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I had some Hope Minis sitting around and a spare frame so I've built a new SS.
Hope Minis have had new caliper seals, new hoses and new pads, the calipers have been set up as per the hope web site and used a my little bleeder to re-fill the brakes, I have issues with both brakes catching, front a little and rear a lot, there appears to be enough space for pads and disc.
When I pull the brake lever they only stop the wheel when very close tot he bar but when the lever is released the wheel doesn't spin freely, any ideas as to what the issue could be?
Catching maybe due to slight buckle in the disc's? (is it all the time?)
The power issue sound like they need to be bleed again. Might be worth zip tie-ing the levers to the bars overnight, to force any trapped air through first.
Constant catching rather than buckled disc, almost like the pads are coming out to meet the disc and not retreating.
If I zip tie where will it force the air? Lever/reservior or caliper?
sticky pistons [ not moving freely] and a bleed needed.
If I zip tie where will it force the air?
Hopefully out of the caliper and into the reservoir (Not a guaranteed fix, but worth a try), and indeedy if the disc isn't buckled, the pistons can't be retracting correctly. If you don't want to take them to pieces again, try lubing the pistons with DOT fluid & moving them back and forth (press lever, lever pads back & repeat), though fitting old pads is worthwhile whilst trying to perform this.. as it's hellishly messy and you will get fluid on the pads
They seemed to be OK prior to re-bleeding, even did red rubber grease put them new pheno whatever pistons in, hope I don't have to start dismantling too much.
oops, double post.
Probably just need bleeding. I just use the 'loosen nipple-squeeze lever-tighten nipple-release lever-top up reservoir as required' method.
On my old style mini's I found the nipples were letting air back in via the thread when I released the lever, some of that plumbers thread tape sorted it out. I only realised what was wrong as I noticed brake fluid weeping from the nipple when pulling the lever hard.
Also, if you are using aftermarket pads such as superstar, sometimes the paint on the backing pad makes them too thick to clear the disc even when the pistons are fully retracted, you just need to scrape the paint off. Not had to do that for ages, mind.
Was getting a bit warm in the sun yesterday they are Disco kevlar on the rear and did seem quite thick, I'll take another look to make sure the pads are retracting fully and have enough space to spin freely then re-bleed.
Usually taking the pads out and pushing the pistons as far back in as they'll go works - I'm rarely brutal enough with them. Might also be worth checking the spring clip is doing something.. you get a new one in 'official' pads so I usally put a set of them in every year or so to refresh it. If it's the spring it's usually enough to notice in the bike stand but OK when riding, and it'll settle down after a few rides.
take pads out and squeeze the lever slightly as pistons seem to push back easier after they have been out a bit
Cheers all, a little more tinkering this evening, re-bled and different shims and running much better.
Still a bit of rub but I think it'll be betterer once the pads are settled in.