Fitting a larger rotor

buddy_club

My dad's bike is has a 160mm disc on the front, and as he is a big guy wants to put a larger one on, is it as simple as just fitting a larger disc? Surely i would need an adapter or spacer of some sort for the front brake to actually fit properly?
The fork is a SR Suntour Raidon x1

gt-arrowhead

Yep,you need the appropriate adapter for the rotor.

You need to get A) the correct size and the correct type.

The Raidon X1 is a post mount type, so you will need a post mount adapter.

gt-arrowhead

This looks a good link. Cant go wrong with Shimano. It has the options on there for you to choose the right size (im assuming either 180mm or 203mm?)

And it also shows you how to fit it.

http://www.ebay.co.uk/itm/Shimano-Disc- ... 1c21b03186

buddy_club

Cheers, gonna go for the 180, and you saved me ringing halfords up to get the wrong answer about the fork

Chunkers1980

Stick to 180mm max

gt-arrowhead

No worries Just to be 110%, If your mounts look like the one in this link, its a post mount.

http://aplbike.com/WebRoot/StoreES/Shop ... V32438.JPG

Chunkers, why would 180mm be max? I use a 203mm and i think its really good, doesnt flip you over the bars without warning, even with completely fresh pads.

I would say 180mm max for the back for sure though.

cooldad

Because the forks were not designed for 203, probably 185 max. So they will snap, and his dad will die, and he will cry.

You don't want that on your conscience.

What you use is up to you.

Chunkers1980

To be sure the fork is strong enough. Even if it is, it is over kill.

gt-arrowhead

I didn't know forks were designed with a maximum rotor size in mind.

I wasn't actually recommending him to use 203 by the way.

Cqc

I'm 8 stone and my bike came with 203/180 mm rotors, they feel great, all other brakes feel weak in comparison, be warned that when your dad goes for bigger rotors, he will never want to go back

gt-arrowhead

Cqc wrote:

I'm 8 stone and my bike came with 203/180 mm rotors, they feel great, all other brakes feel weak in comparison, be warned that when your dad goes for bigger rotors, he will never want to go back

+1

Kowalski675

Except after his forks snap 'cos they weren't designed for a 203mm rotor and he dies, as previously pointed out

Max disc size 185mm:

http://www.srsuntour-cycling.com/home/b ... ks/?Model="Raidon"

supersonic

All this never go back stuff is mostly just rubbish. Maybe if they weren't to your liking to start. But they can get too grabby.

gt-arrowhead

Ive only over used 180 rear 203 front, and i dont get the grabby feeling at all. I dont think i would prefer
a smaller front rotor. But i definitely wouldnt be bothered by it.

The only thing that bothers me with my brakes is that i get a "nothing then everything" feeling from the brakes when the pads wear a bit, and it becomes a bit more difficult to judge how much brake to use.

Kowalski675

I think you just contradicted yourself a bit there, lol.

The Rookie

GT-Arrowhead wrote:

Ive only over used 180 rear 203 front, and i dont get the grabby feeling at all.

Yes but you have Auriga's, now try them with decent brakes......

I ride 160/160, as I can stand it on it's front wheel one fingered and I don't do long decents, then I am happy with that.

poah

Chunkers1980 wrote:

To be sure the fork is strong enough. Even if it is, it is over kill.

most suntour forks are only warrantied for 185mm discs maximum including the raidion.

Chunkers1980

What does my statement have to do with what you have said? Which you've repeated from the info already given above?

gt-arrowhead

Kowalski675 wrote:

I think you just contradicted yourself a bit there, lol.

Thats not grabbing i was talking about. I was talking about the fact that it gets harder to modulate once the pads are worn to a certain point, as pulling the lever does nothing for a short distance.

The Rookie wrote:

GT-Arrowhead wrote:

Ive only over used 180 rear 203 front, and i dont get the grabby feeling at all.

Yes but you have Auriga's, now try them with decent brakes......

I ride 160/160, as I can stand it on it's front wheel one fingered and I don't do long decents, then I am happy with that.

I wouldnt say that Aurigas arent decent brakes (maybe are rubbish to someone who rides SLX brakes and other good brakes) , but i know what you mean about trying them with better brakes. Thats fair enough.

pesky_jones

Could it really snap a fork? Seriously?

Cqc

Their not grabby at all, they just stop when you want to stop, there's no 'will I stop in time?' feeling because you know you can

Kowalski675

GT-Arrowhead wrote:

Kowalski675 wrote:

I think you just contradicted yourself a bit there, lol.

Thats not grabbing i was talking about. I was talking about the fact that it gets harder to modulate once the pads are worn to a certain point, as pulling the lever does nothing for a short distance.

Eh? Aurigas are hydraulics aren't they? Hydraulic brakes are self adjusting for pad wear - no matter how much your pads wear the pad surface is always the same distance from the face of the disc.

gt-arrowhead

Yeah they are. And yes thats what i thought. They dont do that for some reason. Or maybe they do, but just to a certain point. I dont know why.

buddy_club

Dont reeeeeeeeally want a dead dad on my hands....

Kowalski675

GT-Arrowhead wrote:

They dont do that for some reason.

They do, unnless your pistons are sticking and the caliper needs stripping and servicing.

Kowalski675

buddy_club wrote:

Dont reeeeeeeeally want a dead dad on my hands....

Inheritence not big enough yet?

buddy_club

Na