Honestly but, maybe not attainable due to weight, I do not see any reason why the front wheels of the Aptera shouldn't be motorcycle style tires with a rounded profile and contact patch. With torque vectoring, traction control and hub motors, the ability to keep the rubber on the road should be fairly easy and provide a better ride.
As a motorcyclist with over 400,000 miles, I don't think mc tires would be suitable at all. They generally aren't built to carry the weight of an Aptera, and even if they could, they are not designed to take side loads. The sidewalls would be inadequate.
If this Aptera 3-wheeler is as popular as many of us suspect it will be, you will be comforted to know Aptera's embracing the 'right to repair' approach means someone will come up with a redesign of the front wheel skirts as an aftermarket product that will accommodate any tire/wheel combination that can work with the Elephe wheelmotor.
Depending on how good a driver Aptera attracts over time, including second and third owners, one might see a trend toward the forumla-1 esthetic of skirt-less wheels. Sure it will lower the range of the 1000 mile Aptera to 880 ... but the grocery store is only 4.6 miles away.
Heck, there is probably a way to use the friction and pressures on the tire that it would light up a strip embedded into the tire creating a light show on the tire.😎
But to answer the question, when you get yours you can put any size tire on it you want.
What would be cool would be for Roush to make tire suggestions, including suspension tuning advice based on the tire chosen and whether the principle being supported is speed, safety or comfort and/or on or off road or track. It would be particularly nice if they presented the objective data.
I don't think that will happen largely because nobody except Sandy Monro has figured out how to present this kind of objective engineering data for fun and profit.
Here in Sweden, based on available number of models, 195/55R16 seem to be by far the most common 195R16 dimension. I would just stick with that unless it's somehow way less efficient than a 195/45R16 tyre.
I just checked & my own car has 209 pounds per inch of sidewall, which is slightly better than Aptera, HOWEVER, Many other users with the same model have 1" bigger rims with 238Lb/in of sidewall, which is worse than Aptera, yet none of them have mentioned any issues.
I would like 195/50/R15. It is cheap and the choice is not bad.
1
Unknown member
Jun 22, 2021
I'll second this. I also want more rubber and a more compliant ride. Remember folks: with 3 wheels you WILL hit every pothole since you can't straddle them. 45% profile tires will pulverize your spines.
@Len With the wheel covers, you will probably need to keep close to the same wheel diameter. The Alpha wheel covers were very tight. Aptera also made special lightweight 17" wheels that fit the in-wheel motors. Maybe they will make the off-road wheel covers a bit bigger. Winter tires do work quite well on dirt, gravel, and smaller rocks, although they wear out quickly and don't work as well in mud as true off road tires. We run winter tires in the stock rallycross classes.
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Unknown member
Jun 24, 2021
Replying to
@Biff The Aptera is not a car. Not comparable. It will hit nearly every pothole and segment f rough road. No way to avoid it. Low profile tires are foolish. Especially in this application.
45 is a fairly standard profile these days. Base Tesla's come with a 45 profile tire and the performance versions have a 30 or 35 profiles. This is true even for the Telsa SUV's. Right now Aptera is running a Continental ProContact, which is a good all season tire.
22.9" is the overall diameter of the 195/45R16 standard size tires. 25.2 is a bit on the big side... Would need to be tested before I'll start buying tires in that size... In any case I'll be watching to see how things go for the first Aptera owners with this stuff as it develops further.
The other thing to remember is the Elaphe motors may not allow a smaller rim (Ie: 14" or 15" rim) so we might be stuck between a 16" rim and a tight wheel fairing. I would also like a little more meat in the tire, and just looking at the 195/45R16 tires there are very few options. Just a couple of highway tires, one snow tire, and no all terrain or hardened tires with additional belts or puncture protection...
Looks like there's a couple of comparable sizes that have several different snow tire options, but no all terrain options. Obviously efficiency is king, I'm just worried about rock punctures on an all season...
