Mountain Biking - Should I simply order a 6" rotor?

I bought an Avid Juicy 5 203mm front brake kit in Hungary. Anyway, as I lately discovered, apparently, not only does the wheelset have to be strong to take the braking forces but the fork too. I have an RST fork. If it's gonna snap or become useless because of the 8" rotor then I'd rather pay those 25 euros for a 6" Avid Polygonal rotor. Every euro counts here, mind you, but if I have to spend 25 euros for a smaller rotor to save my fork from becoming useless and having to pay hundreds of euros then I will.

So: will my RST fork take the forces of an 8" rotor? Should I just order a 6" rotor along with the wheelset and wait until I get a serious fork before putting the 8" rotor on? Oh and what happens if I put a 2.2" tire on a Sun Double Track rim?

Thanks a lot for your patience,
-Drunken Chicken

2.2 on a Sun doubletrack is nothing... heck a 3.0 would probably even work. As for the rotor, I don't know.

2.2 on a Sun doubletrack is nothing... heck a 3.0 would probably even work. As for the rotor, I don't know.
I meant if the 2.2s aren't too small for the rims? Thanks anyway. :)

I think the 2.2's will fit fine, as for the rotor, I would probably go ahead and get one, unless you want to upgrade that fork soon. I'm no definitive expert on the situation though, so I would see what some others say too, I just know that regular disc brakes (6") create a lot of force already, so 8" definitely have the possibility of messing up something. Running 8" rotors voids warranties on some stuff, so you might want to check on that kind of stuff too.

I think the 2.2's will fit fine, as for the rotor, I would probably go ahead and get one, unless you want to upgrade that fork soon. I'm no definitive expert on the situation though, so I would see what some others say too, I just know that regular disc brakes (6") create a lot of force already, so 8" definitely have the possibility of messing up something. Running 8" rotors voids warranties on some stuff, so you might want to check on that kind of stuff too.
Well, if we take an extremely positive, optimistic attitude, 9 months at the least until a new fork. :p Thanks for the info! I suppose I'll drop those 29 euros for a 6" rotor. When I get a new fork I'll mount the 8" up front and keep the 6" one as a spare. :)

Hello DC, it's DA again, I think if your fork did break it would at the disc tabs where your caliper mounts to it. You shouldn't get into a bad crash unless your caliper goes into the spokes. I also think depending on your weight and what style of riding you do will decide how your RST holds up. I think you should also be saving for a better fork. RSTs come on Hardrocks so they can sell the entire bike at a very affordable price point. As you know, my Hardrock friends upgraded their forks....and that would definately eliminate any anxiety you might have about fork failure if you spend some money on a better fork. It will also enhance the performance of your bike!

Hello DC, it's DA again, I think if your fork did break it would at the disc tabs where your caliper mounts to it. You shouldn't get into a bad crash unless your caliper goes into the spokes. I also think depending on your weight and what style of riding you do will decide how your RST holds up. I think you should also be saving for a better fork. RSTs come on Hardrocks so they can sell the entire bike at a very affordable price point. As you know, my Hardrock friends upgraded their forks....and that would definately eliminate any anxiety you might have about fork failure if you spend some money on a better fork. It will also enhance the performance of your bike!
Yeah, the order of my upgrades is: Wheelset (very soon), putting front disc brake on (very soon, 6" rotor), rear disc brake (Christmas?) and then a fork sometime next year and last but by no means least, a new frame.
I wish they had that Manitou Sherman Flick Plus deal all year around (280 dollars), it'd come in very handy. :D

PS: Weight, around 100lbs (light) and I do all sorts of dumb things on my bike ;), freeride, downhill (after the 8th run on a proper DH track with lifts and everything, my brakes smelt of burning and my pads were glazed :D), dirtjump, anything really. The RST is holding up not-so-well. :p

Well, if we take an extremely positive, optimistic attitude, 9 months at the least until a new fork. :p Thanks for the info! I suppose I'll drop those 29 euros for a 6" rotor. When I get a new fork I'll mount the 8" up front and keep the 6" one as a spare. :)
Don't forget you'll need an adapter for a 6" rotor as well

Get the 6" then after the new fork and when you're ready to put discs on the back, you can have the 8" up front and the 6" on the back.

For 29 euros, you're not going to waste your money.

Don't forget you'll need an adapter for a 6" rotor as well
O_O Now THAT'S something new... I didn't know, thanks for the warning!

EDIT: Great, an adapter is 10 euros. :(
EDIT2: I need an adapter because they've made the Juicy 5 compatible to Manitou forks without an adapter and all the other normal forks need an adapter? I don't see the logic behind it all.

Ya, there's nothing like buying some brakes and forgetting to buy the proper adapter too. Of course, some brands sell the adapter with the caliper.

O_O Now THAT'S something new... I didn't know, thanks for the warning!

EDIT: Great, an adapter is 10 euros. :(
EDIT2: I need an adapter because they've made the Juicy 5 compatible to Manitou forks without an adapter and all the other normal forks need an adapter? I don't see the logic behind it all.Because it's easier to machine a post mount caliper (like a Manipoo) and adapt it to the other style rather than do it the other way.

Because it's easier to machine a post mount caliper (like a Manipoo) and adapt it to the other style rather than do it the other way.
Ah, I understand. Thanks, it would have been a too expensive mistake if you hadn't brought my attention to it. :)