Originally Posted by
iamabluelotus
How much clearance do you have between the heel and the pannier, and what are your pannier sizes?
I'm trying to work out if I can tour with my gravel bike, with chain stay = 425mm as well, and 175mm crank length
Ideally, you do not want your rear load to be too high or too far back, that can impair handling on the bike, so a longer chainstay is better. My heavy duty touring bike has 466mm chainstays, my medium duty touring bike has 450mm chainstays, my light touring bike has 445mm chainstays. I wish all of them were 466mm, but you get what the manufacturer decided was appropriate for the bike usage. In my case, I think the manufacturer of the light touring bike anticipated that the bike would be capable for touring, but prioritized steering responsiveness over load carrying capacity.
On the shorter end, my road bike has 430mm chainstays.
I have an early 1990s mountain bike I use for errands, that has 425mm chainstays, I use grocery store type panniers on it, but do not carry a real heavy load for long distances on this bike.
Distance between heel and pannier? Just barely enough. Each time I do a bike tour, if I switched bikes I have to adjust the hooks on the pannier to minimize heel clearance. But some extra clearance is a good idea in case you pack a pannier with something that bulges out a bit. My shoes are size 10.5 (USA) or 44-45 (Euro).
In your case, you would need panniers that can be adjusted fore and aft. Budget panniers often have hooks that are riveted to the pannier, not adjustable. A rack that has lower bars to mount the panniers a few inches lower would help a bit for handling. For touring, I use Racktime Addit rack on my light touring bike, Tubus Logo EVO on my medium or heavy duty touring bike. These racks have that lower bar.
Some gravel bikes put the lower rack mounts way up high above the axle, but lower is better, as long as you have adequate tire room between the tire and rack.