Fuel EXe Fuel Exe 8XT - Rotor upgrade RT66 to RT86? UPDATE - New rotors ordered

[DocUK]

Folks,

I have a Fuel Exe 8XT with Shimano M6120 calipers and RT66 6-bolt rotors 203mm, I'm thinking of swaping these out for RT86 rotors, appreciate it wont be a night a day upgrade but marginal gains and all that. My son also has the Fuel Exe 5 with Tektro 6-bolt rotors, some queries for you please:

1) I assume the swap from RT66 to RT86 6-bolt 203mm is simply a case of straight replacement and they are compatible?
2) Can I put my RT66 rotors onto my son's Exe 5 just because google tells me they are a slightly better rotor and they are in good condition.
3) The final and big question would be new pads for the RT86 rotors, resin or sintered and any recomendations as this is new territory for me? I assume I have resin pads installed from new but haven't had them out to check but assume they are.

I'm a mid level rider no pro stuff going on here lol, but I'm a red and black trail rider, no I don't feel any real comporomise on my current setup but having rode bikes with better brakes (Hope) there's a huge difference, yeah I know comparing my Shimano M6120 / RT66 to a Hope setup is night and day but just interested in my queries above and welcome feedback for this small upgrade.

Cheers

 

[DocUK]

Replying to myself lol,

Bit more research and the Shimano NO3A resin finned pads seem to be a good choice to pair up with the RT86 rotor, resin gives a better initial bite over sintered which for my trail riding seems the way to go?

I was looking at the absolute black graphene pads, price doesnt put me off if they were as good as they make out, seeing mixed reviews online regards them though and some saying wet weather performance not the greatest?

 

[Stihldog]

Replying to myself lol,

Bit more research and the Shimano NO3A resin finned pads seem to be a good choice to pair up with the RT86 rotor, resin gives a better initial bite over sintered which for my trail riding seems the way to go?

I was looking at the absolute black graphene pads, price doesnt put me off if they were as good as they make out, seeing mixed reviews online regards them though and some saying wet weather performance not the greatest?

Hmmm , never heard or tried graphene type pads before. Interesting.

I use Magura brake systems and there are 3 types of pads available in the OEM. Race, Preformance and Sport. (Metallic, mixture, and resin …respectively).

I’ve always used the Preformance but, just recently, I installed the resin type. I don’t expect these to last as long as the other two types … but they are quite. The Preformance pads were only noisy for a moment when I rode through a puddle or got them wet. The heat seems to evaporate any moisture fairly quickly.

I suppose rotor type plays a factor also (heat dissipation), as well as rotor thickness.

I’m probably going to experiment with some different pad material and manufacturers. Hopefully I can still stop.

 

[DocUK]

Hmmm , never heard or tried graphene type pads before. Interesting.

I use Magura brake systems and there are 3 types of pads available in the OEM. Race, Preformance and Sport. (Metallic, mixture, and resin …respectively).

I’ve always used the Preformance but, just recently, I installed the resin type. I don’t expect these to last as long as the other two types … but they are quite. The Preformance pads were only noisy for a moment when I rode through a puddle or got them wet. The heat seems to evaporate any moisture fairly quickly.

I suppose rotor type plays a factor also (heat dissipation), as well as rotor thickness.

I’m probably going to experiment with some different pad material and manufacturers. Hopefully I can still stop.

Yeah I was aware of the graphene pads, not sure if its gimmick or not and I cant seem to find any real in depth reviews of them online.

Been doing some more research and come across the Shimano MT905 discs, can get them online for £51, seems they are a decent step up from the RT86's so thinking may as well look at those for biggest improvement for a rotor change only, and then the N03A finned resin pads to go with them.

 

[Stihldog]

Yeah I was aware of the graphene pads, not sure if its gimmick or not and I cant seem to find any real in depth reviews of them online.

Been doing some more research and come across the Shimano MT905 discs, can get them online for £51, seems they are a decent step up from the RT86's so thinking may as well look at those for biggest improvement for a rotor change only, and then the N03A finned resin pads to go with them.

Earlier, I tried the Shimano ICE rotors. Those seemed fine but I did have a complete rear brake failure (likely my fault on a long descent).

The Shimano master cylinder seemed fragile …I broke two of them.

I eventually went with MT7s. 220 front and 203 rear. I also allowed the brake lever to spin on the bar with a bit of hand force.

