An unexpected side effect of roundabouts

[996GT2]

I got my tires rotated and aligned a few months ago, and was pretty surprised to find that the passenger side rear tire was worn noticeably more than the driver side rear tire, since my alignment was good and there weren't any other issues with the car. After some thinking...I finally figured it out-roundabouts! My city has been on a roudabout-building spree lately, and it's impossible to go from point A to point B without going through at least 4 or 5 roundabouts. (on an average 5 mile trip to school and back, I hit about 8 roundabouts). The passenger side rear tire used to be on the front driver's side, making it the inside tire in going through roundabouts. Because my car doesn't have an LSD (like most passenger cars out there), the inside tire is forced to spin at the same rate as the outside tire even when going through a roundabout where the outside tire is covering more ground...so as a result, it wears faster

I used to think roundabouts were pretty pointless, but with my recent realization they're even more of a waste than I previously thought...

 

[3chordcharlie]

I highly doubt that your front wheels are on an effectively solid axle, unless you've got some sort of 4x4 with everything locked up tight, in which case, you're doing it wrong, being on roads and all, and you're likely to wreck more than your tires.

 

[RGUN]

Just to clear things up, you are backwards about the effect of an LSD on the drive wheels. The lack of an LSD means that each tire is able to spin independantly of one another.

 

[996GT2]

Hmm I looked that up and that is indeed the case (Wikipedia ftw)...that makes me wonder about the uneven tire wear then since I know my alignment shouldn't be off (it was just redone at the dealership)...and it's just ONE tire that is showing more wear than the other 3-the tire that used to be on the driver's front side.

 

[RGUN]

Is the car front wheel drive?

 

[996GT2]

Yeah it's an Accord

 

[RGUN]

Possible reasons are your drivers front is underinflated, poor weight distribution, the drivers side half shaft is shorter and that is the tire that spins most often (if you're an aggressive driver).

 

[996GT2]

I check my tire pressure pretty often to make sure that all 4 are inflated to about 2-3 PSI above the recommended 32 PSI for better mpg and turn in. As far as weight distribution goes...it's about 60/40 front/back, but I'm not sure what side to side is. I'm not a heavy person though (6', 165), so the weight distribution with me inside shouldn't be that much different.

As far as the driveshafts go, that could be the case since I tend to drive a bit aggressively when I'm in a hurry to get to school in the mornings.

 

[3chordcharlie]

Originally posted by: 996GT2
I check my tire pressure pretty often to make sure that all 4 are inflated to about 2-3 PSI above the recommended 32 PSI for better mpg and turn in. As far as weight distribution goes...it's about 60/40 front/back, but I'm not sure what side to side is. I'm not a heavy person though (6', 165), so the weight distribution with me inside shouldn't be that much different.

As far as the driveshafts go, that could be the case since I tend to drive a bit aggressively when I'm in a hurry to get to school in the mornings.

Which wheel spins first (i.e. which one normally recieves power)? The unloaded wheel in a roundabout might have a tendency to spin a little if you're heavy on the gas. Do you cause the car to hop around corners?

 

[LordMorpheus]

Rotate your tires more often.

 

[alkemyst]

Originally posted by: 996GT2
I check my tire pressure pretty often to make sure that all 4 are inflated to about 2-3 PSI above the recommended 32 PSI for better mpg and turn in. As far as weight distribution goes...it's about 60/40 front/back, but I'm not sure what side to side is. I'm not a heavy person though (6', 165), so the weight distribution with me inside shouldn't be that much different.

As far as the driveshafts go, that could be the case since I tend to drive a bit aggressively when I'm in a hurry to get to school in the mornings.

So with all your regular checking of everything that could go wrong, you never noticed the wear problem.

 

[996GT2]

Originally posted by: alkemyst

Originally posted by: 996GT2
I check my tire pressure pretty often to make sure that all 4 are inflated to about 2-3 PSI above the recommended 32 PSI for better mpg and turn in. As far as weight distribution goes...it's about 60/40 front/back, but I'm not sure what side to side is. I'm not a heavy person though (6', 165), so the weight distribution with me inside shouldn't be that much different.

As far as the driveshafts go, that could be the case since I tend to drive a bit aggressively when I'm in a hurry to get to school in the mornings.

So with all your regular checking of everything that could go wrong, you never noticed the wear problem.

