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GaryTheSnail

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Discussion starter · #1 ·
I need to buy some 180mm Centerlock rotors and I see that Shimano has several different model with different prices. I'm just a casual rider, just trails, no off road, no downhill. I don't need anything fancy, just brakes that work (however, I do think the XTR rotors are very sexy looking). Honest, even the cheapest SM-RT30 would probably be OK. What do you recommend?
 
Personally I'd go with anything from the RT6X level on up, they use a nicer splined section which gives a better fit on the hub. The cheaper rotors use a stamped steel center section which doesn't fit on the splines as well and almost always has some play. Doesn't really affect how the brakes work, but slop in the hub to rotor interface annoys me.
 
Discussion starter · #6 ·
Personally I'd go with anything from the RT6X level on up, they use a nicer splined section which gives a better fit on the hub. The cheaper rotors use a stamped steel center section which doesn't fit on the splines as well and almost always has some play. Doesn't really affect how the brakes work, but slop in the hub to rotor interface annoys me.
A quick check of prices shows the RT64M only a few bucks more than the RT30.
 
Only one tool needed, depending on which lockring you have you'll either need a cassette lockring tool or a bottom bracket tool, you won't need both tools unless both wheels use different lockrings.
Yup. The cassette lockring would be the one to get if you have regular qr axles. If you have thru axles, then get the bb style lockring.
 
Now I'm confused. Why does the attached Shimano document show both tools?
I think they are trying to make the point that 40 Nm is required for CL, regardless of the tool type. They also show a hex bolt arrangement for completeness. Only one type of tool is required for a particular hub.

One point is if you care to carry a CL tool in your backpack, the bb tool is more portable. This tool corresponds to larger axles, so the universe is in alignment on this one.
 
Discussion starter · #12 ·
I think they are trying to make the point that 40 Nm is required for CL, regardless of the tool type. They also show a hex bolt arrangement for completeness. Only one type of tool is required for a particular hub.

One point is if you care to carry a CL tool in your backpack, the bb tool is more portable. This tool corresponds to larger axles, so the universe is in alignment on this one.
I guess they way they show it is misleading. They show two different tools in the section for the CL installation, which is separate from the six-bolt section.
 
I guess they way they show it is misleading. They show two different tools in the section for the CL installation, which is separate from the six-bolt section.
Naw like the others said, the 20mm uses a different type of CL lock ring because the axle is different - I have one of those 20mm front in Zee trim and the diagram makes perfect sense to me....
 
I guess they way they show it is misleading. They show two different tools in the section for the CL installation, which is separate from the six-bolt section.
Two tools for two types of lockrings, a cassette tool won't work on a lockring that's made to use a bottom bracket tool and a bottom bracket tool won't work on a lockring that's made to use a cassette tool.



 
Discussion starter · #16 ·
Thanks for the pics, The bike has a Shimano Alfine 8 hub which uses a bolt-on axle, so I suspect it's got the BB-style lockring, but your pics will help me identify it for sure.


If I need the BB tool, is the Park BBT-9 equivalent to the Shimano TL-FC36?
 
Discussion starter · #18 ·
OK, with a solid axle I need the TL-FW30 tool. The guy at the bike company tells me the FR-5 won't reach, and the FR-5G and TL-LR15 can't be used because of the center pin.

Also, back to my original question, there is one BIG difference in Shimano rotors. The RT6X and up are "narrow" rotors, meaning the pad track width is narrower than the RT5X and below "wide" rotors. So, the wide calipers (most mechanicals including the BB5 and BB7, and my Tektro Aquila) will wear on the rotor arms, not a good thing.
 
Also, back to my original question, there is one BIG difference in Shimano rotors. The RT6X and up are "narrow" rotors, meaning the pad track width is narrower than the RT5X and below "wide" rotors. So, the wide calipers (most mechanicals including the BB5 and BB7, and my Tektro Aquila) will wear on the rotor arms, not a good thing.
Not sure of your question, as your statement is probably correct, that running narrow track disc with wide(r) pads will likely to cause uneven disc/pad wear. If you use multiple concave washers, you maybe able to position the caliper so the pads don't run over the arms. But you may have to grind the top edge from time to time. I have RT5 and perhaps it's heavier than RT6 but I can't really tell while I'm riding the bike :)
 
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