 

[DocUK]

Earlier, I tried the Shimano ICE rotors. Those seemed fine but I did have a complete rear brake failure (likely my fault on a long descent).

The Shimano master cylinder seemed fragile …I broke two of them.

I eventually went with MT7s. 220 front and 203 rear. I also allowed the brake lever to spin on the bar with a bit of hand force.

So I'm just back from my LBS, was picking up a seat clamp for my son.

Spoke about the Shimano MT905's and the owner, who is an experienced biker, wasn't too keen based on the 3-layer aluminium / stainless construction and feedback he'd had on them.

He recomended the Hope floating disc, same technolgy as many performance bike brakes so can definitely see the reasoning for the cross over into MTB rotors.

Now looking at them as my 3rd option lol

 

[skizzian]

thinking from a different angle (cheaper) I went to bigger thicker rotors
(came from Saints on my old bike) now running the M6120 that came with my bike
I've gone to 223 2mm thick Galfer on the front, and 203 2mm thick Galfer on the back
with cheap pads - Disco Brakes ceramic fibre
I run sintered on the back in the winter

they work really well - haven't done any multi hour Alpine descents, but it seems the big lump of Disc takes the heat fine

 

[Yobbo]

My Fuel+ came as standard with the 200mm RT86 lightweight discs and the Shimano finned pad with the XT caliper. I wasn't entirely happy with them. On the very steepest of descents I never felt entirely in control and coming to an absolute stop could be tricky when they were warm. I did a back to back comparison with my brothers Fuel exe which has SRAM HS2 200mm Discs and SRAM code R brakes and his were noticeably much much better at the front, but the rear was about the same. I am just a general rider and not doing competition, but the Fuel plus brakes didn't seem quite good enough even for a few local steep descents.

I made a simple change and binned the front Shimano finned pads and swapped them for Sintered Green pads. A total transformation. Now the fronts stop great and importantly feel the same as my brothers bike. I can now also lock the front wheel if I pull the lever hard, which was something I could never do with the standard Shimano finned XT pads.

 

[bmwpowere36m3]

I would say no... the RT66 is the SLX level rotor and the older ones were nice laser cut made in Japan. The newer ones are stamped from China. The RT86 is the Ice-Tech XT-level rotor, which folks have reported get out of "true" easier.

The difference, marginal, is going to happen when you heat-soaking the rotor on a very long, steep descent. The Ice-Tech will shed heat quicker, but also tends to warp easier. I would say, unless your trails meet that criteria (steep/long) or you have felt brake fad, then there's no difference in braking performance for riding "most" folks do (besides bike park).

I've run both, and very noticed a difference on my shorter travel bikes. Went from SLX (RT66) to XT (RT86) to Galfer Wave... all in the 1.8 mm variety. Now on my long travel enduro, I run the CL MT800 Ice-Tech rotors in 203 mm F/R with Shimano metallic finned pads.

On my eMTB (160/170 mm), I ran SRAM centerline with Code Rs prior and now Maven base with HS2 (2 mm) rotors. With Codes and centerlines I would get some fade after a few repeated DH runs. Now with Mavens and thicker HS2 rotors, zero fade so far.

I would look into metallic pads if you aren't running them already, that'll increase your stopping power compared to resin. Finned Shimano pads aren't really necessary (N04C), again less riding the extremes. The regular metallic work great (D02S). Otherwise go for larger rotor diameter, 200/203 to 220. Those will provide a much bigger impact on performance than ice-tech or not.

 

[Montana St Alum]

Folks,

I have a Fuel Exe 8XT with Shimano M6120 calipers and RT66 6-bolt rotors 203mm, I'm thinking of swaping these out for RT86 rotors, appreciate it wont be a night a day upgrade but marginal gains and all that. My son also has the Fuel Exe 5 with Tektro 6-bolt rotors, some queries for you please:

1) I assume the swap from RT66 to RT86 6-bolt 203mm is simply a case of straight replacement and they are compatible?
2) Can I put my RT66 rotors onto my son's Exe 5 just because google tells me they are a slightly better rotor and they are in good condition.
3) The final and big question would be new pads for the RT86 rotors, resin or sintered and any recomendations as this is new territory for me? I assume I have resin pads installed from new but haven't had them out to check but assume they are.

I'm a mid level rider no pro stuff going on here lol, but I'm a red and black trail rider, no I don't feel any real comporomise on my current setup but having rode bikes with better brakes (Hope) there's a huge difference, yeah I know comparing my Shimano M6120 / RT66 to a Hope setup is night and day but just interested in my queries above and welcome feedback for this small upgrade.

