Roadie turned to Disc Brakes

quarkrad809

A few years ago I bought a hydraulic disc brake based bike for my winter beast. Time to change the fluid and replace the pads but I'm in a new world of what to buy. The replacement fluid kit is easy to buy but there seems little information (or too much!) when it comes to the pads. I have shimano RS 8020 brakes and I believe the fin type of pads on the front. I'm not sure what tI need to buy. I get the impression certain pads fits all sorts of models but I don't know what is what. I think I'm getting close and then there is the MBT/Road confusion. Also - when it comes to possibly buying non shimano brands it gets worst (some people suggest one never buys shimano pads but other non branded types). It also appears (I think) you do not have to fit the fin type if you want to. (Replacement rim brake pads was a lot less confusing). Any help appreciated - brakes are getting a bit spongy and near to the handlebars!

billycool

These should fit but have a look at your existing pads.

https://www.sigmasports.com/item/Shimano/L03A-Disc-Brake-Pads-Resin/N1UL?s=1

You don't need the fins - they are meant to help keep things cool but as a mountain biker I've never seen a benefit and they are bit of a gimmick.

You can fit other brands as well - I never used branded pads so don't worry about that.

There are different compounds available as well. Similar thread here:

https://forum.bikeradar.com/discussion/13109606/which-disc-brake-pads#latest

janwal

https://gorillabrakes.com/
I have used this company for a couple of years now for my Sram disc pads after seeing a recommendation. I use the mixed compound. Have not had any problems at all. Friend use them for his Shimano discs.They wear fairly quickly around the Huddersfield hills! I don’t mind though as they are so cheap. Drop them an email,they reply quickly and are really helpful.

thistle_

Agree with the comment about finned pads - mine came with finned and they looked good but they didnt last that long, replacements were really expensive and at the time nobody made aftermarket finned pads so I've just used non finned and not really noticed any difference.If

I get mine from Uberbike - customer service has always been brill.

If the pad is the correct shape then it can be used. Most websites will have a lookup chart or table to tell you which ones you need and multiple brake calipers use the same shape pad.

If the levers are spongy then they need bleeding but you might not need to change the fluid if its not that old (you just need a small amount of fluid to bleed them).

Out of interest, are both your front and rear pads wearing at a similar rate? My bike's eating through pads on the rear but the front last ages. On my MTBs it's the other way around.

pilot_pete

To find out which ones fit your calipers, use this Shimano guide https://bikecheck.shimano.com/global/en/parts-selectors
Once you have the Shimano part number you can get equivalents from the likes of Uberbike if you want cheaper. As far as wear is concerned, original resin pads wear quicker in cruddy, winter conditions than sintered pads. You pays yer money and makes yer choice...

PP

quarkrad809

Thank you all for your help - much appreciated - I have ordered some Uberbike pads. I need a bleed kit and most, if not all, kits seem to be from mtb suppliers. I have seen this kit many times https://www.amazon.co.uk/Bicycle-Hydraulic-Mineral-Shimano-MAGURA/dp/B07NYS47T8/ref=sr_1_20?keywords=shimano+bleed+kit&qid=1578559476&sr=8-20 with differing reviews but on the whole it appears positive (not going to get much use!). I'm struggling to find out if this kit would be suitable for my ultegra rs8020 system. It looks like many mtb systems use funnels but is there anything special about my 'rs8020 road' brake thread that needs a specific funnel?

quarkrad809

Sorry - another question. Looking at the Shimano 1 ltr mineral oil - but keep reading many people use other mineral oil because the Shimano is so expensive. At the same time I read 'horror stories' about rubber seals perishing if using non-shimano oil. What do you guys use?

billycool

quarkrad809 said:

Thank you all for your help - much appreciated - I have ordered some Uberbike pads. I need a bleed kit and most, if not all, kits seem to be from mtb suppliers. I have seen this kit many times https://www.amazon.co.uk/Bicycle-Hydraulic-Mineral-Shimano-MAGURA/dp/B07NYS47T8/ref=sr_1_20?keywords=shimano+bleed+kit&qid=1578559476&sr=8-20 with differing reviews but on the whole it appears positive (not going to get much use!). I'm struggling to find out if this kit would be suitable for my ultegra rs8020 system. It looks like many mtb systems use funnels but is there anything special about my 'rs8020 road' brake thread that needs a specific funnel?

Generally, Shimano brakes use a Shimano funnel.

This PDF suggests that your brakes would be the same (I've not read it in it's entirety but look at pages 25 and 26)

https://si.shimano.com/pdfs/dm/DM-RADBR01-03-ENG.pdf

The kit that you have linked to has a funnel in it, so should work.

As for mineral oil. I use genuine stuff as I just don't want to take the risk of having no brakes or damaging something. It is expensive and I'm sure you *could* find other options.

i.bhamra

I think the bleed port on R8020 levers is slightly different than earlier (and also possibly MTB models) you may need an adapter to make the funnel work (that kit looks like it may have that covered though).

As long as you use mineral oil you shouldn't have a problem with seals, the issue tends to arise when people use DOT fluid as used in SRAM systems with Shimano and vice versa.

The Rookie

The right Mineral oils are fine, you need Citroen LHM oil. It's DOT brake fluid that kills them.

Why are you bleeding them anyway? If they work fine there is no need to bleed them. In fact i haven't bled the brakes on the front of my MTB in 5 years now, rears I had to do when swapping in a longer hose for a new frame about 18months ago.

yellowv2

Because in the OP’s original post he says the brakes are spongy and the lever is coming a long way back.

quarkrad809

Hmm.... big problem but temporarily fixed it. Retaining bolts would not come out - cutting a long story short (taps, wd40, etc) the soft ali heads came off and I had to drill the bolts out. Good news is that new pads fitted and brakes have a much better feel - I have had to use a split pin for now while retaining bolts are to be purchased. One site says that the same bolts fits M985 / M9120 / R8070 systems and I have seen a BR-M985 Pad Axle & Snap Ring - Y8J798060 for £3.99 and a specific r8070 one for about £7.00. Big difference when buying 2. Can anybody advise if a m985 bolt is the same as that for a R8070? The pictures look like it is the same bolt.

billycool

Split pins work just as will IMO. No idea on the bolt sizes.

thecycleclinic

Slipt pins are a sensible solution .