Can anyone give me an idea of what rigid fork a-c is needed to replace a 140-150mm 650b fork (suspension sag corrected)?
Unless I'm missing something (quite possibly) can you not measure the a-c length of the fork, take the sag off & that should give you the fork length you need?
Yeah of course!
That comes in at 495mm. Forks are in 160mm mode with an a-c of 550mm. So in 140mm mode they'd be 530mm. Then take off the sag 25% of 140mm = 35mm. So that gives 495mm
Plenty of options at 483mm, but I guess that's for 130mm 650b
I got some rigid boost Marin forks, 490mm a to c. Takes a 9mm axle. With front wheel
Any good
I'm looking for a 29er version at the moment, with 15×100 hub but can't see anything in my admittedly limited price range. I have even been looking at Chinese eBay specials , not a route I really want to take.
These are 500mm a-c boost - Whisky No9MTN
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Others fork options - but possible stock issues / overseas orders..
483 - https://www.pipedreamcycles.com/shop/crmo-forks/ Sirius Fork
490 - https://www.ison-distribution.com/english/product.php?part=FKMRC2900 MRP
483 - https://www.ison-distribution.com/english/product.php?part=FKSUKRLK
510 - RSD - US mail order
510 - Trek 1120 - Triton list these
490 - Carver - http://carverbikes.com/parts/forks/xc-490/
500 - Bombtrack - https://bombtrack.com/parts/forks/bps-fork/
for the forks shorter than you might need, you always adjust via lower headset, or just run 483 and see what it is like.
Exotic Carbon also do 490mm a-c forks.