Cheers

1. Yes
2. Yes
3. It's personal preference. Resin is quieter, with somewhat smoother modulation, better for dry conditions.
Sintered more of an "on/off" bite/feel. Better in wet conditions. Last longer.
Regardless, if I put on new rotors, I generally put on new pads to bed them in together.

I doubt you'll feel much difference, but if you do long high-speed descents, the RT-86 rotors are designed to handle heat dissipation more efficiently. But if they get REALLY hot, they are more prone to warping. I've seen that on my son's bike.

 

[JP-NZ]

Ive got MT905's on my Rail and had the XT RT86's previously. The 905's are better but only by minimal margins. They get less brake fade on really long descents which is what the extra cooling fins on the rotors are for.

 

[DocUK]

I would say no... the RT66 is the SLX level rotor and the older ones were nice laser cut made in Japan. The newer ones are stamped from China. The RT86 is the Ice-Tech XT-level rotor, which folks have reported get out of "true" easier.

The difference, marginal, is going to happen when you heat-soaking the rotor on a very long, steep descent. The Ice-Tech will shed heat quicker, but also tends to warp easier. I would say, unless your trails meet that criteria (steep/long) or you have felt brake fad, then there's no difference in braking performance for riding "most" folks do (besides bike park).

I've run both, and very noticed a difference on my shorter travel bikes. Went from SLX (RT66) to XT (RT86) to Galfer Wave... all in the 1.8 mm variety. Now on my long travel enduro, I run the CL MT800 Ice-Tech rotors in 203 mm F/R with Shimano metallic finned pads.

On my eMTB (160/170 mm), I ran SRAM centerline with Code Rs prior and now Maven base with HS2 (2 mm) rotors. With Codes and centerlines I would get some fade after a few repeated DH runs. Now with Mavens and thicker HS2 rotors, zero fade so far.

I would look into metallic pads if you aren't running them already, that'll increase your stopping power compared to resin. Finned Shimano pads aren't really necessary (N04C), again less riding the extremes. The regular metallic work great (D02S). Otherwise go for larger rotor diameter, 200/203 to 220. Those will provide a much bigger impact on performance than ice-tech or not.

I’d say this ties in with what my lbs said about the ice rotors, basically said they can turn to butter and allegedly it’s down to the sandwich construction.

I haven’t actually checked my pads but fairly certain they’ll be resin, think sintered is the way to go from what I’m hearing, will take a look at them and may or may not consider hope floating discs just because

 

[DocUK]

1. Yes
2. Yes
3. It's personal preference. Resin is quieter, with somewhat smoother modulation, better for dry conditions.
Sintered more of an "on/off" bite/feel. Better in wet conditions. Last longer.
Regardless, if I put on new rotors, I generally put on new pads to bed them in together.

I doubt you'll feel much difference, but if you do long high-speed descents, the RT-86 rotors are designed to handle heat dissipation more efficiently. But if they get REALLY hot, they are more prone to warping. I've seen that on my son's bike.

Thanks buddy, seems the RT86’s aren’t the way to go. I’m certainly no prolific rider but I do get into the red and black trials and rides out are anywhere 2-4 hours of trail riding.

 

[DocUK]

Ive got MT905's on my Rail and had the XT RT86's previously. The 905's are better but only by minimal margins. They get less brake fade on really long descents which is what the extra cooling fins on the rotors are for.

Thanks mate food for thought. I’ve done around 300 miles since I got the bike last year, think I’ll put something in place at some point over the summer so I can see how it feels before the autumn kicks in

 

[DocUK]

Update on this, after a few weeks deliberating and research I've pulled the trigger on some new rotors.

As per the post I'm happy with the M6120 calipers, I mean I'd love to go to Hope's but that's obviously a pricey upgrade, so I just wanted the best upgrade I could on the rotors and pads. Thought to myself if I'm going to go from a £15 RT66 rotor to higher end I may as well push for a few more £ to the best I can get so have opted for the relatively new Galfer Shark Evo floating rotors.

Ordered placed and will get them installed in the coming weeks. For pads I'm going to go with the Galfer purple E-Bike pads as these seem to get good reviews, Pro's are better but allegedly a lot faster wearing.

Once installed and ridden on I'll post back my thoughts on the change.