Anyone know anything about disc brakes?

Did my first bleed to sort out daughter's bike that she's been nagging me to get functioning. Was surprisingly straightforward and worked. Yay!

I'm sure this is a really dumb question, is there any difference between a shimano front and rear IS to post mount adaptor ? I appear to have bought two front adaptors, but there wasn't an option for a rear one and when I google a picture of them they look the same as a front one ?

IIRC it's usually 160F/140R hence if you want to run 160 rear you need a 180F/160R one. Or did I remember wrongly?

@HousecatHST and @coventry_eagle I think for some weird reason, instead of just having 0mm, +20mm and so on adapter, Shimano labels them up as front 160mm (ie 0mm) rear 160mm (ie +20mm) and so on.

I can kind of see what they're trying to do and it'd be fine if everywhere stocked the full range but instead of holding 2 of every size adapter most places just stock the front range or make up a selection of front and rear adapters that covers the commonly needed sizes so you end up looking for and not finding what you need because what you need is a +40mm adapter to run a 180mm rotor on the rear but the shop only has a 200mm front adapter.

I think it's Avid that label them up with the front and rear sizes ie 180f 160r.

I'll sure I have a couple of 180F/160R adaptors in my spares. I'm based in SE1 and you can have them for a 4 pack of beers.

I'm still confused, sorry! so I was planning to run 160 disc front and rear, so I'd bought two 160 adaptor. Is that incorrect ?

Yes. Probably. If they’re fronts you’ll need a 160 for the front and a 180 for the rear.

I'm going to buy a 180 just in case, I might even go to a bike shop and see what they think

You bought 2 160 front which are also 140 rear. So you have to buy a 180 front which will be a 160 rear.

Hmmm as clear as mud, I explain the issue to the lbs and they gave me this for the rear.
Now I know they’ve got them in stock I’ll take my chance with the front one.

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Why is there not a decent chart showing the shape and applications of the different is-post adapters?

Thought I’d found a decent hand written one but one of the adapters was wrongly labelled, it said R180mm on the adapter but was labelled as Rear 160mm. How do you get that wrong? It’s right there!

Shimano do sell separate F180 and R160 adapters, but the differences wouldn't stop you using them interchangably.

re-cabling the bike I managed to loose the screw, washer and small metal pad that hold (pinch bolt?) the cable in a TRP Spyre brake... 🙈 any ideas where I can get a spare? tried SJS and TRP spares without much luck... @mdcc_tester @edscoble do you have a clue? any help to avoid having to buy a whole new brake would be really appreciated!!

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I started reading from the beginning, then i gave up, sorry if i'm repeating.

I'm adapting my titanium rim brake frame for ultra/long distance riding. Disk brakes seem obvious in order to reduce hand fatigue and also open up options for fork and mudguard clearance. Currently I have good quality long drop trp calipers with deda black rain winter forks.

I realised today that the back brake is pretty much irrelevant and maybe the TRP disk or TRP disk/hydro combo could give me a 'cheap' upgrade to a front disk without changing my whole group set (105 5800) and frame. The frame is a straight 1 1/8" fork. I welcome thoughts on whether this would work, and if it's a good idea.

I'm trying not to spend all the money so would happily stick with rim brakes, and could definitely work with what I have, but if I end up building a dynamo front wheel, I think disk is ultimately the future so don't want to waste money.

Sell the existing bike, buy a new disc brake one.

It’ll be far easier in the long run.

re-cabling the bike I managed to loose the screw, washer and small metal pad that hold (pinch bolt?) the cable

That's a good start. What you want to avoid is removing it completely, as in that case you may lose it.

😁

I've had the TRP hy/rd setup recommended to me by a friend - I know it won't be as good as full hydro but its also < 1/2 the price of new shifters etc.

What are peoples experiences with them - any horror stories to send me running, or usual YMMV? I've been told not as good as full hydro but very bombproof once on.

Full hydro is better

I've been told not as good as full hydro but very bombproof once on.

pretty much this - i have rim, trp and full hydro, and thats pretty much the order of how good they are, rim feels like deadly dangerous now, trp- good, hydro - awesome and want to sleep with it.

There's a disc brake thread with quite a few 'my TRP hy/rd brake is fucked' comments.

edit: wait. this is the disk brake thread. duh.

I've been using my set for 2 years commuting and had to do zero maintenance on them. Only now do I need to change pads.

I've found braking performance as good as my ultegra hydro

Selling as I'm going to flat bar and hydro on the bike.

yeah this is what I remember reading. My current setup is 5700 shifters with a mtb cassette.

My thinking is that if I were to go full hydro (which I am by no means against), it would mean:

• new shifters (200/300)
  
• new RD (since I'd imagine I may end up getting 11spd shifters) no FR as running 1x
  
• new cassette & chain
  
  

not even sure the rear wheel is 11spd so that adds some more food for thought on there. If I can find a hydro part/full groupset used for a good price I'd rather that

I'm a happy Juin Techn R1 user, smaller and cheaper units. You can find failure stories for these too if you look around.

I've got one on my fixed with a disc build, it's not hydro good but rode it this morning and was perfectly good. Not ready to spend £230 on SRAM S900 TT HRD (use a bar end brake on bull horns)

@velohobbit - yup you were in same spot as me a while back, hence i went TRP.
i think at the time, when i specced up buying the gear separately + my time fitting, i could just add a bit more and get a brand new bike (which is what i did in the end, although i then spent much more than i thought i would getting a much higher spec, but the thought process is the same)

i think there are 10sp options now too.