I'd say it's rider preference. I haven't owned a 146 for a long time but my 08 xp would almost want to wheelie all the time vs my 154 xp. I have my Gen4's setup to wheelie when I want not when the sled wants

Live fast or die last

 

Yup 146" is a wheelie monster.

154" is way more flat footed.

146" and 137" in the backcountry are my favorite choice.

154" is way to long and awkward and slow for what we want to do.

 

My brother can wheelie his 154 850 as good as anyone on a 146. Has gone over 1/3 of a mile. He definitely changes his setup a lot between the flatland and the mountains tho. We had 146's before but with the 850's we went to 154's. But we try to ride at least 3-4 trips out west a year and 146 trench too much.

 

The 146 is the new 121

The 154 is the new 137

fkin "wheelie pirates". haha

 

I don't have much experience of modern Ski-Doo's, but I do have recent experience of owning Lynx Boondockers with 146" as well as 154".

The 146" is definitely more happy to pop wheelies and this can be to your advantage as well as disadvantage. End of the day, it's just basic physics with less track behind the center of gravity and the forward driving force.

Then again, being prone to wheelies can be adjusted and the number one variable is definitely body position. Where is your footprint and how high / low / forward / rearward is your handlebar...? Center shock limiter strap length, rear shock compression damping and spring rate and the possibility to adjust rear-to-center coupling have a big impact too.