Which Parts to Replace

How should I determine which parts need to be replaced?

Madrone offers several replacement parts, but we do not offer replacements for every part.

You will need to inspect the derailleur to determine which parts need to be replaced, and which ones are OK.

Derailleurs that have been well cared for, but are worn out and not shifting well anymore are good candidates for a rebuild. If the derailleur has been abused, damaged, and impacted, there is a risk that a non-replaceable SRAM part could be bent or damaged. The inspections below will help you assess the derailleur. If a non-replaceable SRAM part is damaged, the derailleur is probably not worth rebuilding.

Please follow the inspections below:

1. Inspect the mounting bracket. This is the most difficult part to inspect. You can use the visual guides below to assess your mount. Focus on the 3 areas shown below to assess how much impact force the mount has been subjected to. If they are bent, do not rebuild the derailleur. 

2. Check the clutch. Make sure the clutch still applies friction by rotating the cage back and forth. You should be able to feel friction if you rotate it forward, and little to no friction in the opposite direction. Note: The spring will also apply force when rotating it forward, but you should also feel friction. If your SRAM clutch is worn out, we do not have a way to service or adjust it.

Clutch Housing: The plastic SRAM clutch housing should not be deformed or cracked. This is the structural part containing the clutch and torsion spring for the cage. 

Cosmetic Clutch Cover: On AXS derailleurs, there is also a cosmetic cover on the clutch housing with the SRAM graphics on it. This part has no function, and is not technically required. You may be able to find sources online for them too. More info on the cosmetic plastic covers is here.

3. Check the battery contacts. These are 2 small spring loaded pins located on the servo. They should make contact with the battery. Here is a guide for checking and recovering them, and it also has tips on preventative care. Madrone does not offer replacement services for these any more, but we do have a detailed DIY repair guide here.

4. Check the battery latch. If your plastic SRAM battery latch is broken or worn out, unfortunately we do not have a solution for this. The battery latch should snap over the battery, holding it securely against the battery contacts on the servo.

5. Check the servo function. Install the battery and make sure the servo functions correctly.

• Stripped gears. If the derailleur has been forced to move, it can strip the servo gears or cause them to slip and end up incorrectly indexed. This is why you should never force the servo into another gear by hand.
• Buggy firmware behavior, or damaged electronics. If you think you have an electronics issue, you may want to attempt to get it covered by warranty, but the outcome may be determined case by case.
• Bent servo lever arm. These can get bent in large impacts.

6. Check the remaining parts. Madrone offers the parts listed in green, and they can be selected here. Make sure to check the compatibility on each product page.

SRAM AXS Derailleurs:

When is a derailleur not worth rebuilding?

If you perform the inspections listed above on the un-replaceable SRAM parts, and you find something that is damaged, bent, or no longer working, it is not worth rebuilding.

If you find damage to replaceable parts, there is a solution for those. 

 

What are the most commonly replaced components?

Very Common / Most Critical	Links and Super Shims 2 common sources of poor shifting are play and deformation in the links and mounting bolt of the derailleur. These are common due to the high stresses in those areas. The derailleur assembly is like complex lever arm where the highest stresses occur nearest to the attachment point. We find that most used or semi-functional (but not destroyed) derailleurs are brought back to full shifting performance with the Missing Links and Super Shims. These products tighten up the pivots and result in a stiff, well aligned, smooth working mechanism.
Medium Importance	Cages A bent cage can also contribute to shifting issues, even though the links are more important to address. If your cage is even slightly bent, it will need to be replaced.  Pulleys Worn pulley bearings and teeth can be a small contributor to shifting issues. For the upper pulley, shift performance relies upon the bearing tolerances to shift well, and they can wear out quickly when exposed to grit and water. New pulleys can be thought of as putting the “finishing touches” on shift performance to get it back to 100%.
Less Common	Pivot Pins Unless the pivot pins of the links are clearly bent, they rarely need to be replaced. However, if you do need them, the Madrone pins are an excellent replacement. Plus, the Madrone AXS pins give the derailleur improved looks!