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Building up a 29er from second hand parts.
Came to fit the Hope M4 front caliper to the Rockshox Reba and 180mm disc and hit a bit of a problem.
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The back face of the caliper mount on the forks is about 13mm from the disc as normal, but the caliper appears to be too thick at the mounting points.
Is there some sort of 180 to 180 stepped adapter I should be using ?
Or should I just get the caliper machined away at the bolt holes to match the rear one. There's plenty of thickness of metal there.
The caliper looks unusual in those pics What number is stamped on it? Has the caliper been modified?
you may need a new caliper half, looks like it has a boxxer or similer half on, crc had some different ones in stock not long ago, a phone call to hope may help
from the pic, it looks like a number 6 caliper half. I think CRC have a number 8 in stock which would fit a 205 rotor. To fit a 185 you'll need a number 3
Right, I'm learning stuff about Hope brakes I should have known before I bought them. 🙄
If the photo wasn't so fuzzy, you would see that it says M4 over 6 at the bottom.
The relevant page on Hope's site is blank, but looking at [url= http://www.chainreactioncycles.com/Models.aspx?ModelID=916 ]CRC[/url], it looks like I have got a caliper to fit Boxxer forks.
Luckily, CRC have got Hope M4 caliper halves on sale, reduced from £35.00 to £34.99 😕 although they haven't got the Number 3 that I want in stock.
It looks like taking the measurement off the rear caliper and getting the front one machined is going to be the best option.
might be worth looking on ebay or putting a wtd ad on the classifieds here for a mono m4 caliper, it will work with your old lever no problem no silly new halfs needed just normal mounts, seen em go for less than crc's price for a caliper half in the past,
Just out of curiosity, have you tried mounting it and then measuring to see what size rotor it would take?
Here's a link to the [url= http://www.hopetech.com/technical/tab_fitt.htm ]caliper number chart[/url] from Hope.
Thanks, Three_Fish. I'd looked on Hope's site and missed that.
It confirms that I've got a 6 and want a 3.
Onzadog, it's not the diameter that's a problem. If I was to mount the caliper on the forks, it would end up about 10mm too far to the right, closer to the spokes. Boxxer mounts must be about 10mm further to the left than standard.
khani, I'll have a look, but a friend of mine is in to bikes and runs his own engineering business, so getting mine machined may be the easiest option if nothing turns up soon.
Never understood why Boxxers had to be so different! Good luck with it.