650b Wheelset for my Marin Gestalt - Questions

[tlarwa]

I'm considering the purchase of a 650b wheelset so I can run wider tires on my Marin Gestalt this winter. With the current 700mm wheelset the widest tire I can squeeze in is 38mm ... anything wider will rub on the seat tube (plenty of clearance otherwise). See my thread on this topic here: https://forums.thepaceline.net/showthread.php?t=225372&highlight=marin+gestalt
I'd like to be able to run a tire like the 47mm WTB Byway Road Plus, or something similar. From my calculations, assuming a sidewall height of 45mm or so on the WTB tire (a guess), the overall diameter of the 650b wheel/tire combo would be about 674mm, which is a bit smaller than the 688mm diameter on my current wheel (so there should be plenty of clearance at the seatpost). Is my thinking correct? I've never run 650b wheels on any bike before. Also, what inner rim width should I be looking for to work well with a 47mm tire like the WTB? I don't want to break the bank on these since they are only for winter riding on gravel. Any help, suggestions, confirmation of my thinking, etc. is appreciated. By the way, I need the wheels to be 142x12 TA rear, 100x15 TA front, with 6 bolt rotors and an XD driver.

Tom

[mattnes17]

Save the difficult calculations for the internet wizards. Have a look here:
http://www.bikecalc.com/wheel_size_math

The Byway is a wide tire. Id measure the minimum clearance between your chainstays and go from there. If there is 50+mm of clearance down there, you should be good to go.

For wheels, I'd go with Stans. They have tons of good quality stock builds on eBay that wont break the bank and last many miles. I can personally recommend the Arch for use with the Byway. It makes the byways BIG. To play it safe, Id go with the Crest rim, which is on fire sale on Stans site:
https://www.notubes.com/catalog/product/view/id/352384/s/crest-rims-revive/category/4/

[tlarwa]

Thanks for the calculator link ... good to see I was pretty close on my manual calcs. I'll have to verify my clearances, but I'm pretty sure I have about 50mm at the chainstays and 58mm or so at the fork (and that was with a 700 tire, not 650, so there should be even more space than that). The real issue was at the seat tube.

[Pelican]

FYI, my friend at Marin confirms it'll fit (AC wheels w/Byways).

[tlarwa]

FYI, my friend at Marin confirms it'll fit (AC wheels w/Byways).

Thanks, looking forwarded to getting them mounted up and on the bike!

[Jaybee]

FYI, my friend at Marin confirms it'll fit (AC wheels w/Byways).

Does your friend at Marin (who, btw, are killing it with their most recent stuff) know if the Cortina will fit the same tire/rim combo?

[yonderb0y]

WTB keeps a handy list of frames that fit their Road Plus tires (Byway & Horizon):

https://www.wtb.com/pages/road-plus/