From what i can see, the evolution of the on one is (basicaly thus)

Inbred

456, inbred, with the head tube raised to allow for a longer fork while maintaining the head angle (and tougher built)

summer season: the 456 was too steep when run with a compressed fork, so the summer season was produced, which ended up being similar head angle under a 4″ fork, and slacker with a longer fork

my ROUGH guess calculations point me in the direction that a summer season with a 4″ fork, will be similar, if not the same as a regular inbred, only with a slightly lower BB, and tougher tubing?

the reason i ask is:

ive got a summer season, currently with a 4″ fork, and bodged single speed (as i didnt get on with a loooong fork)

if i swapped it for a slot dropout inbred, it would allow me to pure SS it, and it would be a smidgen lighter.

how else would it differ?

head angle would be my ‘guess’ – don’t they have the geometry on the OO site?

summer season: the 456 was too steep when run with a compressed fork, so the summer season was produced, which ended up being similar head angle under a 4″ fork, and slacker with a longer fork

Brant wanted a bike to ride down hills in Hebden Bridge and couldn’t be bothered working anything out too much, so ordered 100 frames with a 2deg slacker head angle than the standard 456.

He also ordered two 2deg slacker than that!

The 2deg slacker lets you either run a shorter fork for the same head angle, or the same length for a 2deg slacker one.

No more to it than that.

For a given length of fork, I seem to remember Inbreds and 456’s have the same head angle. But that might be wrong. It’s been 2yrs since I left.

cheers brant 🙂

i got my summer season as a budget HT DH bike, but have subsequently complemented it with a Patriot66.
summer season is now with a 100mm fork, but want to get something that i can swap out 700cc wheels and a rigid fork, and ride as a commuter/tourer.

hub gears too perhaps.

like a bike form of a mr potato head.

(im just looking at excuses to buy another frame tbh)

Ooo, its a toughy.

based on what brant said:

456 SS with 100mm fork is 69.5 deg
inbred with 100mm fork is 70.0 deg

not reaaaaallly worth the 150 quid ish for slot dropouts i dont think.

i prefer the colour of mine too….

OOOOO, rigid on one 26″ fork would accept a 29″ tyre.

69er options!

brant gave dirt magazine a 456 with a 29er Reba + tyre to test – iirc they really liked it.

based on using iphone anglefinder…

my summer season with 115 rebas is 66degrees
my slot dropout with 130 revs is 67ish (i think)

The summer season feels much slacker than this though. odd.

that’s cos the angle finder in your i-phone won’t be accurate OR precise…

(… or repeatable, or calibrated, or reproduceable, or … blah blah blah)

i know it isnt accurate, but gives some idea.
Although using the same device it should at least show the difference. and it gave the same reading on different days.

based on what it told me about my cross check, i would add 2 degrees to my measurements above…

based on what brant said:

456 SS with 100mm fork is 69.5 deg
inbred with 100mm fork is 70.0 deg

Surely based on what brant said there should be a 2deg difference, not a half deg difference? Or am I missing something…

Based purely on ride experience

Love my inbreds
Hated my 456
Hated a borrowed summer season

Plum

poppa: thats based on the measurements on the on one website too, they took the angles off the 456s with a 120mm fork, and off the inbred with a 100mm fork, so i lost the 2 degs in the 20mm difference there