Car topping and accelerated tire wear?

I’ve been kayaking for about 5-6 years. During that time, I’ve had 2 cars. Before that, I had quite a few.

The two cars I had since owning a kayak, tires don’t last nearly as long as before. More over, I’ve had several episode of un-even wear on the tires. At first, I thought I just had a car with suspension that just doesn’t keep alignment well for long.

When this happens to the second car, I’m naturally wondering if car topping the 60 lb kayak has anything to do with that.

How about the rest of you? Do you notice any change on tire longivity? Or do I just had some fluke coincidence.

No problems here
On my current car, I got nearly 140,000 miles on the factory-original tires, and for the last 7 or 8 years, nearly all my summertime driving is with one or two boats on the roof.

This is not typical for me, but I do usually do pretty well on tires, normally getting 90,000 to 100,000 miles on a set of tires on the vehicles I drive for my job. I really can’t imagine boats on the roof making any difference. As far as wind resistance goes, the boat’s resistance can be noticeable at highways speed in the case of canoes, but still no different than driving into a reasonable headwind without boats (and with a kayak on the roof, I’ve never noticed a thing, ever, no matter how strong the wind, though I’m sure some small effect is present). The weight sure doesn’t matter, since a single passenger weighs quite a bit more than three fairly heavy boats.

Sounds like the most important variable - the type of car - should be considered. After all, you did say that your boat haulers are not the same cars that you drove back when your tires lasted longer.

No, I just got 60k from my Accord’s
factory tires, and the car has had a canoe on top for most of those miles. And I used to get 80k from our Outback, again with many road miles carrying a canoe.

But tires can disappoint. Today’s tires often mix rubbers across the tread, and small variations may have marked effects. When we replaced the factory Dunlops on our Accord with the same (supposedly) tires, they developed a hum and the dealer found cupping and feathering. Because we had the car aligned and balanced when the replacement tires went on, they gave us two replacements on warranty. But the other two are humming…

If you read the customer reviews on tirerack, you’ll see widely varying reports for the same tires on the same car. All you can do is try to go with the majority who report good results.

Non here, but then again, I have been…
car topping boats since before most of you were born, so I would have to stop car topping them to really find out !

Jack L

No changes here. But, I have noticed that I substantially increase tire life by maintaining my tire pressure at the maximum sidewall pressure rather than the much lower pressure recommended by the vehicle manufacturers.

im sorry
140,000 miles on a set of tires? Especially OE…? Remind me not to ride with you on a rainy day.

Ryan L.

what kind of cars
A lot of new cars wear tires unevenly do to factory spec alignments that help with performance.

Tires are cheap compared to wreaks.

Ryan L.

I can’t imagine 60 lbs on the roof
would cause more tire wear than a 180 lb person in the car.

Sign me up

– Last Updated: May-01-12 8:42 PM EST –

I would love to have this problem. Car topping boats on so many trips that it affects tire wear. Sounds like heaven to me.

Uhhhh, Like Jackl…
…been cartopping canoes since the '70’s, so I wouldn’t have anything to compare with. But I would seriously doubt one kayak would make a difference. Gravel roads and bad rural highways are what do my tires in. Even IF it increased your tire wear a bit, why worry? I would NOT consider giving up paddling for buying tires sooner. But I’m one of those people that views my vehicle as a “Tool,” not a “Toy.”

Gravel roads do my tires in ever 25,000 miles or so. I buy good ones then get a good chunk back on the tread warranty. Worth it.

Afterall, its just money.

Ryan L.

I’ll bet you could induce tire wear …
… if your boat was on the rack cockeyed

does boat turn sideways?
If the boat twists sideays then that could be hard on tires. The boat must be paralell to your car. Bocks on all 4 corners can help with a canoe. Saddles work great for the kayak

Even though roads in some places are kinder to tires, 140K still sounds like “bald tires” to me.

We’re lucky to get 50K on a set of tires around here, trucks and other tall vehicles even less. This assumes that the vehicle is kept aligned and wheels balanced. Too much rough pavement, no pavement, curves, etc. for really long tire life.

Federal government issues an annual rating of tires by brand and model, which breaks the USA into 3 tire-wear categories. We’re in the worst category. But even if GBG is in the best category, 100K+ sounds like pushing things a little too far.

Ya beat me to it
The few times I rooftop, I like to put the kayak on the passenger side (if it’s empty). But I doubt it matters much to the vehicle. If it did, there would be millions of lopsided commuter cars out there.

Lots of variables (how are your shocks?)
Tire quality varies a huge amount.

Owner diligence about vehicle alignment, tire pressure maintenance, and rotation/balancing varies a huge amount.

There might be something wrong with one of the suspension components OTHER THAN your tires.

For example, how healthy are your shock absorbers??? The old shove-a-corner-of-car-down test only reveals very worn shocks. I had a truck that passed that test at 48K miles. When I took it in for routine wheel balancing, the shop told me I needed new shocks. I was surprised, till I thought about it a bit. Yes, actually, the truck did wag side to side when going over speed bumps, which it had not done earlier in its life. I trusted their judgment despite wondering if they were pushing unnecessary stuff on me. As soon as I got behind the wheel again, I knew they had given me good advice. It handled much better with the new shocks. What had happened was that I just got used to the feel of gradually-worn shocks. Same thing happens with brakes. You should check those, too. Maybe one is sticking.

I doubt that one boat on the roof is causing the abnormal tire wear, unless your suspension is so soft that it makes the rig wallow.

absolutely none at all
In fact my current set of tires didn’t seem to wear much last summer, almost peculiarly so. Maybe I’m getting some aerodynamic lift from the kayak.

I shouldn’t make fun. Back in the days of ground-effects race cars, it was theoretically possible for a car to run at speed on an upside-down road, as long as the speed was maintained…

Smaller wheels on your last 2 cars?
Did you switch from driving a vehicle with large wheels to one with small wheels?

The small ones last fewer miles because they’re making more rotations per mile.

Keep them properly inflated.

larger wheels!
“Did you switch from driving a vehicle with large wheels to one with small wheels?”

Actually the 2 newer cars has larger wheels. I bought both used so I got the big wheels just by chance.

Now that I’ve looked into the whole issue, I may have been wrong about tire longivity. I’ve driven a lot more the last few years, a lot of it driving the boat to the water… So although the time between tire change were shorter, the distance I drove them were longer. 2 of the tires are at least over 50k. Maybe more, since I bought both used.

It’s not so much tire longivity that cross my mind. But it’s the uneven wear (though someone mentioned wear on the inside often the case in newer cars) that got my attention.

It’s been drummed into my brain uneven wear is a sign of bad alignment. Well it was. But why was it off alignment every year! And only the latest 2 cars?

So maybe nothing to do with kayaks. Just coincidence.

Don’t run over so many marmots.
It’s interesting about shock absorber life. Click and Clack were saying shocks need routine replacement at about 60k. I’ve had only one car need new shocks that soon. Our first Accord went 235k without ever needing shocks, and our second, at 185k, is just fine too. I think it has to do with the original quality of the shocks. And marmots.