Need help ordering spare rotors for trek allant 8s

Akrotiri

Well-Known Member
Region
Europe
I’m trying to place order for spare front and rear rotors with my local lbs over the phone.

They have the 8s on their showroom floor now but it has the magura brakes so I wasn’t sure what exactly to order. I know their 180mm front and back but the salesman asked if my rotors were center lock or 6 bolt. That’s where I said I would call back.

What exactly should I ask for when ordering spare front and rear rotors for my US spec allant 8s?
 
I’m trying to place order for spare front and rear rotors with my local lbs over the phone.

They have the 8s on their showroom floor now but it has the magura brakes so I wasn’t sure what exactly to order. I know their 180mm front and back but the salesman asked if my rotors were center lock or 6 bolt. That’s where I said I would call back.

What exactly should I ask for when ordering spare front and rear rotors for my US spec allant 8s?
look at the disc. does it have bolts going threw it? if not its centerlock my magura's are bolt on
SI.jpg
 
look at the disc. does it have bolts going threw it? if not its centerlock my magura's are bolt on
View attachment 71838
Going to check now

Edit: it’s definetly like yours 6 bolts around the center on front and rear rotors.

Treks website only specifies 180mm rotors , is it safe for me to assume both front and rear are 180?
 
Last edited:
On my 9.9 the magnet for the speed sensor is built into the rear brake rotor. It is on the inside near center about 1/2" round magnet built into the framework of the rotor. Here is a photo of my spare. It is center lock and you can see the black magnet at 9 o'clock.
20201119_084500.jpg
 
On my 9.9 the magnet for the speed sensor is built into the rear brake rotor. It is on the inside near center about 1/2" round magnet built into the framework of the rotor. Here is a photo of my spare. It is center lock and you can see the black magnet at 9 o'clock.View attachment 71841
I got thru to treks direct online support chat and they confirmed for me it’s front and rear 6 bolt 180mm.

Not sure if mine has the speed sensor there as well but it’s definitely good to know when it comes time to change the rotors so I can warn the service tech. Still only have 1400 miles on the odometer but I’m trying to stock up on spare components based on the unknown were all facing in the next months. Hopefully things and supply chains return to normal by the second quarter of 2021
 
I got thru to treks direct online support chat and they confirmed for me it’s front and rear 6 bolt 180mm.

Not sure if mine has the speed sensor there as well but it’s definitely good to know when it comes time to change the rotors so I can warn the service tech. Still only have 1400 miles on the odometer but I’m trying to stock up on spare components based on the unknown were all facing in the next months. Hopefully things and supply chains return to normal by the second quarter of 2021
you would see it but I doubt it but I would not worry about the rotors. I have 6500 miles on mine and they are fine. you do need a extra set of pads. I get over 2500 miles on a set https://www.amazon.com/gp/product/B01I9ZX0WW/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
 
I'm a fan of having spare parts, but I do agree with @fooferdoggie on this one, rotors should easily outlast multiple sets of brake pads. 180mm 6-bolt rotors are widely available so not a high priority for me to keep a set on hand. However, I do keep a spare set of brake pads in the shop.

I'd suggest regularly checking your brake pad wear and having a spare set of pads on hand. We live in a very hilly little town. My first set of pads were done at 500 miles. I repalced them with a set of semi-metallic pads with large integrated heat sinks. After 1,000 miles they're still going strong. I should get ~2,500 miles out of them at their current wear rate, though I continue to do a visual check on the pads every time I clean the chain.

0402201211a_Film1_20200403071806566.jpg
I use an air compressor to blow dust and dirt out of the caliper fairly regularly and clean the rotors and pads with alcohol if they start to squeal a bit.
 
Going to check now

Edit: it’s definetly like yours 6 bolts around the center on front and rear rotors.

Treks website only specifies 180mm rotors , is it safe for me to assume both front and rear are 180?
Akrotiri: I am concerned about your understanding here. Your statement is that it is "definitely like yours 6 bolts ...", and is seems you are referring to the picture of the previous post which is NOT a 6 bolts rotor but rather a centerlock rotor. A centerlock can still have what looks like 6 bolts but are actually more of a rivet than a bolt.

If it is centerlock, then the front and rear are most likely not the same, as others have replied the rear probably has an integrated magnet. I found the rear with the magnet much harder to find in the US as a retail product.

Also, when it comes to centerlock, there are two types of locking nut which is indicated on Shimano packaging. One has the tool engage internally and the other externally (the threads are the same). Shimano rotors seem to come with the nut, but you could reuse what you already have. For me my Trek has the internal style front and rear, but the new rotor came with internal for the front and external for the back. The important thing here is that you have the right tool for whichever you have or choose to use, and you probably won't have the choice of which one comes with the new rotor.

