Going From Stock Tires to (Non-OEM) Car Tires?

[WackyDan]

Dan, in all the Car tires I have used ( for the rear ) ...they have been in 16 to 18 PSI range ....well over 100,000 miles of riding ...... I have never had a tire even SLIP on the Rim let alone break a BEAD ....Over-inflating a Car tire ( for the Spyders weight ) is #1. - giving you less traction ...and #2. - a punishing ride..... This is tire Science not " what someones Butt told them " ...... To ALL those tire Science doubters just try this ..... On your Spyder , deflate a tire to about 5 psi ( this won't break the Bead on a parked machine ) ... now start IN-FLATING it, you can Actually see the tire FOOTPRINT getting smaller ....this begs the question - How can a smaller Footprint give better traction - Answer IT CAN'T..............and if you think it CAN - then you should " PROVE IT " ........ Mike :thumbup:

Prove what? What exactly are you asking me?

The answer is simple. At the same tire pressure the car tire will out perform stock kendas. You want to go lower fine, that is choice. I don't know how you ride Mike. I've met a lot of people that say they ride their spyder hard and then end up riding with them and find out their own perception of their riding style is not anywhere near reality. I've seen some people here suggest some pretty low psi numbers which quite frankly probably weren't safe for all riders and situations.

I'm well aware of what air pressure does for tires. I run my rock crawler at 3-5 psi per tire for traction, but I have dual beadlocks.

Again... not here to get in an internet pissing match.

 

[UtahPete]

This is all subjective based on the car tire you choose... but with the right car tires I've:

• Had way better dry traction front and back
• Had way better wet traction front and back
• Had way better standing water performance front and back

The Kumho that I tried on the rear of my GS lasted 11k miles - about 1k more than the OEM Kendas. The Kuhmo was a fine touring tire, but overall it's dry and wet performance was pretty bad. Only benefit of the Kumho for me was even tread wear across the entire tire width.

On the GS fronts the Bridgestone Potenza RE-92's were absolutely awesome.
On the GS the best rear I had was the Toyo Proxes 4 (no longer made). That tire was super sticky in the dry and it's wet and rain performance was incredible. Between a nail in one Toyo and selling the GS I never figured out what miles I could get to with the Toyo (on the GS)

On the F3-S I switched to the Federal Evos for the fronts. Did it early. Bit stickier than stock and better in the rain. I switched out the Kenda fronts at 4500 miles and to be honest I would have been ok keeping the OEM fronts, but decided to switch early.

On the F3-S rear I have once again a Toyo Proxes 4. My OEM Kenda was ready for replacement near 4500 miles. After 5500 on this current Toyo it looks like I might make 8k miles before needing a new rear. So I'm not getting great mileage out of the rears on the F3. I chalk that up to riding style. My Spyder doesn't do low heat around town puttering. When I ride I'm out for 8+ hours a day of riding twisties with hard braking and acceleration. No burnouts other than some wheel slip now and then.

Best advice? Any car tire is going to perform better than the Kendas and wear evenly. You may or may not get more miles out of the rear specifically. The Kumho is fine for many, but I suggest spending the extra $ on something better like the Yokohama s drive 205/50R15. It may even be in the same price range but people seem far happier with the Yokohama than the Kumho.

As for air pressure I'll only say you will find lots of opinions and a lot of apparent tire experts here. Yes the Spyder is lighter than a car and thus the tires aren't even pushing their load ratings. I've run 20-22 PSI on the fronts for thousands of miles with no issues and anywhere from 28-30 on the rear with no issues. You go too low of a PSI and the tire may create too much heat via sidewall flex and may break a bead in an abrupt swerve. Some here suggest some very low PSI in the tires.... "Tread" carefully... Get it?

I buy mine for performance and not price and not the miles I get out of them. True, I wish the tires would last longer on my F3-S but that is probably my fault more than anything else. Just remember that at some point after your 2nd or 3rd rear tire you should have your rear bearings inspected and potentially replaced.

Thanks for sharing this info and perspective.

 

[BLUEKNIGHT911]

NOT - a pissing match

Prove what? What exactly are you asking me?

The answer is simple. At the same tire pressure the car tire will out perform stock kendas. You want to go lower fine, that is choice. I don't know how you ride Mike. I've met a lot of people that say they ride their spyder hard and then end up riding with them and find out their own perception of their riding style is not anywhere near reality. I've seen some people here suggest some pretty low psi numbers which quite frankly probably weren't safe for all riders and situations.

