match the above specification.

Thanks


reptilezs
09-14-10, 05:43 PM
a long cage can be substituted

Mondoman
09-14-10, 08:02 PM
A medium cage X5 can also be substituted. Basically, it looks like it's just a heavier-duty X4 (cages made of steel instead of plastic).
For example: http://www.petracycles.co.uk/sram-rear-derailleur-89spd-medium-cage-silver-p-70136.html

If you do put in a long-cage model, you'll have to install a new (longer) chain as well.


vredstein
09-14-10, 10:12 PM
Hi

I need to replace my sram x4 rear derailleur 7/8 sp (medium cage), however I am finding it very dificult to locate this particular item. I've seen a couple of sites that sell it but they all "long cage" not "medium cage". Anybody know of any retail online stores or suppliers based in (order of preference) 1. uk 2. europe and 3. usa, who sell this particular make and model?

I will also be interested to hear about other deraileurs that match the above specification.

Thanks

Upgrade to the X5 is well worth it. I build bikes with X4 all day and while they can be adequate, the small price increase for X5 will make a difference.

Chris_W
09-14-10, 11:32 PM
If you do put in a long-cage model, you'll have to install a new (longer) chain as well.

Why would you need a longer chain? The big-big combination still has the same number of teeth, cage length does not come into chain length calculations.

I agree with the above, an X5 will be much easier to get after-market and will be a slight upgrade, so look for one of those.

gtpro
09-15-10, 12:12 AM
Why would you need a longer chain? The big-big combination still has the same number of teeth, cage length does not come into chain length calculations.

I agree with the above, an X5 will be much easier to get after-market and will be a slight upgrade, so look for one of those.#

I will prefer the original spec that came with the bike which was a medium cage derailleur.

If I was to go with X5 will I have to upgrade anything else e.g. chain, shifters etc.?

Someone mentioned X5 will be better, can I ask in what way?

Finally is the X5 available for 7/8 speed (medium cage) ?

Thanks

JiveTurkey
09-15-10, 12:38 AM
The X4 and X5 are perfectly compatible with each other; nothing else will need to be changed. The rear derailleur does not care how many gears you have. The link is post #3 is for a medium cage X5. If you can only find a long cage version, there will be no downside other than it being slightly heavier.

JonathanGennick
09-15-10, 06:14 AM
I will prefer the original spec that came with the bike which was a medium cage derailleur.

Don't obsess about things like that. Life is too short. You got an X4 on that bike because the manufacturer specified it to meet a price point. That's all. If an X5 is easier to get, then I'd grab an X5 and be done w/it. Otherwise, you can go nuts sometimes trying to source a specific part that may not even be made anymore.

I did take a look at the specs on sram.com. The inner cage on the X4 is made from "composite" material. In other words, it's plastic. The inner cage on the X5 is steel. Me, I'd go w/steel.

The X5 can also handle a nine-speed cassette. That probably does not matter to you. But it matters to those of us who are frequently tearing down one frame to build up another.

BTW, are you familiar w/derailleur adjustment? If not, it may be easier for you to just buy a derailleur at a shop and pay them to install it.