Not sure if this is in the right section, are hope brakes interchangeable with the rotors ?
i have seen various different calipers which have 6 bolt rotors and 5 bolt rotors etc...
is it possible to buy a front hope m4 with 185mm rotor then change the rotor size to 160mm and everything works fine or will i need o buy somthing else or calipers to match etc,, ?
same for another front i've seen fairly cheap yet it has 203mm rotor, i'm really looking for 160mm front and back..
Disk brakes are a bit of a mine field if your not sure of what your looking at. I'll try to explain as best I can for you.
When you buy a brake it has a size associated with it. Say, for example 160, 180 or 203mm. This only relates to the Disk size. The caliper will be the same size in either case. You will (or should) get an adaptor with the brake to fit between your fork/frame and the caliper. This adaptor varies in size to offset the caliper to fit the associated rotor. The brake disk (or rotor) can have various methods of fitment. It all depends on the type of hub your fitting it to. In my experience 6 bolt is the most common although shimano uses both 6 bolt and a splined hub to fit disks.
The caliper could be either IS (International Standard) or Post mount. IS uses bolts through tabs on the fork or frame and go through at 90 degrees to the wheel. You usually have to use shims to ensure the caliper sits correctly around the disk. Post Mount bolts in line with the wheel. The holes on the caliper are usually elongated to make setting up the brakes easier.
If you want 160 front and back then the best thing to do is to go straight for that size. It would probably be more expensive to buy bigger brakes and then change the disk's (and maybe adaptor) for smaller.
Have a look at these. They are available in 160mm and the price is for both front and rear. The calipers are post mount and the rotors are 6 bolt. Have a look around and see what you can find.
thanks for the response i guess i was more then a little sketchy on infomration..
i have just got a cheap bike and was working on buying a few more personal choices in parts, once i have the ideal set up i'll then look into frames etc...
currently have hays sole (or solo not sure), 180 front 160 rear fitted with IS mount on to rock shox tora u-turns.
idally i like the look of the hope mini's, m4 etc.., or the formula's, looking around there are some hope's around with IS mounts yet the rotors were either 203mm or 180mm, i'd prefer 160 on front and rear for just xc trail's..
i really liked the look of some titaium coated rotors (160mm with a kind of gold'ish colour) hence why i asked about swapping out the rotors with calipers and sizing etc..
i too liked the Hays setup that you have shown yet i've heard horror storeys about servicing them..
I've serviced Hayes calipers berore but not the lever. The caliper was OK but I needed circlip pliers (which I didn't have at the time). The new ones look much easier to service.
The inside of a Hayes HFX9 looks like this - no circlip pliers needed on this one:
This had to be pulled open to replace one of the pistons which either had the spring that holds the brake pad fail, the pad fall out and the piston get torn up against the disk or the nail head in the middle of the piston fail, the pad fall out and the piston get chewed up against the disk (While on the Fort William DH track).
Either way after seeing this failure and the number of people who've had seized pistons in the caliper (Almost everyone I know who bought Hayes brakes - It happens after a few years use) I'd be slow to buy them. They also feel very wooden at the lever (Though that's a personal preference thing).
I'd buy either Shimano disks for serious reliability and safer (Mineral Oil) brake fluid or Formula ORO's for fantastic stopping power - for a given disk size they're the most powerful brakes I've used apart from Magura Gustavs and they definitely weigh less than those.
