Here are the geo charts for my Thunder Comp and the Double Cross Disc.
Top tube delta is 51mm so I went with a 50mm shorter stem. This seems to be working really well but I’ve also noticed this is probably helped along by the fact that the bars are 5cm+ higher on the TC. They’re also 46cm wide whereas I usually ride a 38cm on my road bike. I think the additional width will be a huge help downhill and on the rough stuff. Narrower bars just don’t feel great off-road to me anymore.
I’m really happy with the bike and excited to race it on gravel but it’s obvious I’d be better on a medium. My testing over at the Cox building’s dirt walking trail showed a high propensity to washout the front wheel under aggressive cornering. I’m just too far back and can’t really do much to weight the front wheel more as my pedaling position is ideal. I’m going to experiment with braking and try to see if that helps. But really this is going to be a non issue for my racing as the corner is generally not where I’m having problems.