Forum menu
Is there an easy way to add a spacer kit to a rear non-Boost wheel (ie 142mm) to fit a 148mm Boost frame but spacing centrally ie adding 3mm each side so no need to re-dish the wheel (for easy swaps between frames)?
I understand unlike the good old 135mm and newer 142mm which share the same ISO disc mount standard the newer 148mm has moved the rotor position.
How then is this affected exactly and what is needed spacer wise for the rotor mount in order to fit a 148mm frame without messing with the actual brake on the frame?
And how does this all tie in with the cassette position (although the vast majority of the time I'm SS so I can easily move the cog to fit)?
My understanding is the disc is in the same position relative to the dropout so the best solution is a 6mm longer end cap on the non drive side, a 6mm spacer for the disc and a redished wheel which will now be less dished.
What you want is a 3mm spacer each side and a 3mm spacer for the disc and no change to the dish. These are available for at least some hubs, what hubs do you have?
how does this all tie in with the cassette position
Ideally you'd be pushing the cassette all the way over and doing the re-dish, spacing the cassette in won't be the best for your chainline. Do you have a boost chainset?
Well slightly hypothetical as I'm looking at a frame and wheel purchase but unsure whether it will be 142 or 148 and quite likely to change again hence I want the flexibility to chop and change easily.
Would rather stick with regular Hope Pro 4 hubs too in 142 than the Boost specific models.
So has Boost effectively just kicked everything 6mm >>> to the right?
I bought a cheapish kit from ebay that was just two 3mm spacers that sit either side of hub and another to correctly position the rotor. It's a bit fiddly if you keep removing rear wheel (spacers can drop out) but otherwise works fine. Works with any hub as far as I can tell as long as you're not using a centerlock rotor. Chainline not ideal as said above.
I've also used the wolf tooth boostinator kit for a DT swiss hub, that required the wheel to be dished but it does work better and it's not too hard to dish a wheel.
So has Boost effectively just kicked everything 6mm >>> to the right?
No, on a boost hub it's spread the flanges. It's just bodging non boost hubs that becomes an exercise in shifting everything one way or the other.
Hope do a kit for their Pro2 Evo and Pro4 hubs, no dishing needed. I'd run a non boost chainring to keep the chainline sensible.
So has Boost effectively just kicked everything 6mm >>> to the right?
As above, it's spread the flanges, so moved the disc and cassette 3mm outboard each.
Option 1: you shift the hub 3mm to the right (6mm spacer on the left), space the disc by 6mm and re-dish.
Option 2: you can leave the hub centred (3mm spacer on each side) space the disc by 3mm, and bring the chainring in by 3mm, which you do by running a non-boost chainring setup. Of course, your frame may not have clearance for that last part.
I wouldn't want to run a boost chainline at the front with a non-boost chainline at the rear, as the "correct" chainline puts the front wide relative to the rear to start with. (The reverse - non-boost front, boost rear - should work well)
Thanks chaps - very helpful.
Hope 148 x 12mm Boost conversion kit for Hope Pro 4 and Pro 2 Evo hubs
Includes rotor spacers, end caps, longer rotor bolts and freehub spacer (not required on all hubs)
Instructions here: https://singletrackworld.com/forum/topic/converting-pro-2-rear-hub-to-boost/
I've used the 3mm spacers and disc spacer kit a few times now and never had any issue with chain line. 3mm can be adjusted for quite easily.