Best buy on ice tyres?

it's fun!! full studs for ice racing, enduro-type riding on iced trails, or general-purpose studded tires that can do pavement?

for the enduro work the local guys like the Trelleborg/Mitas Winter Friction pre-studded ones, or Best Grip screw-in studs. not sure what tire they use, I'd think certain desert/hardpack type tires for a denser knob pattern = more studs on the ground, and a stiffer compound which keeps the knobs better

for dual-sport I've had really good success with Mitas XT-644 with normal car studs. These can do pavement. Long stretches if desired. Grippy but long-lasting compound. Holds studs well. I had one stud per knob put in - mx shop and winter riding specialist shop snellingen.no make tires like this too - they put two studs per knob in the two center rows of knobs, one stud per knob in the rest. they also use some form of glue to better keep the studs. I did lose all of the rear center studs over time, glue would have helped there! they sort of twist out under power, studs went but there was still enough "knob meat" to hold them

did you see TomTom's tires in a recent post? these are full-on ice racing ones as I understood, around this post: http://husaberg.org/mechanical/19501-confirmation-570-seat-off-trick-5.html#post157316

... for frozen-lake duties, another way and probably the cheapest one is to take an mx tyre, can be somewhat used afaik, and screw in sheetrock or wood screws from the inside, then cut up an old inntertube and use as a liner to protect the innertube

note! these are sharp and dangerous!, as you can imagine - you really want a "dead man's switch' that kills the motor when you fall off

For ice the best is finndubb, just like in TomTom's picture.

I do however think a good pair of studded enduro tires are more fun on ice. IF they are made the right way, like the ones I have (monster Micke's), so the studs don't flex as much as on most enduro tires. Works just as fine under most ice/snow conditions.

Where and exactly what you should buy is difficult to say as "North" can be all the way from the Canadian west coast to the east of Sibir.

i had a set of trelleborg studded tires years ago, you lose a lot of skin mounting them.
if you could run the bike on it's side, you could saw down a tree

If you want to do everything well, trelleberg/mitas studded tires all the way. They can do half a meter of snow easily, grip well enough on ice and on small roads they work really well. They can also take a little pavement.
If mainly for pavement maybe short little studs. Ice spikes for 100% iceracing.