So I bought a used std inbred frame, but after riding it, I think it may be a 456 frame.
How do I tell the difference?
It seems some 456 frames don't have 456 decals.
The geometry seems virtually identical apart from seat tube/head tube angles, the only difference I can see is that 456 frames dont have V brake bosses and std inbreds have bosses on the seatstays to bolt on the removable alloy V brake mounts. Is this a reliable way to tell the difference?
this thread is useless without pics
Weigh it?
ideally frame only, no headset, seat qr, bb etc etc and clean
Pay no attention to what the stickers say - look at where the top-tube meets the seat tube and seat stays:
On an inbred, the top tube is slightly lower:
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On a 456, they line up:
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the top tube diameter on the 456 is the same size as the downtube. On the standard inbred, the top tube is smaller.
Ref bosses, my mk2 inbred has got welded on bosses, but my slightly more recent 456 has bolt on jobs. Just depends on the era.
A couple of years ago (3 maybe?) I bought a 456 new that came without a 456 sticker - just the Inbred ones - and it had bolt on V-brake mounts.
Between me and my brother we have a 7 year old, 2 year old, 1 year old and 1 month old inbred frames. The old one certainlly looks very skinny. The 2 year old and 1 are the same but the 1 month old frame has a fatter top tube from quick cursory glances.
Thanks duffer,
from your pics I sussed it and the frame is a 456 because top tube is same diameter as downtube i.e. 35mm. std inbred has smaller dia top tube.
thanks everyone.