How much clearance between the stays (both seat and chain) do your frames have?
I wanted to get a feel for "27.5+" compatibility, but whoever does the On One Facebook page just keeps telling me that "is designed for 29er wheels", which isn't particularly helpful.
It's tight with a 29" tyre and a 2.25 Smorgasboard.
Given the stay shapes by the BB I reckon you'd struggle.
Tight in terms of height or width? From pictures it looked like there is about 70mm where the metal plate is.
It'll depend where the widest point of the tyre will be I guess but the stays curve back in a bit after the 'flare' for tyre clearance by the BB.
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Edit although seat tube clearance is a bit tight too;
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Thanks, this is really helpful.
How much clearance are you getting either side of your 2.25" tyre? The widest point on a 27.5+ should be in roughly the same place.
Also, look at how tight those stays are. That photo should be marked NSFW!