My 125 does the same thing! Slow to turn over on cold weather. It helps to have the best cold cranking amp battery possible. Recommended Winter oil (10w-30) in motor. Good electrical connections from battery to starter.
I also do a couple things. The day before snow storm before I use the tractor, I put a small ceramic heater near it. I also have tractor on trickle charger only for colder weather.
I read/heard that you should use the recommended IH Hydrostatic oil in the tranny..... For one thing the this oil would suit better for winter startup than other brands oil that are comparable/compatible to the IH. Supposingly, with the IH oil, there is less strain turning over motor on cold start-ups. I'm not sure if that's true, but I'm guilty of being cheap!
