Finally obtained Nokian Hakkapeliitta R3's

Had my new Nokian Hakkapeliitta R3's installed over the weekend. The biggest difference in driving feel over the factory Ecopias so far is in regen braking. It seems like the regen is only 50% of what it was on the original tires, and I am putting a whole lot of wear on the brakes out of necessity because the regen is lacking that much.

Does anyone know if the tire diameters can be altered in coding? Although there shouldn't be a huge diameter change between the original 175/60 and winter 155/70 tires, perhaps the regen system is that sensitive and changing the coded diameter may improve the feel.....

Back of the envelope, wouldn't the sidewalls be only 3.8mm taller? That would only increase the diameter of the wheel assembly around 7mm, and turning over that envelope and ciphering on the front that would make the overall circumference like 1% greater. I'd think that wear, inflation and manufacturing tolerances could make a bigger difference than that. I can't imagine the regen system thinking the car was traveling 50 when it was doing 50.5 would have any noticeable effect on its operation.

But inquiring minds want to know how much more secure is the winter driving on snow, ice, mix, etc? Thanks!

vreihen said:

Although there shouldn't be a huge diameter change between the original 175/60 and winter 155/70 tires, perhaps the regen system is that sensitive and changing the coded diameter may improve the feel.....

Click to expand...

Early Mega World BEV's with standard wheels had the same 155/60 tires on 5" wide wheels front and rear without reduced regen power, so something other than a different tire circumference must be causing the reduced regen power. Others have reported this phenomenon after mounting winter tires, so something is happening.

Regen power can be reduced when the battery pack temperature is low during cold winter weather or when the rear tires lose traction. Maybe new winter tires could lose traction during regenerative braking on dry pavement.

I noticed the same thing when I put these tires on. It made a huge difference. I had to retrain myself to let off the accelerator earlier... but most importantly I learned to let off all the way on approaching a stop instead of just part way. It took a lot longer for me to get comfortable with the regen than when I first drove an i3... which took me only about 1 minute : )

The tires say they are ultra low rolling resistance on them.... and they certainly are!

Edit: Art, these tires actually have better traction and a shorter stopping distance in coldish temperatures.. anything below 45 degrees, so I hear.

My 2014 BEV has Bridgestone Blizzak LM-500 and I do not feel much regen difference after I swapped them in January. The regen is about the same strength and I am still able to stop on a flat service like before without using resistive brake. The only thing I notice is there is a whining tire/road noise, at low speed (<35mph) which only occur with the set of winter tire. I used 19inch 175mm in the back during summer/spring/fall. I am in NJ,USA and the ave temp is around 35F.

Now that I have a dozen or so heat cycles on the new rubber, they seem to be working much better under regen braking. Still not quite up to matching the well-worn factory Ecopias, but almost back to my braking marks at most intersections now.....