Does this disc brake and rotor look correct?
08-08-20, 08:24 AM
#1
Junior Member
Thread Starter
Does this disc brake and rotor look correct?
Just installed this hydraulic brake on an All City Space Horse frame. After bedding in the brake, it looks like the pads aren't grabbing the whole outer part of the rotor. Also the very top part of the pads aren't hitting the rotor at all. The pads are definitely installed correctly with the clip pin in place, they can't really move at all. It's a SM-RT66S 160mm rotor, Tektro IS-PM adapter, and BR-M6000 brake.
Do I have everything set up correctly here? The brake has great stopping power, but I thought I'd check to make sure I didn't do anything stupid... The front brake seems to be wearing the rotor in the correct place, fyi.
Do I have everything set up correctly here? The brake has great stopping power, but I thought I'd check to make sure I didn't do anything stupid... The front brake seems to be wearing the rotor in the correct place, fyi.
08-08-20, 09:12 AM
#2
Banned
Looks like the caliper is a bit high, maybe 3~4mm .. not getting full pad to disc contact..
but it's the back wheel, front is where the mass shifts decelerating.. that's where the action is..
but it's the back wheel, front is where the mass shifts decelerating.. that's where the action is..
08-08-20, 09:39 AM
#7
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Not being there with a wrench to tinker on it all I can say is that doesn't look right. The pads shouldn't be that high up and off the edge of the rotor. Something isn't right. It will probably still stop you just fine, but you're going to experience faster pad wear for sure. It looks like the rear should roll down into the bracket mount further. Good luck,
08-08-20, 09:51 AM
#8
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Thread Starter
Here's the front, better but not quite right I think. I'm going to buy the Shimano adapter, if it's still not right I'll talk to all city.
08-08-20, 11:08 AM
#10
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08-08-20, 11:16 AM
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edit: I had it backwards - your current rear adapter is for a 180mm rear rotor and you need to get an adapter for a 160mm rear rotor.
Last edited by tyrion; 08-08-20 at 11:22 AM.
08-08-20, 11:22 PM
#13
Senior Member
I had a similar problem with my front brake when I built my bike, I had two 20mm adapters. I realized this after reading https://www.analogcycles.com/true-fa...rake-adapters/
160mm front rotor: +0 adapter
180mm front rotor: +20 adapter
200mm front rotor: +40 adapter
140mm rear rotor: +0 adapter
160mm rear rotor: +20 adapter
180mm rear rotor: +40 adapter
180mm front rotor: +20 adapter
200mm front rotor: +40 adapter
140mm rear rotor: +0 adapter
160mm rear rotor: +20 adapter
180mm rear rotor: +40 adapter
08-09-20, 11:02 PM
#14
Senior Member
I have seen this before as well. Its just sloppy manufacturing. If you want to fix it you have to remove metal from the adapter. Make sure you are still square when youre done machining or <gasp> grinding. 
08-10-20, 01:14 AM
#15
Senior Member
Just installed this hydraulic brake on an All City Space Horse frame. After bedding in the brake, it looks like the pads aren't grabbing the whole outer part of the rotor. Also the very top part of the pads aren't hitting the rotor at all. The pads are definitely installed correctly with the clip pin in place, they can't really move at all. It's a SM-RT66S 160mm rotor, Tektro IS-PM adapter, and BR-M6000 brake.
Do I have everything set up correctly here? The brake has great stopping power, but I thought I'd check to make sure I didn't do anything stupid... The front brake seems to be wearing the rotor in the correct place, fyi.
Do I have everything set up correctly here? The brake has great stopping power, but I thought I'd check to make sure I didn't do anything stupid... The front brake seems to be wearing the rotor in the correct place, fyi.
Shimano has 2 types of rotrors and calipers: wide and narrow. Most other manufacturers use only the narrow variant. They are exactly what they suggest: narrower or wider pads and rotors.
Your rotor looks to me like an RT66, which is a wide rotor. Your Deore brakes are narrow type.