I'm well aware of what air pressure does for tires. I run my rock crawler at 3-5 psi per tire for traction, but I have dual beadlocks.

Again... not here to get in an internet pissing match.

Dan I WASN'T asking ...YOU ...to prove anything AND I wasn't asking YOU ( personally ) .....anything .... the - " and if you think it can - then you should " PROVE It " ...the you here was generic for all the Science doubters that are extremely vocal and negative about Science ......... So you pretty much mis-understood what I was trying to convey :banghead::banghead::banghead: .......... When / if I decide to have a fight - I rarely start out by HELPING that person , which is what I was trying to do for You !!!!! ............... Mike :thumbup:

 

[SPECTACUALR SPIDERMAN]

i use vredstein quatrac on my '13 rt-s and they are very good tires in quality and performance

 

[Jeffmal]

Sizes?

i use vredstein quatrac on my '13 rt-s and they are very good tires in quality and performance

Can you provide the size for front and back and how many miles you have on them. Thanks

 

[Easy Rider]

Yeah, but it wasn’t any kind of scientific data on my part, Easy Rider, just seat of the pants stuff.

Sometimes that is better, sometimes it isn't.

Sometimes people "know" scientific data but don't understand how to use it correctly.

Sometimes they make stuff up and CALL it science.

 

[Easy Rider]

Again... not here to get in an internet pissing match.

He is still pissing about my statement that a smaller contact patch will have less tendency TO HYDROPLANE.
I did NOT say it was better for overall traction.....in any conditions.
Yet he continues to chase ghosts.

 

[tehrlich]

I run 25psi up front and 28psi in the back. Ride every day and experimented countless times, and measured heat signatures.

I personally do not like the soft shoe feel of 20psi, and 15psi was like a wet sock trying to just turn in my driveway. Just not for me and others that I know.

 

[KX5062]

I run 25psi up front and 28psi in the back. Ride every day and experimented countless times, and measured heat signatures.

I personally do not like the soft shoe feel of 20psi, and 15psi was like a wet sock trying to just turn in my driveway. Just not for me and others that I know.

Curiosity, but did you track and measure the heat differentials at differing inflation figures?

Many people actively advocate for lower inflation figures, but have not posted any temperatures. That's the biggest potential problem with under inflating the tires is heat build up. The old rule of thumb was to measure the temperature of the tire when cold and then when run up. If there's more than 2-3 psi difference, then you're under inflated.

 

[tehrlich]

Curiosity, but did you track and measure the heat differentials at differing inflation figures?

Many people actively advocate for lower inflation figures, but have not posted any temperatures. That's the biggest potential problem with under inflating the tires is heat build up. The old rule of thumb was to measure the temperature of the tire when cold and then when run up. If there's more than 2-3 psi difference, then you're under inflated.

Yes, I did. Discussed my findings, and the low pressure police wouldn't have any of it.

 

[Easy Rider]

The old rule of thumb was to measure the temperature of the tire when cold and then when run up. If there's more than 2-3 psi difference, then you're under inflated.

I don't think that even qualifies as a "rule of thumb", at least not the way you stated it.

I dare say that ANY tire on ANY vehicle that is measured "cold" in the morning and then ridden 10 miles or more on a sunny summer day will gain at least that and be perfectly normal. Actually my guess is 5 or more. When running a tire on pavement that is maybe 120F or more, it is virtually impossible to NOT gain substantial pressure due to the heat.

 

[Easy Rider]

I personally do not like the soft shoe feel of 20psi, and 15psi was like a wet sock trying to just turn in my driveway. Just not for me and others that I know.

Add me to the list. The "cheap" thin OEM tires are soft and flexible to begin with; low operating pressure just makes them moreso.
A better car tire rated for heavier loads might be a different ballgame.

 

[tehrlich]

Add me to the list. The "cheap" thin OEM tires are soft and flexible to begin with; low operating pressure just makes them moreso.
A better car tire rated for heavier loads might be a different ballgame.

When I originally traded out the Kendas for my Yokohohamas, I had it at 17psi. It was a huge difference! Had them installed at James Thorne's place and he suggested to start there and move up/down. Drove the few hours from Houston back to Austin. Fantastic ride.

But, I started bumping up the psi by 2lbs. at a time, and I liked it better each time. Now, I'm at 25-26psi and it feels perfect. I don't even care that the psi police say it is wrong to go by "feel." I ride my Spyder every day because it is a blast, and I ride it how I like it. I can wear my soft slippers in the house.