Sram Schaltwerk ESP X4 (8/9-Gang | Langer Käfig | 1:1)

Works as a replacement of SRAM X3 1:1, albeit with X4 I was able to get only 6 out of 7 rear gears. The huge advantage of SRAM X4 is that it can be installed on a bike without breaking the chain!!! You can remove the two little guide wheels on X4, install it, then put back the guide wheels back. I give it 4.5 stars for non-perfect fit as a replacement of X3, upgrading to 5 stars because of a reasonable price.

This SRAM X-4 rear derailleur replaced my damaged 1991 SunTour derailleur. 4 months ago I fixed the worn Sun Tour upper pulley - jockey wheel with a hard to find pulley and it work with some modifications. (Note SunTour been out of business decades, and forget about NOS -new old stock .) It was still very difficult to down shift the rear 7 cog gear set. And I essentially had only 4-5 gears that the SunTour would drive. So after damaging the Sun Tour and purchased the SRAM X-4 last week. I received it yesterday and installed it. First impression are- well made metal construction and heavier than the Sun Tour. I had to loosen the both jockey wheels in order to get the chain routed through. I adjusted the H, L and B screws to smoothly shift through all 7 cog set 12-28. I made the first ride today, what a difference. So much easier to up & down shift and much more precise. No more death grip to shift down to lower gear (bigger gear) The only issue was sometimes it would not stay in specific gear and shift into a higher cog-gear. Maybe do some more fine tuning of the H,L, B and cable tension. But I may just leave alone, if its not really broken, don't fix it. Usually I make things worse by screwing around too much trying to make it perfect. . I also using the Sram Grip shifter. But overall really please with the Sram X-4. Gave my 1991 Cannondale SM-1000 new life.

This was a replacement for the identical derailleur that came on my 2011 Trek Ticket Exchange. Funny how smacking the derailleur on the side of an aluminum bleacher bench can mess it up... ;) I'll go the old 'pros & cons' route here, cons first:Cons:* Really only one: all of the adjustment screws (high/low limit & b-adjust) have a small sharp "tip" on them for some reason. In the case of the b-adjust, the tip actually eats/chews into the body of the derailleur, right on the edge of a lip, and eventually with some thrashing & such the derailleur body can kind of bounce around between two points (on the tip and off), totally ruining your shifting short term and long term breaking up the metal edge of the derailleur body and ruining the entire unit. I strongly suggest when you get this new, remove the b-adjust screw & use a hacksaw/file/etc to just remove that little sharp tip from the screw to avoid this. This allows the screw to sit squarely on the metal body of the unit.Other than the above, I've been happy with this derailleur.Pros:* Performance: it shifts well, no complaints here. It's pretty crisp, no sloppiness, and no slippage so far* Price! I'm loving it because I frequently bang things up, since I am mostly freestyling on/around concrete which is not forgiving to derailleurs (or anything else). MSRP is $26 bucks.

I received this product more than a month before I installed it. I found that when I was going to install the derailler, it was missing the B-bolt. I could not return the product because It was beyond the return grace period. I contacted SRAM tech support, which is excellent BTW. They suggested that I contact the seller to see if they could help me. I sent a picture of the derailler with the missing B-bolt, and they sent me a replacement! This vendor is top notch. They responded quickly and resolved my issue by sending me a replacement derailler, despite my not being able to return the product through Amazon. I have a few SRAM products and highly recommend them. I also highly recommend this seller, as they take good care of their customers.

Great derailleur! I bought a used Schwinn hightimber from my local shop and had awful shifting for weeks before I decided to swap it out.Combined with an sram index shifter (a 1:1 ratio shifter is required for this derailleur which I didn't know at first) I'm more than happy on my rides to work now!I have to take a small hill to get there and I couldn't hold a gear let alone shift while pedaling hard but now it's so crisp and fast I don't even think I just shift. And for the money (about $60 all together for the swap) it's a great deal considering it made my used bike feel brand new again!Can't say how long it will hold up with abuse but I don't do much trail riding anyway. Will be getting a gaurd for it just to be safe

Product arrived on time and in manufacture’s packaging but the box was ripped and appeared to have been tampered with. The bolt and hanger used to attach the derailleur to the bike was missing.

I ride mostly cross country. I wanted a cheap upgrade from my Shimano Altus derailleur as I needed to tune it after every ride and I couldn't justify upgrading to any Deore components.I've had it for a couple of weeks now (over 120 miles) and can say this an excellent derailleur. It easy to adjust and tune. It shifts crisply and cleanly even under some tough conditions. This has definitely won me over to Sram products.I highly recommend this for its excellent bang for the buck. Just keep in mind you will need Sram shifters to use this.

I replaced a 22 year old 7.0 rear derailleur with this. It appears to be built well and works well.Don't try to use this with Shimano shifters though since the ratio is different. Works fine with my 7.0 shifters.