Magura Marta SL adapter help!
I just bought a set of Marta SL brakes off of eBay. I didn't realize that the caliper was designed for IS mounts. Have never seen this before. Anyhow, I have a Niner post mount fork and need to find an adapter to convert my IS caliper to PM. I have found some discussions about doing this on the web but in all honesty I think I may have gotten myself even more confused! I think it can be done but I'll have to go from a 160mm rotor to a 180mm but that won't be a problem. Can anyone tell me if I'm thinking correctly and if this is the adapter that I need? Thanks!
That adapter will work but IS calipers come in different sizes.
IS caliper sizes: 160mm front/140mm rear, 180mm front/160mm rear and 200mm front/180mm rear
In this photo you can see some Marta SL's, the caliper on top is the 160mm front / 140mm rear and the caliper on the bottom is the 180mm front / 160mm rear.
The adapter you linked will work with a 180mm rotor only if you have a 160mm front caliper, if you have a 180mm front caliper then you can only use a 200mm rotor with that adapter.
If you have a 160mm caliper and want to use a 160mm rotor it might be possible with the following 160mm KCNC adapter, this 160mm adapter will also allow you to use a 180mm rotor with a front 180mm caliper.
KCNC Adapter: http://clee-cycles.co.uk/esite/P1043/product
This adapter doesn't work with all IS calipers because their shapes.
This adapter doesn't work with all PM forks as the post mounts can vary in size and shape.
I'm fairly sure that the KCNC adapter will work with a Marta SL as it's a smallish caliper.
Here's a couple of photos of this adapter on different forks:
Photo of a 160mm KCNC adapter + 180mm Caliper + 180mm Rotor
Photo of a 160mm KCNC adapter + 160mm Caliper + 160mm Rotor
The problem you would probably run into with this 160mm adapter will be your fork, it won't work on forks with a very short bottom post mount like this or on forks with a thick/wide bottom post mount like this or if both post mounts are short - forks with larger diameter lowers will have shorter post mounts then forks that have smaller diameter lowers .
There is a bit of flex in this adapter which allows this adapter to be attached to a fork when it looks as if it won't work. Photo 1 and Photo 2. The little bit of flex in the attachment wouldn't be a problem once the adapter is bolted onto the post mounts, the bolts that attach it would keep everything firm.
Last edited by cobba; 01-09-2013 at 11:31 PM.
Nice work cobba.
Flat Ark, Use a Magura adapter as first choice if possible. Should be zero flex and is designed by the factory.
If your front caliper has 2 short mounting legs on the caliper, it's a front caliper designed for a 160 mm rotor with/out the adapter you request. The adapter will increase the rotor size needed by 20 mm.
If the caliper has 1 short and 1 long mounting leg, it's designed as a rear caliper for a 160mm rotor mounted directly to the IS frame mount.
Great info guys and thanks a lot! That really helps! Looking at the photo, the front caliper looks to have 2 short mounting legs and the rear appears to have 1 short and one longer leg making them both 160mm calipers. However since the front will require a post mount adapter I will need to run a 180mm rotor (which I just happened to have one).👍