revcp 

Greetings, all. I have a 2017 Rove AL on which I am replacing the wheelset in order to go tubeless and switch to 11 speed 105 from 8 speed Claris. Most wheels on the market, of course, are TA. I found a good deal on a DT wheelset (470db rims, Spesh SCS hubs). My question is about making an adapter work for the rear hub, as I read this online about the SCS rear hubs:

"What is SCS? It is 130mm spacing road disc through axle. Say it with me "130mm Road Disc Through Axle". It is NOT, I repeat, NOT, 135mm spacing disc. It just so happens to MEASURE 135mm end cap to end cap, and that is a horrible coincidence that I blame Specialized for. Why couldn't they have gone to 136mm or 134mm and avoided the number one confusion around SCS? 135mm spacing is what any regular old disc quick release hub is. 130mm spacing is what any regular old road rim brake quick release hub is (nowadays). When bikes went to through axle, they needed some way to keep the wheel centered and "retained" in the drop outs while you fished your axle through, unlike QR where the little skinny nubs stick into the drop out (and actually EXCEED 135mm if you were to measure, 135mm is face to face of the interior of the drop outs). So, bike companies created a 3.5mm recess in the inside face of the drop out, and extended the end caps 3.5mm per side. Net net is 135mm inside clear space (OLD - over locknut dimension) just like on a quick release bike, but now your hub measures 142mm. Voila, 12x142mm spacing is what any regular old disc through axle hub is."

So... anyone out there who can corroborate this? Is it not possible to get a QR adapter that will work for this rear hub? Or would one "kinda work" for fit, but leave the chainline a mess? Would love to get your opinions.

revcp 

I chatted online with Specialized. They confirmed that this rear hub will work only with frames it was originally made for, Diverge and Crux. I guess people were pissed, and rightly so, when they found out that wheels that worked with EVERYTHING else with a purported 142mm rear would not work with their frames.

msu2001la

Specialized used this design on disc road/CX/gravel bikes for a few years in the mid 2010's when road disc was still emerging, before the industry settled on 142mm TA as the road disc standard. Specialized has since changed both the Diverge and Crux to standard 142mm TA'S.

I think there are adapters that can be used on those Specialized frames that will allow more standard hubs to be used, but it's still a 135mm disc hub which is an odd size.

Polaris OBark

135mm disc hubs with quick release are completely standard (and equivalent to 142mm thru axle).

My guess is this must mean something else.

msu2001la

Here's a handy graphic:

revcp 

This is true. The problem is that the Specialized TA hub measured 135mm, not 142, so a QR adapter would take it to 128mm or thereabouts, so it would not fit in a 135mm QR dropout, the narrowest with disc brakes.

grolby

I would avoid SCS and just buy one of the many wheel sets that are available as either 135 QR or 142 TA. These hubs are essentially thru-axle but come with interchangeable end caps to accept either a standard quick release or a thru-axle. Hunt and HiFi wheels are sold this way; I imagine any other manufacturer using own-brand hubs manufactured by Formula or similar open-press manufacturer such as Boyd and etc will make use of the same system.

revcp 

I did indeed end up going with the Hunt Gravel 4-Season.

Elvo

Specialized also had the 142mm+ standard too which only worked with their frames