The argument for why it's ok is that the aptera doesn't weigh a lot so it will just "bounce" over potholes without damaging anything... I still want more rubber though, and three wheels means more weight per wheel than 4...
Just to clarify, I was addressing rim width, not diameter. For example, three 195/16R60 tires I looked at can tolerate a rim width range of 5.5 to 7" with all of them having a measured rim width of 6". The section widths were 7.9 to 8" and the overall diameter of the tires were uniformly 25.2". I anyone's curious, the maximum load was 1,279 lbs and would be lightly loaded on an Aptera. For those concerned about price, they ranged from $100 to $150.
We'll need to wait for a little more information before we have a good idea of what will work. I expect that Aptera's testing and subsequent tire choice will satisfy most. If they stay with a P195-series tire and you're looking for a comfortable ride, something in the range of 60 to 75 aspect ration may be to your liking (depending on the design rim width and the interior dimensions of the wheel covers). I'm content with staying tuned to Aptera's progress along with Roush's contribution
Snow tires work best with a larger sidewall, so it wasn't chosen for that reason. The tire size is constrained by the size of the in-wheel motors and the size of the wheel covers. The original wheel covers were tight even for a 195/45R16 and they are making them a bit larger for the beta prototypes. The tire diameter was probably also chosen to give their desired 110mph max speed for the max motor rpm while still working well at low rpm. Their is no transmission to adjust these numbers.
The Fiat 500 is the main mass market car using this tire size, so they will be common where the Fiat is popular and harder to find elsewhere.
Bruce is correct the P195/45R 16 was first announced, but they where assessing a slight large tire like a 205 or 215 at least in the rear tire for better pothole protection. All of which are common size 16 tires,
(I think I heard a 185 may have even been “in the mix, when assessing”???)
Remember these are development vehicles, alpha through delta to assess best choices for ultimate crash test to production
Back in the 50s / 60s the three wheeler BMW Isetta was nicknamed the "Schlagloch Suchmaschine" because no matter what, one wheel would hit the pothole. Hence I kind a like the back wheel to have air suspension .
@pilotmoss In the overall scope of tires profiles, a 45% ratio is about an average tire nowadays. It should give a blend of lateral wall stiffness and some ride comfort. It seems like an appropriate size since it does need to fit under the wheel spats and have a low enough wind resistance profile. I am hoping they have a nice sport all-season tire (300AA) for the car. Just to give you an idea of a "very low profile tire", my Mercedes S Class Coupe runs 295/30R20 in the rears. I did suffer some ride quality using these tires but needed the added traction of the sport tire and contact patch. But the low lateral wall height does not protect the rim as well and I did once sustain a wall damage when hitting a pothole.
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Unknown member
Jun 22, 2021
Replying to
@OceanDragon Contact patch size is strictly a function of tire pressure and axle weights via the equation Pressure = force/area. Solving for Area gives A = force/pressure. Sidewall heights, tire construction, and other factors have no effect on contact patch area. They can change the SHAPE of the contact patch, but not the area (size).
Honestly but, maybe not attainable due to weight, I do not see any reason why the front wheels of the Aptera shouldn't be motorcycle style tires with a rounded profile and contact patch. With torque vectoring, traction control and hub motors, the ability to keep the rubber on the road should be fairly easy and provide a better ride.
If this Aptera 3-wheeler is as popular as many of us suspect it will be, you will be comforted to know Aptera's embracing the 'right to repair' approach means someone will come up with a redesign of the front wheel skirts as an aftermarket product that will accommodate any tire/wheel combination that can work with the Elephe wheelmotor.
Depending on how good a driver Aptera attracts over time, including second and third owners, one might see a trend toward the forumla-1 esthetic of skirt-less wheels. Sure it will lower the range of the 1000 mile Aptera to 880 ... but the grocery store is only 4.6 miles away.
