On 2017-10-05 15:41, jbeattie wrote:
On Thursday, October 5, 2017 at 12:39:02 PM UTC-7, Joerg wrote:
On 2017-10-05 12:34, Joerg wrote:
Some rotors are sold for "resin pads only", others do not list
restrictions. What is the difference in materials?
I am using ceramic based pads not normally sold at the LBS,
supposedly similar to what motorcycles have. Because they give me
best results.
Other questions while at it:
My rotors are formally 7" and 6". Can I use 180mm and 160mm
instead? The 7" one on my MTB actually measures about 185mm. I'd
hate to have to grind down the spacer but might have to because
7" is more rare.
Does anyone know what the raw rotors foer custom-laser deals are
called? Couldn't find any on EBay. Ideally I'd want rotors that
are solid like on motor vehicles, for better heat tolerance.
Weight doesn't matter.
Add-on: I am also looking for at least 2.2mm thickness like the
originals from Promax. The newer ones from Promax only have 2mm and
also a weird wavy design:
http://i.ebayimg.com/images/g/qjAAAO...rj/s-l1600.jpg
-- Regards, Joerg
http://www.analogconsultants.com/
Hayes makes the 5-7" rotors.
https://www.universalcycles.com/shop...ls.php?id=5018
The data on those is a bit unreliable. For example, here the same P/N
98-17551 rotor is listed as 160mm which isn't 6":
https://www.worldwidecyclery.com/col...-with-hardware
I believe Hayes rotors are also only 1.9mm thick and I'd be through that
in a jiffy.
It was similar when I bought a BB for my road bike. Most US dealers
listed it as JIS taper which is what I needed and most UK dealers listed
the same P/N as non-JIS. Shimano had no "Contact us" on their home page.
Luckily it ended up being JIS.
You could always go with a bigger metric size and add spacers rather
than going smaller and grinding down your current bracket. You would
have to get longer bolts probably. This would also accommodate your
gnarly riding style and need for maximum braking power. Go big or go
home!
Indeed. I am thinking about upping the front to 203mm which equates to a
true 8". With 7" you always have the discrepancy and a standard 180mm
rotor is 5mm too small so I'd have no choice but to grind off.
My style isn't so gnarly but we have long steep descents here. A friend
who rode ahead of me lost his front brake before the last sharp turn
once. That was a real white-knuckle situation. It was weird, he had 8"
versus my 7" and weighs less, same route and speed.
I use sintered metalic pads because they last a long time and work
well in wet conditions. I am not familiar with the ceramic/metal pads
except that I have seen them on the rack.
The ceramic-based ones last much longer for me. But who knows, maybe the
sintered ones I used before didn't like wet rides too much. The only
downside is a sandpaper sound when they are applied for a long descent
and become hot. Goes away once cooled off.
All one piece rotors I know of are SS, although you can buy CF
rotors.
There must be different steel in Shimano SM-RT56 versus SM-RT66 rotors
because they do not allow the RT56 to be operated with anything other
than resin pads.
... Magura (and I think Avid) makes thick rotors (2mm) that are
supposed to be good at shedding heat, but I don't know of anyone who
makes them thicker than that. You'll have to do some detective work.
It'll be tough because the thickness is almost never listed. There used
to be custom shops where you could have a rotor with a laser-cut
"Beattie Racing" made. One of them had 3mm thick versions and I could
ask them for raw rotors (full discs, no gaps, like on many motor
vehicles). However, seems they are gone.
I wish the original thick Promax rotors were still available. They are
really good but the micrometer shows them down to 1.75mm in front and
1.65mm in back. So they need to be replaced soon.
--
Regards, Joerg
http://www.analogconsultants.com/