You can't use a wide caliper on a narrow rotor as the pads wouldn't have proper contact (would contact the arms), but you can use a narrow caliper on a wide rotor. In the latter case though, the pads won't contact the whole rotor surface as they are narrower, which is the effect you have noticed.
I replaced the wide MT400 brakes that came in my mountain bike with MT520's which are narrow type brakes and have the same effect. Maybe not as exaggerated as your rear wheel... you could try to find an adapter that's not so high for that if it bothers you, but I think it's ok.
You can look at this spreadsheet for a compatibility list: https://docs.google.com/spreadsheets...29c/edit#gid=0 the "wide" variants are called "B" in this spreadsheet.
Last edited by Amt0571; 08-10-20 at 01:20 AM.
08-10-20, 06:20 AM
#16
Junior Member
Thread Starter
There's no sloppy manufacturing here, neither there is a tolerance problem nor wrong adapter used.
Shimano has 2 types of rotrors and calipers: wide and narrow. Most other manufacturers use only the narrow variant. They are exactly what they suggest: narrower or wider pads and rotors.
Your rotor looks to me like an RT66, which is a wide rotor. Your Deore brakes are narrow type.
You can't use a wide caliper on a narrow rotor as the pads wouldn't have proper contact (would contact the arms), but you can use a narrow caliper on a wide rotor. In the latter case though, the pads won't contact the whole rotor surface as they are narrower, which is the effect you have noticed.
I replaced the wide MT400 brakes that came in my mountain bike with MT520's which are narrow type brakes and have the same effect. Maybe not as exaggerated as your rear wheel... you could try to find an adapter that's not so high for that if it bothers you, but I think it's ok.
You can look at this spreadsheet for a compatibility list: https://docs.google.com/spreadsheets...29c/edit#gid=0 the "wide" variants are called "B" in this spreadsheet.
Shimano has 2 types of rotrors and calipers: wide and narrow. Most other manufacturers use only the narrow variant. They are exactly what they suggest: narrower or wider pads and rotors.
Your rotor looks to me like an RT66, which is a wide rotor. Your Deore brakes are narrow type.
You can't use a wide caliper on a narrow rotor as the pads wouldn't have proper contact (would contact the arms), but you can use a narrow caliper on a wide rotor. In the latter case though, the pads won't contact the whole rotor surface as they are narrower, which is the effect you have noticed.
I replaced the wide MT400 brakes that came in my mountain bike with MT520's which are narrow type brakes and have the same effect. Maybe not as exaggerated as your rear wheel... you could try to find an adapter that's not so high for that if it bothers you, but I think it's ok.
You can look at this spreadsheet for a compatibility list: https://docs.google.com/spreadsheets...29c/edit#gid=0 the "wide" variants are called "B" in this spreadsheet.
08-10-20, 06:20 AM
#17
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The RT66 is a narrow rotor from the SLX family.
https://bike.shimano.com/en-US/produ...0/SM-RT66.html
https://productinfo.shimano.com/#/co...460&acid=C-461
The adapter looks to be a Tektro Lyra L-3 (180mm front / 160mm rear) and should be the correct size, it's not a 180mm rear adapter which has been suggested, if it was a 180mm adapter with a 160mm rotor, the pads would be overhanging the rotor by 10mm.
https://www.tektro.com/products.php?p=108
If the pads are overhanging to outer edge of the rotor by 1mm (which has been stated), there must be something slightly out of spec somewhere.
08-10-20, 06:24 AM
#18
Senior Member
I don't have an RT66 rotor at hand, however, acoording to the spreadsheet I posted, it's compatible with wide calipers, so it's a wide rotor.
Based on the pictures I would also say it's wide, as on the picture of the front brake you can see it fits the whole pad with room to spare.
Based on the pictures I would also say it's wide, as on the picture of the front brake you can see it fits the whole pad with room to spare.
