Solid Rear Disk Rotor

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jth
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Solid Rear Disk Rotor

Post by jth »

Where can I get one?
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Slick_Nick
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Post by Slick_Nick »

Why would you want one? I heard it needs the slots to help evecuate water/mud that gets in betweehn the rotor and pad, or you'll have no brake.
'00 KDX 220R
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Julien D
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Post by Julien D »

Lots of people prefer solid rotors. Supposedly increased pad life, and better braking in wet and muddy conditions. With a slotted or drilled rotor, mud and pieces of rock and such actually fill up the holes. Ever take a look at your stock rotor when you're riding in the muck? Every one of the holes gets caked up with stuff.

I know stealthy offroad has them for the KDX, but they're the only ones I've seen. Of course, I haven't really been shopping for one. I'm sure there are others. Moose maybe? Check FRP?
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kdxmaniac
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Post by kdxmaniac »

if im not mistaking, a solid disk isnt good with heat. they warp.....those little slots help cool the rotor.
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96 XR400R
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85 goldwing 1200
02 BIG DOG PITBULL

gone but not forgotten
96 kdx 200
98 ktm 380 "because it dang near killed me!"
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Julien D
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Post by Julien D »

>|<>QBB<
kdxmaniac wrote:if im not mistaking, a solid disk isnt good with heat. they warp.....those little slots help cool the rotor.
Yeah, that's the argument against them. Another one of those things where guys that run them swear by them, and guys that don't swear they suck. Who to believe? I haven't tried one personally, but if you think about it in very simple terms, it makes sense. Mud and grit packed into the holes of the slotted rotor will probably create and hold just as much heat as a solid rotor would. So for dry and groomed conditions (mx track), you will probably see less heat from a slotted rotor if it stays clean, but in the mud and muck in the woods, does this also hold true? I doubt it.

Anyway, many of the better hairscramble and enduro guys around here run only solid rotors. I've been thinking of trying one. Tired of blowing through brake pads constantly.
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kdxmaniac
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Post by kdxmaniac »

i have never run a solid rotor...........so im just saying what i have heard. i guess the solid rotor would work better for mud.
my bikes
-------------
96 ktm 300
96 XR400R
07 hayabusa
77 kz 1000
85 goldwing 1200
02 BIG DOG PITBULL

gone but not forgotten
96 kdx 200
98 ktm 380 "because it dang near killed me!"
97 ktm 360
96 ktm 250
93 wr 250
94 dr 350s
93 kx 250
07 gsxr 1000
99 bandit 1200
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Post by gregp »

I have run solid rotors. I even made my own once. No big deal either way. If I were riding in mud *all the time* I would go out of my way to get one. Since I don't, I won't.
I never had problems with them overheating or warping. I wouldn't want one on a high speed street bike, though, as I am sure that this would become an issue with severe use.
Pads seemed to last a little bit longer, but nothing drastic, given the varied conditions they were subjected to.
Juliend is correct, the theory is that the mud gets wedged into those cooling slots, and it grinds away at your pads.
2004 Dual Sported KDX200
1999 Ninja 250 (Daughter's)
1996 DR 650 (stock, mostly street use)
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kdxmaniac
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Post by kdxmaniac »

as for riding in the mud, i dont really worry about my brake pads wearing out as much as all the bearings and seals that the mud is grinding away at. thats why i avoid mud if i can.
my bikes
-------------
96 ktm 300
96 XR400R
07 hayabusa
77 kz 1000
85 goldwing 1200
02 BIG DOG PITBULL

gone but not forgotten
96 kdx 200
98 ktm 380 "because it dang near killed me!"
97 ktm 360
96 ktm 250
93 wr 250
94 dr 350s
93 kx 250
07 gsxr 1000
99 bandit 1200
jth
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Post by jth »

Stealthy Offroad has Solid Rear Disk Rotors for 1989-1994 models on close out. I need one for a 2004 and all the part numbers I have checked indicate there is a difference. Can anyone confirm this?

I called FRP and Jeff answered. He said he would have to check if he had some but was in the shop at the moment (I could hear air tools in the background). I told him to carry on, I’ll call back tomorrow.

So my search continues.

If you go to the FRP Webb site and view Jeff’s tire change video, you’ll see he’s using a solid disk.

Thanks juliend
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Post by KDXsg »

I have put on the stock h series rear rotor onto my 92 e series . they are interchangeble. mine got the 6 x 8mm bolts. the part number may be different becos of sometime the rotor design but not different on the fit.
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Post by Julien D »

Yeah, I think you can use an E series rotor on your H with no problem. I'd like to try one myself. If I tried to avoid mud, I'd never get to ride!
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Post by kdxquebec »

I run front and rear solid rotors on my KDX. A friend of mine made them for me. Laser cut , hardened steel or some kind of stainless I believe. Can't remember. I like the advantages of solid rotors.
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Post by jad628 »

Strange how the better performing rotors on a car seem to be drilled and/or slotted. They dissipate built up gases better, allowing a better and more even pad contact on the rotor with less pressure...or so they say. The disadvantage of them on a car is that they can't be turned to true.

I'm not sure the attributes mentioned on a car carry over to a dirt bike, but then again S&D rotors on a car are usually more expensive than plain (solid) rotors, yet the solids on a dirt bike are MORE expensive than their slotted counterpart....go figure.

To me, the mud/grit/dirt on the leading edge of a pad would likely cause the most abrasion, while the slots would probably cake up momentarily, then purge in rotation. The sintered type pad would not "purge" as easily, so if you ran those on solid rotors, wouldn't the supposed cleaner surface advantage of the solid rotor be moot?

I'm definitely no expert, but I would bet that any performance advantage of a solid rotor is much less than the "it looks cool" factor that us guys are susceptible to. The price scares me off.
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Post by jth »

OK, I got the solid rotor from stealthy offroad for the 1989-1994 models (the only ones they had). It DOES NOT FIT. The bolts and bolt holes are very different.

The 1989-1994 models use a 6x14 size with a tapered cut like the sprocket bolts. My 2004 uses 8x15 size with a special ridge machined on the bolt and matching ridge machined into the rotor (sorry, a picture would really help here).

I'll meet up with a machinist friend this weekend to discus the better way to fix/adapt (and get some pictures). Should not be a big deal.
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