Prius Prime Winter Wheels - Which size to use?

I've posted a link to this in the past: Here's a good chart showing rim width to tire size
Tire Width for a Wheel/Rim Size Chart

Yes, a 6" wide rim will hold a 195 tire just fine. For the prime, a 195/65/15 tire is an exact fit.

 

Interesting, looked up in Owner's Manuals:

2010 and 2016 Prius stock tire: 195/65R15

2010 stock rim: 15 x 6 J
2016 stock rim: 15 x 6 1/2 J

 

From Gen III to Gen IV changes even the offset, ET 45 the Gen III vs ET 40 the Gen IV / Prime.

 

If the rim is 1/2" wider, and the offset is 5 mm less, maybe that's to keep the centre of the rim more-or-less the same? My brain is full.

 

I have not received my Prime yet (still in delivery process), but can anyone confirm if it comes with standard All-Season tires?

If so, how is the performance in the winter for those all seasons? I know winter tires are better, but can you get by with just the all seasons?

 

A larger rim width will not shift the center line, just make the edges of the rim further out from the center. A 6.5" rim has a width of 165mm so it is still narrower than the 195mm tire... BUT, because the rim is wider, the sidewall of the tire will flex out a little more and bring the tire a teeny bit closer to the fender. According to this page at tire-rack, a 1/2" larger rim will result a 0.2" (about 5mm) wider tire.
Tire Tech Information - Tire Specs Explained: Rim Width Range for Street / Highway Tires

The offset shifts the center line. A larger positive offset will shift the tire closer to the center of the car, a smaller offset will shift the tire further out. A 40mm offset will shift the tire 5mm further out from the center of the car than a 45mm offset. 5mm is coincidentally also about 0.2".

You need to be careful when changing offset and tire size to make sure the tires don't make contact with the fender or suspension AND that the rim doesn't make contact with the brake calipers. Many of us have used 205 or even 215 width tires on our Prii and they work just fine, There is plenty of clearance in the fender area for 5-10mm of shift or width

Here's a reference that indicates the Prime can accept rim offsets in the range of 33-53mm. The stock offset is 40mm so again, you have margin.
Toyota Prius Prime Wheel Bolt Pattern & Offset, Stock & Aftermarket Rims, Lug Pattern, All Rim Specs
If you go to TireRack and look for prius wheels, it will also show a variety of options in the range of 33-53mm offsets.
Wheels for 2017 Toyota Prius Prime Premium

So. My opinion...You are plenty safe using rims from an older Prius on the prime. A 6Jx15 ET45 rim with a 195/65/15 tire will be fine.

 

Thanks for that, a lot of info.

 

That question has an unknowable answer. In the Pacific Northwet the snow is usually not very cold & crisp which gives better traction. Relatively warm, wet snow is slicker. It all depends on how well those particular all-seasons grip on snow, frost, ice (there are wide variations in winter grip between brands & models of all season tires), how steep the hills are where you drive, how much snow we get this winter, your driving style, and luck (what stupid thing will some doofus driver do in front of you). I put on Michelin X-ice 3 winter tires before the first chance of snow or black ice on the road happens. The Toyo all seasons aren't even very good on clean wet pavement.

 

^ Your odds with the stock all-seasons are best the first winter. Even then your stopping distances are going to be a lot more though. But if cash is short and you just bought, the first winter might be considered the honeymoon.

Keep in mind, beside more aggressive tread, snow tires have softer rubber compound, that stays more pliant in cold temperatures.