1605807578363.png
 
Last edited:
you would see it but I doubt it but I would not worry about the rotors. I have 6500 miles on mine and they are fine. you do need a extra set of pads. I get over 2500 miles on a set https://www.amazon.com/gp/product/B01I9ZX0WW/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
I agree with the mileage when changing rotors. Their supposed to last about 6-7500 miles. I went with spare rotors now cause I already stocked up on the stock spec shimano b1os resin pads and kmc while chain. I have 4 pairs (8total) of the brakes pads, 4 extra brand new kmc ebike chains; same spec as the stock ofcourse , 2 more sets of hurricane tires , and 2 HG 500 10speed shimano cassettes again same as stock spec. Now I’m focusing on the components that rarely need to get changed like rotors and even chain rings. I just finished placing the order on the rotors and then asked about the chain ring and the trek tech guy over the phone started laughing. He basically said “what’s going on anything worse about to happen , chain rings last years” lol. Can never be too prepared I guess is my thought process.

Anyway the wait for the rotors and chain ring is only a week surprisingly so since my atran velo came in today I told them them to ship it all out late next week together when the rotors and chain ring come in on wed or Thursday.
 
Akrotiri: I am concerned about your understanding here. Your statement is that it is "definitely like yours 6 bolts ...", and is seems you are referring to the picture of the previous post which is NOT a 6 bolts rotor but rather a centerlock rotor. A centerlock can still have what looks like 6 bolts but are actually more of a rivet than a bolt.

The front and rear are most likely not the same, as others have replied the rear probably has an integrated magnet. I found the rear with the magnet much harder to find in the US as a retail product.

Also, when it comes to centerlock, there are two types of locking nut which is indicated on Shimano packaging. One has the tool engage internally and the other externally (the threads are the same). Shimano rotors seem to come with the nut, but you could reuse what you already have. For me my Trek has the internal style front and rear, but the new rotor came with internal for the front and external for the back. The important thing here is that you have the right tool for whichever you have or choose to use, and you probably won't have the choice of which one comes with the new rotor.

View attachment 71845
Ok I’ll double check I guess , I asked trek in chat and they didn’t say center lock. I’ll chat with them again and screen shot the live chat
 
B4F64867-9C1D-4661-B7A1-781B8869DC75.png
9EE2E019-5DB4-4759-A654-96BB78790B80.png

So here’s the convo I had just now. They say 6 bolt and sent me the link too. I’ll call the trek store and tell them the exact model number rt-56 but it seems I ordered the correct pair. I asked about the speed sensor to the online chat and the online tech said it’s on the wheel. It’s definitely not on one of the spokes but I think it’s built in and tucked away differently than the 9.9s apparently.
 
You need rotors already? I turned over 5,100 miles on my Haibike Trekking. Still on the original pads and rotors. I might even want a new eBike before I need rotors. This one is 4 years old now.
 
You need rotors already? I turned over 5,100 miles on my Haibike Trekking. Still on the original pads and rotors. I might even want a new eBike before I need rotors. This one is 4 years old now.
No just ordering spares to have in my personal stock.
 
So here’s the convo I had just now. They say 6 bolt and sent me the link too. I’ll call the trek store and tell them the exact model number rt-56 but it seems I ordered the correct pair. I asked about the speed sensor to the online chat and the online tech said it’s on the wheel. It’s definitely not on one of the spokes but I think it’s built in and tucked away differently than the 9.9s apparently.
Here is a picture of Shimano SM-RT56M (180mm) rotor out of my spare parts shelf. It only takes resin brake pads (B01S). If you ordered SM-RT66 rotors you would need other brake pads!

No speed sensor is part of the rotor as the sensor is attached to the rotor by 2 screws, at least on my Specialized Vado 4.0.
HTH
 

Attachments

  • Shimano SM-RT56M.jpg
    Shimano SM-RT56M.jpg
    403.9 KB · Views: 387
Here are two photos of the rear rotor of my 9.9 You can see the magnet between two of the rivets on the inside facing the hub. On the other shot you can see the retaining nut (black with white "Shimano") that requires a special wrench Below is a link to the park tool version of that wrench:

View attachment 71861View attachment 71862
Going to order that park tool as well. I have no intention of changing the rotors myself when the time comes though.

What do you think of what trek live chat told me? Are they correct about the rotors for my 8s?
 
Here is a picture of Shimano SM-RT56M (180mm) rotor out of my spare parts shelf. It only takes resin brake pads (B01S). If you ordered SM-RT66 rotors you would need other brake pads!

No speed sensor is part of the rotor as the sensor is attached to the rotor by 2 screws, at least on my Specialized Vado 4.0.
HTH
My rotors say “ resin pads only”. I’m going to call the lbs tomorow to make sure they order the RT56. The live chat person types rt-56 but linked to rt-66. My original pads are the shimano B01S so I’m 99.9% certain it’s the RT-56.
 
Back