Heck, there is probably a way to use the friction and pressures on the tire that it would light up a strip embedded into the tire creating a light show on the tire.😎
But to answer the question, when you get yours you can put any size tire on it you want.
What would be cool would be for Roush to make tire suggestions, including suspension tuning advice based on the tire chosen and whether the principle being supported is speed, safety or comfort and/or on or off road or track. It would be particularly nice if they presented the objective data.
I don't think that will happen largely because nobody except Sandy Monro has figured out how to present this kind of objective engineering data for fun and profit.
Here in Sweden, based on available number of models, 195/55R16 seem to be by far the most common 195R16 dimension. I would just stick with that unless it's somehow way less efficient than a 195/45R16 tyre.
I just checked & my own car has 209 pounds per inch of sidewall, which is slightly better than Aptera, HOWEVER, Many other users with the same model have 1" bigger rims with 238Lb/in of sidewall, which is worse than Aptera, yet none of them have mentioned any issues.
I would like 195/50/R15. It is cheap and the choice is not bad.
I'll second this. I also want more rubber and a more compliant ride. Remember folks: with 3 wheels you WILL hit every pothole since you can't straddle them. 45% profile tires will pulverize your spines.
Aptera has a MAXIMUM of 223 pounds per inch of sidewall.
(3.45" sidewalls, with a maximum 770Lb/tire)
Tesla 3 has a MINIMUM of 201 pounds per inch of sidewall with its smallest 18" wheels.
(4.15" sidewall max, & max about 835Lb/tire minimum)
"Ride" depends mostly on personal preference & the OEM spring/damper selection.
45 is a fairly standard profile these days. Base Tesla's come with a 45 profile tire and the performance versions have a 30 or 35 profiles. This is true even for the Telsa SUV's. Right now Aptera is running a Continental ProContact, which is a good all season tire.
22.9" is the overall diameter of the 195/45R16 standard size tires. 25.2 is a bit on the big side... Would need to be tested before I'll start buying tires in that size... In any case I'll be watching to see how things go for the first Aptera owners with this stuff as it develops further.
The other thing to remember is the Elaphe motors may not allow a smaller rim (Ie: 14" or 15" rim) so we might be stuck between a 16" rim and a tight wheel fairing. I would also like a little more meat in the tire, and just looking at the 195/45R16 tires there are very few options. Just a couple of highway tires, one snow tire, and no all terrain or hardened tires with additional belts or puncture protection...
Looks like there's a couple of comparable sizes that have several different snow tire options, but no all terrain options. Obviously efficiency is king, I'm just worried about rock punctures on an all season...
https://tiresize.com/tiresizes/195-45R16.htm
If 15s are possible (Elaphe says the M700 can use a custom 15" wheel)
https://tiresize.com/tiresizes/195-50R15.htm
https://tiresize.com/tiresizes/185-55R15.htm
https://tiresize.com/tiresizes/205-50R15.htm
The argument for why it's ok is that the aptera doesn't weigh a lot so it will just "bounce" over potholes without damaging anything... I still want more rubber though, and three wheels means more weight per wheel than 4...
We'll need to wait for a little more information before we have a good idea of what will work. I expect that Aptera's testing and subsequent tire choice will satisfy most. If they stay with a P195-series tire and you're looking for a comfortable ride, something in the range of 60 to 75 aspect ration may be to your liking (depending on the design rim width and the interior dimensions of the wheel covers). I'm content with staying tuned to Aptera's progress along with Roush's contribution
Low profile may be a good option for those who live in cold climates and need extra traction for snow and ice.
Bruce is correct the P195/45R 16 was first announced, but they where assessing a slight large tire like a 205 or 215 at least in the rear tire for better pothole protection. All of which are common size 16 tires,
(I think I heard a 185 may have even been “in the mix, when assessing”???)
Remember these are development vehicles, alpha through delta to assess best choices for ultimate crash test to production
I am not sure that the P195/45R16 tires they are using are particularly low profile?