On 2017-10-21 17:19, Frank Krygowski wrote:
On 10/21/2017 4:07 PM, wrote:
On Saturday, October 21, 2017 at 7:12:03 AM UTC-7, Joerg wrote:
When researching upgrades to larger rotors I read that there may be
limits for frames and forks. Why?

Explanations were usually scant and contradictory, with some saying it
doesn't matter and some saying it does. After all, when increasing the
rotor diameter by a couple of inches the brake force on the caliper goes
down by about 30% and then due to it being positioned farther out this
should cantilever back into the same +30% into the frame or fork bosses
as before. The maximum deceleration achievable on each wheel remains the
same, until it is very close to locking up. So it should be a wash,
shouldn't it?

Now THAT is something that Frank should be able to answer. I don't
believe that leverage forces are linear are they?

Give me a photo and I'll see what I can do.


This is what I am planning to do:

https://ep1.pinkbike.org/p4pb12868017/p4pb12868017.jpg

The fork has this kind on there right now because the rotor is 180mm (or
in my case 7") and the fork is native 160mm:

https://ep1.pinkbike.org/p4pb12873429/p4pb12873429.jpg

Since my calipers have a large "belly" I can't use the Shimano F203
flat-lined adaptor but must use some that seem only available from
China. Looks like they will adapt from 160mm PM to 203mm though specs
are, as usual, sorely lacking:

https://erpimgs.idealhere.com/ImageF...963c864243.jpg

The rear is native 160mm and currently has a 160mm rotor. I'd like to
upgrade both front and back to 203mm or 8". Mostly to reduce rotor
heating during long descents.

--
Regards, Joerg

http://www.analogconsultants.com/