08-10-20, 06:26 AM
#19
Senior Member
This is the first I'm hearing of the two rotor/caliper types, I had no idea! What's the motivation for having two different types? Also it's strange because the SM-RT66 is listed as a compatible rotor on the BR-M6000 page: https://bike.shimano.com/en-EU/produ.../BR-M6000.html
All wide rotors are compatible with both wide and narrow calipers, but you can't use a narrow rotor with a wide caliper. There should be no problems using a wide RT66 with narrow Deore brakes.
08-10-20, 06:28 AM
#20
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Thread Starter
I don't have an RT66 rotor at hand, however, acoording to the spreadsheet I posted, it's compatible with wide calipers, so it's a wide rotor.
Based on the pictures I would also say it's wide, as on the picture of the front brake you can see it fits the whole pad with room to spare.
Based on the pictures I would also say it's wide, as on the picture of the front brake you can see it fits the whole pad with room to spare.
Also I'm very glad I took a lucky guess and got the rotors that work with both resin and metallic pads!
08-10-20, 06:34 AM
#21
Senior Member
I don't have a narrow mountain bike rotor at hand to compare, but the Avid Centerlines on my road bike measure 1.5cm at the widest point.
08-10-20, 06:47 AM
#22
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I don't have an RT66 rotor at hand, however, acoording to the spreadsheet I posted, it's compatible with wide calipers, so it's a wide rotor.
Based on the pictures I would also say it's wide, as on the picture of the front brake you can see it fits the whole pad with room to spare.
Based on the pictures I would also say it's wide, as on the picture of the front brake you can see it fits the whole pad with room to spare.
https://productinfo.shimano.com/#/co...460&acid=C-460
Whether it's narrow or wide doesn't really matter, if the pads overhanging the outer edge of the rotor by 1mm, something must be slightly out of spec somewhere.
Last edited by cobba; 08-10-20 at 06:54 AM.
08-10-20, 06:51 AM
#23
Senior Member
Shimano list it as narrow rotor.
https://productinfo.shimano.com/#/co...460&acid=C-460
Whether it's narrow or wide doesn't really matter, if the pads overhanging the outer edge of the rotor by 1mm, something must be slightly out of spec somewhere.
https://productinfo.shimano.com/#/co...460&acid=C-460
Whether it's narrow or wide doesn't really matter, if the pads overhanging the outer edge of the rotor by 1mm, something must be slightly out of spec somewhere.
08-10-20, 06:53 AM
#24
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Thread Starter
I measured the rotor width on a couple of bikes I have with wide rotors (shimano RT10 and RT53). Both are around 2cm at the widest point.
I don't have a narrow mountain bike rotor at hand to compare, but the Avid Centerlines on my road bike measure 1.5cm at the widest point.
I don't have a narrow mountain bike rotor at hand to compare, but the Avid Centerlines on my road bike measure 1.5cm at the widest point.
Shimano list it as narrow rotor.
https://productinfo.shimano.com/#/co...460&acid=C-460
Whether it's narrow or wide doesn't really matter, if the pads overhanging the outer edge of the rotor by 1mm, something must be slightly out of spec somewhere.
https://productinfo.shimano.com/#/co...460&acid=C-460
Whether it's narrow or wide doesn't really matter, if the pads overhanging the outer edge of the rotor by 1mm, something must be slightly out of spec somewhere.
I've ordered the shimano is/pm adapters, we'll see if they fit better. If not I'll grind down the surface where the caliper mounts to get things looking correct.
08-10-20, 06:55 AM
#25
Senior Member
Looks like the RT66's are about 15mm wide as well.
Totally agree, all that matters is that the pads fully contact the rotor. If the rotor overhangs the edge of the pads some I'm thinking that's ok?
I've ordered the shimano is/pm adapters, we'll see if they fit better. If not I'll grind down the surface where the caliper mounts to get things looking correct.
Totally agree, all that matters is that the pads fully contact the rotor. If the rotor overhangs the edge of the pads some I'm thinking that's ok?
I've ordered the shimano is/pm adapters, we'll see if they fit better. If not I'll grind down the surface where the caliper mounts to get things looking correct.
