Some weak rear braking has made me look at them a bit more closely and it appears I have installed the rear the wrong way. Thanks for advice.

I’d be surprised if it made a difference

I tried both ways when I had squeaky brakes and nothing altered, feel, power, noise, talent 🙁

(are they original minis ?)

Yes, looks like the back is the wrong way around

Agree, rear is on wrong.

There is probably a small arrow etched into the rotor near the bolts, but as its on backwards its probably sitting against the hub.

what difference do you think it’ll make to braking though ?

(when were they last bled, might the pads be contaminated ?)

the part of the rotor spoke furthest from the centre should be leading

Got spare pads, will do a fresh bleed with old pads in, Isopropyl rotors and calipers and let dry and then put in new pads and find a hill. Reverse rear rotor. Thanks.

I ran my old Mini’s the “wrong” way round for years and it made no difference to the feel or power. The shop installed them originally and they were one of the very first sets available to buy so I just assumed the dhop knew what they were doing! It was only when I fitted new wheels a couple of years later I found the direction arrows on the rotors. Correct way is as shown in the front rotors in your pics.

It won’t make any difference on the bike, but the wrong way puts the spokes of the rotor under some tension rather than compression, so they’re more likely to fail.

spokes fail under tension do they ? 😯

+1 Paul, using lighter rotors backwards makes them more likely to fail – probably when you need them most! There are pics about of an Ashima failing this way.

pants – rotors are designed to work under compression, spokes are designed differently to work under tension. They’re not the same!

Nothing could possibly go wrong running a rotor the wrong way?

Especially when a manufacturer accidentally / stupidly prints the arrow pointing the wrong way. 😉 TBF – probably combined with light weight / thin rotors.

I’m referring to a recentish post on here about a manufacturing error for these rotors that had the same problem but I was possibly lucky.

Search on here for ashima face plant (and more photos elsewhere). I will try and resurrect the photos. Once these rotors were fitted the right way they seemed fine.

#Edit – photos:

god, those ashima things are made out of air !

I’d be astonished if Wally’s (now invisible) ones did the same

Most rotors have small arrows on them to point the right direction just like tyre`s 🙂

Correct Chris_mbuk. But!!!!
Ashima printed a batch the with it printed the wrong way round! 😯

I’ve got two from that batch and ran them the wrong way for a while until a mate pointed it out and I swapped ’em round. They’re still going and I’ve not died, yet 😉

They thought they were right, turns out they were wrong. Ashima’s science bit:

I have my tension/compression the wrong way around. (I ahd the braking force in the other direction for some reason!) They fail under compression because there’s nothing to stop the compression causing the spoke to bend sideways. I think they have to be very light and hot for it to be a major worry, but better to have them on right in the first place.

Have you changed your rear pads recently? The front disc on my hope mini’s is slightly dished from use and the new pads have taken an age to bed in, with poor braking levels while it’s been doing so. Really need some new discs!

Well having posted that I need new discs, I came across this thread to double check the direction for my christmas present rotors (not marked on five bolt hopes apparently) – thanks father christmas!