Mountain Bike Reviews Forum banner
1 - 17 of 17 Posts

·
Registered
Joined
·
21 Posts
Discussion Starter · #1 ·
Hi,

I have a custom built bike that uses the Shimano BR-M765 brakes. They are stock 160mm centerlock rotors. I would like to upgrade the front to an 8" and the rear to a 7". If it becomes to pricey, I would at least like the front at 7".

My questions are as follows:

I have only been able to find Shimano making the CL rotors - they are pricey and not a quality as other brands. Does anyone else make CL rotors?

I have seen the 6bolt to CL adapters, are they any good? Which one would people recommend?

Thanks.

My bike info can be found here: http://forums.mtbr.com/showpost.php?p=4074774&postcount=1

Tires are different, and I now have Eggbeater SLs.

Other than that it is the same
 

·
Registered
Joined
·
1,188 Posts
Go to XTR rotors, it's worth it. When I installed an XTR 20mm hub, I went from Hone 8 inch to XTR 8 inch rotors.
although I asked the LBS to install 7" in the rear they intalled 8" because that is the way the bike came set up from the factory. I thought it was overkill until I rode the bike a couple of times. I softend the rear brakes at the lever, and I still have enough power to stop the bike using rear braking only. The caliper/pad are still hone, but with the XTR rotors it brakes much better. I believe that the rotors are much thicker and stiffer with the alloy arms.

If you still want to go to 6 bolt adapter, the shop told me they work good.
 

·
err, 27.5+
Joined
·
4,928 Posts
Shimano is the only readily available CL rotor. Magura and Avid are working on versions though. The adapters work fine, but I would recommend the Shimano CL rotors over them especially since you are using shimano brakes.
 

·
err, 27.5+
Joined
·
4,928 Posts

·
Registered
Joined
·
21 Posts
Discussion Starter · #6 ·
I found Shimano adapters however, on Jenson they are ~$46 for the 180 and $64 for the 203mm. That seems WAY too much.
 

·
Fo' Bidniz in da haus
Joined
·
17,282 Posts
how heavy are you?

how gnarcore of a rider are you?

its may very well be that all you need to better the situation is a 180mm up front, and keep the 160mm out back. Shimano brakes kick ass so unless you are a fatass and/or ride the STEEP gnar with long downs, just save some money, headache, and time and just replace the front
 

·
Registered
Joined
·
21 Posts
Discussion Starter · #8 ·
I am 210 and by no means a fat ass. I think I will try the 180/160 combo, I can always buy the 203 in the future.


Thanks.
 

·
Registered
Joined
·
21 Posts
Discussion Starter · #9 ·
I do not do hard-hardcore stuff, however there are some steeps that require a lot of brake. I am in CO I mainly ride Evergreen trails and Lair of the Bear.
 

·
err, 27.5+
Joined
·
4,928 Posts
Wow, uncharacteristically wise words from FoShizzle :p

I suppose weight and riding style should have entered the conversation before Fo, but I guess he is entitled to be on the ball from time to time.

For reference I am 240lb and have never "needed" more than a 7in rotor. I cook 6in rotors on steep and long descents, but typically find 8in rotors a bit grabby for general purpose use. The exception, and there is always an exception, was my 29er. I used 8in rotors and a resin pad to get great stopping power and modulation. On a 26in wheel I typically don't like an 8in rotor, but it was right at home on my 29er.
 

·
Registered
Joined
·
21 Posts
Discussion Starter · #11 ·
Thank you all for the input. I think I am going to go 180 front and stay 160 rear.


Once again, Thank you,

-Josh
 

·
Northeastern Rider
Joined
·
762 Posts
good choice. I am 240. I find w/ my xt calipers that I dont need more than a 180 up front for most any riding(minus big downhill). The 160 is easily enough brake on the rear.

I think you've made a good choice.
 

·
Registered
Joined
·
21 Posts
Discussion Starter · #13 · (Edited)
Now that I have the rotor size squared away, I am onto the caliper adapter, which is way more confusing than I thought.

From reading the tech doc on Shimano's website, they list the adapter for a 160 and a 203, no 180. However when I changed the model numbers from

sm-ma-f203p/p to sm-ma-f180p/p
sm-ma-f203p/s to sm-ma-f180p/s

I got results. Now, I am thinking I want the p/p, being the post mount, and not the p/s being the A-Standard mount. However, let's be honest I do not really have a clue.

My front fork is a 2008 Fox Vanilla 32 RLC with quick release. The docs are no longer on Fox's website so I am unsure of which mount I need. I am going to guess that as the 2009 is a post mount, my 08 is going to be. Any reason to think otherwise?
 

·
err, 27.5+
Joined
·
4,928 Posts
Simplicity = a call to Larry or Chad

One stop shopping. Tell them what you have and what you want. They will do the rest and usually do pretty darn good on the price FWIW :thumbsup:
 

·
Registered
Joined
·
21 Posts
Discussion Starter · #17 ·
AL29er said:
Simplicity = a call to Larry or Chad

One stop shopping. Tell them what you have and what you want. They will do the rest and usually do pretty darn good on the price FWIW :thumbsup:
Thank you. I will call in the morning.
 
1 - 17 of 17 Posts
Top