Well, it didn't really become that noticeable until recently. Even now, you can't notice a big difference in wear, but it's definitely there.

The point of the thread wasn't about checking this or that, but rather just to point out how unnecessary roundabouts are...

 

[alkemyst]

roundabouts are unnecessary simply based on a little extra wear on the outside of your tires You need to sit with the City Engineers stat.

 

[spidey07]

Originally posted by: LordMorpheus
Rotate your tires more often.

That's about it, you're you've got a tire pressure problem (are you measuring cold tire pressure and how accurate is your gauge?). I rotate mine every 5K miles with every oil change.

Most interstate exits are left turns so your hypothesis doesn't make sense.

 

[Jahee]

You may not have a LSD, but you do have a normal differential.. If you had a solid axle alot more would happen than uneven tire wear..

Even still.. I doubt you'd notice a difference in tire wear, even if there are alot of roundabouts..

 

[gfmucci]

I got my tires rotated and aligned a few months ago, and was pretty surprised to find that the passenger side rear tire was worn noticeably more than the driver side rear tire, since my alignment was good and there weren't any other issues with the car. After some thinking...I finally figured it out-roundabouts! My city has been on a roudabout-building spree lately, and it's impossible to go from point A to point B without going through at least 4 or 5 roundabouts. (on an average 5 mile trip to school and back, I hit about 8 roundabouts). The passenger side rear tire used to be on the front driver's side, making it the inside tire in going through roundabouts. Because my car doesn't have an LSD (like most passenger cars out there), the inside tire is forced to spin at the same rate as the outside tire even when going through a roundabout where the outside tire is covering more ground...so as a result, it wears faster

I used to think roundabouts were pretty pointless, but with my recent realization they're even more of a waste than I previously thought...

My community also has roundabouts all over. I got a new set of tires 30,000 miles ago on my 2013 Elantra. The rears are badly "cupped." I first started noticing it about 15,000 miles ago. I get different reasons for this cupping from different places. Where I bought the tires claims the cupping is due to either lack of proper alignment (I had the wheels aligned 3 times in the 30,000 miles, lack of balance (same thing) or lack of rotation. Based on their opinion, the reason is I did not have tires rotated often enough, i.e. at every 3,000 mile oil change. They rotate tires back to front, keeping the tires on the same side of the vehicle. I would think that would not help if the cause was roundabouts because the lateral forces are in the same direction. And of course at this point putting badly cupped tires on the front has even worse results..

On the other hand, my Hyundai dealer says cupping on the rears could be bad shocks, bad alignment or a result of the many roundabouts where I live. I do drive aggressively counter-clockwise around the roundabouts, probably 4 or 5 times a day.

I would like to get a new set of tires so I can get a quiet and smooth ride again - the cupping produces vibration and noise, especially around turns. But I hate to put out a lot of money on new tires until I am convinced what caused the cupping in the first place.

Your thoughts.

 

[XavierMace]

My thought would be to check the dates before posting.

 

[OverVolt]

An unexpected side effect of [blowing through] roundabouts

fixed

 

[OverVolt]

I got my tires rotated and aligned a few months ago, and was pretty surprised to find that the passenger side rear tire was worn noticeably more than the driver side rear tire, since my alignment was good and there weren't any other issues with the car. After some thinking...I finally figured it out-roundabouts! My city has been on a roudabout-building spree lately, and it's impossible to go from point A to point B without going through at least 4 or 5 roundabouts. (on an average 5 mile trip to school and back, I hit about 8 roundabouts). The passenger side rear tire used to be on the front driver's side, making it the inside tire in going through roundabouts. Because my car doesn't have an LSD (like most passenger cars out there), the inside tire is forced to spin at the same rate as the outside tire even when going through a roundabout where the outside tire is covering more ground...so as a result, it wears faster

I used to think roundabouts were pretty pointless, but with my recent realization they're even more of a waste than I previously thought...

FWIW the power goes to the inside tire and the grunt of the turning forces go on the edge of the outside tire so its the turning that wore out your tire. LSD's actually cause understeer in a FWD car could but would increase traction should one tire break loose.

 

[gfmucci]

My thought would be to check the dates before posting.

My thought is not your thought. It makes no difference what date the OP posted. The topic is still relevant.


The topic might be relevant but the date is NOT so start a different thread and do NOT bring up a thread that is this old... "Understand"...

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