New Fangled Hope Disc Brakes…

[FZRIP]

I picked up a new bike yesterday, 2003 Explosif.
I’ve never had disc brakes before, or anything hydraulic and I need some help to understand their workings.
I don’t know which model they are.
The rear lever moves a lot more than the front, almost touching the bars.
The brakes still work amazingly well, I’ll be over the bars if I’m not careful being used to old cantis.
What do I need to do to reduce the lever travel?
Thanks in advance for any advice.

 

[clubby]

They are Hope Minis. Had a few sets of those back in the day.
Couple of possible reasons for what you describe. Rear pads could be really worn out or the fluid may be needing bled and levels topped up. Bleeding is a really easy job on these brakes and I'd probably be doing that at both ends anyway if the bike has been sitting for a while. There is also a grub screw in the silver part of the lever. This sets reach and worth checking if equally adjusted on both levers.

Manual is here

https://www.hopetech.com/_repository/1/documents/userguide_printed_2002-11.pdf

Loads of videos on youtube regarding the bleed process.

 

[FZRIP]

How can I check the pad wear? Is there a known pad thickness or something?
Any recommendations for new pads?

 

[Cloverleaf]

Pads when new will usually be around the 2-2.5mm mark. Some are slightly thicker, some slightly thinner. They're twenty-ish years old now so there's always a chance that they need some TLC but they're generally pretty reliable. I'd give them a bleed and lubricate the pistons first and foremost to make sure the basics are covered before worrying about anything more serious. They look in good condition. They're the original Mini caliper with what's also called the Mini lever, not to be confused with the later Mono Mini which has a one piece caliper, identified by a black caliper body and gold piston cap.

For piston lubrication use this (or some brake fluid, or silicone spray), as it's what Hope themselves recommend and always have: https://www.the-landscape-centre.co.uk/s00001540.html - it's £15 a bottle from them for 250ml or £15 for 50ml from a bike shop. Push the pistons out without the pads and apply with a brush to the pistons and seals. Push the pistons back in, pump them out, apply some more lube and repeat the cycle a few times until both pistons are coming out evenly. Be careful not to let the pistons come all the way out unless you're comfortable bleeding them (you won't break anything by the piston coming out, but you will need to bleed them to get them working again).

It could be the rear pads are just low and the pistons are sticky so aren't staying out enough to compensate for the previous pad wear, giving the longer lever feel, They should have about 10mm free travel if they're working right, give or take a few mm. Lubricating and re-setting the piston (i.e if the piston is sticky) should have that working okay.

 

[Cloverleaf]

Also, to add, if you are bleeding them then I'd recommend Motul RBF600. Yes, it's Dot 4 rather than Dot 5.1 but the specs are better, and the viscosity lower. The only disadvantage is that it doesn't go to -30 or something like 5.1, so doesn't quite tick the box. The lower viscosity keeps the lever feel lighter in motion, and return slightly quicker, and is less hygroscopic. You can go for RBF660 if you want to be flash but it only gives you a few degrees more at the top end and you're just not getting there on a trail bike, I promise you. Even on the car which I've had discs glowing I've not needed the 660. I've never found Hopes to need regular bleeding unlike some brands, but it seems to last longer than 5.1 before it starts to feel funky.

And if you do need seals then these are the caliper ones: https://www.biketart.com/products/h...MInu6D2rbQigMVGqRQBh3D9zwLEAQYBCABEgLHHfD_BwE

and these are the lever ones (if the kit includes a diaphragm of that shape, it's the right one):

https://www.swinnertoncycles.co.uk/...m_medium=affiliate&utm_campaign=genieshopping

and this cap will work with either the Hope pot or Shimano and other generic ones to make bleeding the brake easier. It's not essential but it means you don't need to fill the m/c up quite so frequently while pumping the fluid through.

https://www.biketart.com/products/h...MI3MfAu7fQigMVQJdQBh3Dqg4uEAQYByABEgL9wfD_BwE

 

[FZRIP]

Thank you for your help.
I notice that there’s a tiny little bit of interference of the rotors and pads, is this something to be expected? Or something that can be addressed with the procedures you mentioned?

 

[highlandsflyer]

Have you ridden it a fair bit?

 

[FZRIP]

Have you ridden it a fair bit?

Not yet, just around the block…
“stuff” keeps using up all the bike time at the moment. How come holidays are so busy?

 

[highlandsflyer]

I would check the pads. If there is a little meat left give it a good ride. Minor rubbing is often settled with a ride.

 

[highlandsflyer]

By the way, congrats on an excellent buy!