I’m what you’d call a ‘beginner’ when it comes to maintenance. I sort of enjoy it but I never get things right first time…

The photo below shows a 2005 5 Spot, Avid Juicy brake, Avid 185mm rotor and what suggests it is a 185mm adaptor. Why won’t the damn thing fit?

I now have a 203mm adaptor on there and it seems OK.

P1010320 by craigbart, on Flickr

my guess is its a 140mm IS mount not a 160mm IS mounts, only a guess though!

Which way is the arrow pointing?

it is 20mm smaller at the back than the front so
203 F 183 rear
180 Front 160 rear
hence why the 203 fits and the 185 does not

Is the adaptor on the wrong way round?

oh and that…

Adaptor is the wrong way round! Swap it round and it will work

Sorry – still don’t get it! Should the writing be on the inside? Its a rear adaptor and the arrow is pointing to the rear of the bike. whatever way around it still isn’t big enough to get the caliper off the rotor

will try again – other way around. Thanks all, in my defence, its been a long day

arrow might be pointing in direction of rotation..

adapter looks the wrong way round

I agre with Junkyard I think. On my bike I use the same size addaptor at the front as on the rear but the front is 185 and the rear 160. IIRC some adaptors are sold this way as well in that they are the same but for differnt sizes depending on where used.

The adapter is definitely on the wrong way round. The arrow should point upwards

all adapters are like that – 20 mm larger at the front than the rear as the IS tab is different front and rear relative to the hub centre point.

😀

The arrow points in the direction of rotation, not towards the rear of the bike.

Support your local bike shop

lol

Glad to have provided some amusement…

The 203mm adaptor is the only one that works – the 185mm is still too small – even when the “right” way around!

Sorted now, even if it doesn’t make sense (to me anyway).

its what i said the 203 will be front size and 185 the front size.
put it on the front see what happens

Junkyard – Member
its what i said the 203 will be front size and 185 the front size.
put it on the front see what happens

POSTED 27 SECONDS AGO #

Just confuse the lad why dont ya! 😉

He means a 203 front adapter becones a 185 when fitted to the rear.

I don’t get it… I’m upgrading my rotors soon and also have Avid Juicy brakes.. if I want a 180mm rear rotor what adaptor do I need? Currently on 160s.

I dont he had two adapters one is 185 one is 203 that is the front size rear is 20 mm less…i will take the vague and unclear bit though and yes it is not helpful due to my wording.
poster above most ones state the size or say F or R on them [ some hope say both sizes]. if you upgrade you need new adapters but you need to get different ones for the front and for the rear.
So you need 180 Front and a 180 rear which would give [160 rear or 203 front if swapped]
Hopefully clear now

Nope. And If he ends up doing an endo off a cliff we’ll know who to blame 😉

couldashoudawouda explains it well. Junkyard says the same thing (and thanks for the help btw) but needs to borrow a comma or two.

It really doesn’t help when CRC info states the following: –

http://www.chainreactioncycles.com/Models.aspx?ModelID=15259

“Avid mount adaptor to mount a 74mm post mount caliper (i.e. Avid, Hayes, etc) to a 51mm International Standard frame mount to accommodate a 185mm rotor.”

It doesn’t accommodate a 185mm rotor on the rear!!