hey gime a break
1. sno bikes aren't bikes or sleds. so you feel a little panic without a foot pedal to stand on cause you grew up on Honda 90's.........gotta get over it, you don't need a foot brake........ride some more you'll get there.
2. brake discs exposed to the snow build ice on the disc face and the ice circulating past the pads keeps pushing your pads back so when you grab the brake the first squeeze pushes the pad closer to the disc but maybe no enough to make contact and produce friction.......a little more panic.
all the sled manufactures that have experimented with this issue cover their disc and protect them from the snow and ice, and all the good sleds require just a little squeeze for full on pad contact. If your sled need more than half a pull, something's wrong. All the discs on the sled driveshaft in the tunnel made it one year before disappearing in a cloud of litigation...........tooo many paniced pilgrims making three squeezes while they hit road crossing at 80mph.
3. So on the sno bike you need to cover that disc or learn the 3 squeeze stop.
An ATV master cylinder with far more fluid displacement per squeeze can help.
Helped but didn't solve our poor braking on custom chute climbers with disc inside the tunnel. Soon as we moved the disc inboard where they were dry and hot, spot on instant braking.
4.the first sno bike I build I used sled brakes and a sno bike really doesn't need that much stopping power. The current popular bike kits are a little short pure braking power but adequate. My newest sled is just adequate also, I will however make a disc cover and experiment with bakes right now even if its a little weak. I have tried a road bike master cylinder on the small willwood caliper and you can make lock up now brakes on a MTN H........except for that nagging ice build up issue.