Differences in hope c2 brakes

[dan28]

I have some hope c2 s that are running IS Mount number 3 calipers
The calipers also have an o on them does this mean they are open system?
I also have what I think are c2 post mount calipers can I swap the calipers over
How do you tell if they are open or closed system

 

[dyna-ti]

Closed and Open.
O2 are Open 2, C2 are Closed 2.
It refers to the type of system.
Today's brakes for example are open system.
What it means to RBers that you need an O lever for an O caliper and a C lever for a C caliper
So basically to answer your question, calipers which just have HOPE on them are C2

The 2 I believe refers to the number of pistons

How you tell is at the lever end and the fact the O caliper has an O cut into it.
The O (open)lever has no adjuster knob

O2 lever -


C2 lever -


Internally on the O2 caliper as opposed to the C2 caliper, the O2 caliper has no internal spring to pull the piston back into the caliper when you release the lever. The O2 piston retracts because the seals flex outwards and the tension when released retracts the piston, which is why O2 seals should be replaced more often than C2 as they are more likely to wear and its critical they be in good condition.

O2 pistons are considerably easier to get out the caliper when changing the seals. C2 piston removal is fraught with horrors.

 

[stevet1]

Just to add you can get C2 levers that resemble the 02 levers shown above but with the addition of the adjuster knob which is needed on the closed system as the pistons do not self align when the pads wear. I believe the top levers are called the sport lever, and the bottom the pro lever which give slightly more power.

 

[boxxer]

the lever type changed in 2001 when the E4 came out, before that they were all the longer style, Hope then branded them Pro (expensive) and Sport (less expensive)

The calipers are as dyna said, the #1 was standard with various mounts, it then became a bun fight in the later 90's as everyone tried to create their own frame tabs / fork tabs, IS helped with this with a lot of exceptions, #2 being the non disk long rear, 11-74 was hayes and there was a 9-74 as well, #3 was IS, #4 was marzocchi / Formula standard, #5 was IS but for smaller disks, #6 was Boxxer fit - there were 7 to 14 calipers as wll, no wonder we ended up with flat mounts!

 

[dan28]

Thanks I understand now
So in answer to my question I can't run the c2 calipers with the o2 levers
So I guess I ll sell the o2 brakes complete

 

[dan28]

One other thing if the system is open an the bike is stored upside down can this effect the fluid
Just thinking I once had some x2 levers an had nothing but trouble with them