For decades, mountain bike technology has worked according to the modular principle. As long as shifters and rear derailleur originated from one manufacturer the remaining add-on parts could be combined at choice. In the era of nine- and ten-speed derailleurs, you could safely cross a Sram rear derailleur with a cassette and chain from Shimano. But with the increasingly specific design of MTB components, this principle is beginning to crumble. And this really a lot. The universal HG freehub standard is more and more replaced by the manufacturer own XD (Sram) and Micro Spline variants (Shimano). Those who have the latest Sram twelve-speed drivetrain can no longer mount a Shimano cassette without also changing the rear wheel or at least the freehub.
Nevertheless, the question remains: Can a twelve-speed drivetrain of Sram be used with a twelve-speed cassette of Shimano? For example, if you have a second wheelset at home that is already equipped with a cassette. And frequent riders also have another completely different motivation when combining spare parts: Shimano cassettes are usually slightly cheaper than the comparable product from Sram. Example: One of the leading online shops offers a Sram-GX-Eagle cassette at 160 Euros. In the same shop, a Shimano XT-twelve-speed cassette costs 145 Euros. But does it really work?
We have looked at all conceivable combinations in the areas of gears and brakes in practice and have come to the conclusion: Especially with current twelve-speed derailleurs, hardly any combination of Sram and Shimano parts is possible. The modular principle is thus history. What is still possible, fortunately: It is possible to combine the different groups of one manufacturer.
Read the German article online.
Author: Ludwig Döhl
Dirk Zedler, bicycle expert
BIKE: The brake is a safety-relevant component. Should one compromise here with individual components of third-party suppliers?
DIRK ZEDLER: Especially with the brake, this topic should be treated with caution. Because if you are involved in an accident due to brake failure and third-party parts are installed in the brake system, it is in case of doubt the person who mounted the component mix that is liable. The mechanic is then obliged to prove that the brake pad or brake disc of a third-party supplier does not affect the performance of the brake in a negative way. Such proof is difficult to provide.
In case of doubt, it is the bike shop mounting cheaper aftermarket brake discs or pads that is liable?
I assume that reputable manufacturers of aftermarket brake pads or brake discs carry out tests with the most common brake systems before selling spare parts in order to ensure and document perfect functioning. As a big customer, you might even be able to have such documents shown to you. If you don’t want to rely on this, you should only mount original components in the area of the brake.
So much for the theory. What about practice? Are there many accidents that are to be attributed to an improperly mounted brake?
In practice, it is quite common that brake pads of third-party suppliers are mounted. However, I am not aware of any accidents occurring as a result thereof leading to a liability problem. If the brake fails, it is usually due to external influences. If, for example, oil from the suspension fork gets on the disc. Nevertheless, it is advisable to use products from reputable manufacturers. No-name brake discs or pads from unknown sources always bear a risk.
The interview was held by: Ludwig Döhl