BTW, you said you are trying to figure out what snack to bring on the ride. What did you bring when you bonked? To be honest, when I'm in ketosis and keeping my carbs below 20g, I dont' need anything at all on a ride, other than water (maybe some sugarless electrolytes). Are you sure you're in ketosis? If you're not quite there yet, you may still be using glucose as a primary fuel source and that will bonk you also.

Look for the signs that you're making and burning ketones. Do you have a metallic taste in your mouth? Are you peeing like a racehorse? Do you feel like you have an excess of energy? Mentally clear? less hungry, no desire for sweets or intrusive thought of food?

Goog