What is the smallest tire I can go with?

[massimofinance]

I have 8" tires on a trailer to carry a wave runner. Are the tires too small for the highway?<br /><br />Thanks.<br /><br />MAX

 

[BF]

Re: What is the smallest tire I can go with?

lots of people use them, but personally I don't like 'em. Small wheels have to spin fast... If you use 'em, be extra paranoid about keeping an eye on the tires and make sure that your bearings are in top shape and appropriately lubed.<br /><br />Seems to me like most times there's a trailer pulled over with some kind of failure, it had 8" wheels on it. Earlier this spring I saw 2 within a mile of each other.... Don't know if they were just tire failures or bearings. They had just failed (were still in the head scratchin' stage). I see more failures early in the season... I think the neglected trailers get weeded out by a couple of long highway runs.

 

[Silvertip]

Re: What is the smallest tire I can go with?

There are several sizes of 8-inch. Check the tire size and load capacity on the sidewall of the tire you now have. Buy tires of equal size with equal or higher load ratings. Going smaller creates a couple of problems 1) overloading, and 2)legal issues if you have an accident due to a tire failure caused by installing wrong tires. Is it a long shot??? Certainly. But why on earth for a couple of bucks would you want to install "smaller" tires.

 

[Mark42]

Re: What is the smallest tire I can go with?

8" tires are fine. Just make sure they are properly inflated and the bearings are packed with grease.<br /><br />8" tires have an advantage over larger tires because you don't have to back the trailer in as far to get the boat or jet ski to float.<br /><br />To compare an 8" tire to a 12" tire for RPM it comes out like this:<br /><br />8" tire is aprox 16.7" in diameter and 52.4" in circumferance. A 12" tire is aprox 20.5" in diameter and 69.7" in circumferance. Divide each circumferance into inches in a mile and you get 1209 for the 8" and 909 for the 12". So at 60 mph that is one mile a minute or 1209 rpm for the 8" and 909 rpm for the 12". So the 12" is turning about 25% less RPM at 60 mph. But at these low RPM numbers I doubt it makes much of a difference.

 

[craze1cars]

Re: What is the smallest tire I can go with?

Here's my calculation...25% more RPM = 50% more heat = 75% more bearing/seal/grease wear = 100% more bearing maintenance. Of course I just pulled this outta my behind, but I honestly think there's a bit of truth to it.<br /><br />I'd keep after those bearings if I were you as the faster spinning does tend to cause an incremental heat buildup if something is even just slightly askew, but if they're rated for highway use, the tires themselves should fine.

 

[rwidman]

Re: What is the smallest tire I can go with?

Think of how far into a pothole those 8" tires will drop! <br /><br />I would be looking for the largest tires that will fit the trailer, especially for highway use.

 

[roscoe]

Re: What is the smallest tire I can go with?

Jimminy cripers, people have been using 8" wheels on their trailers for 50 years. If they are rated for the load, and inflated properly, and the bearings are maintained, they will be fine.<br />This goes for all trailers.<br /><br />Most snowmobile trailers have 8" wheels too.

 

[ndemge]

Re: What is the smallest tire I can go with?

You need to put on a lift kit and put on some 33" super swampers.

 

[Silvertip]

Re: What is the smallest tire I can go with?

Larger wheels and tires roll easier = less power required = better fuel mileage.

 

[BillP]

Re: What is the smallest tire I can go with?

13" wheels with 55lb pressure or 8" wheels with 125lbs pressure...which has least resistance? Both tires have near identical load rating and are on boat trailers.

 

[massimofinance]

Re: What is the smallest tire I can go with?

Thanks for all the replies!

 

[woosterken]

Re: What is the smallest tire I can go with?

I have 8" tires on my tandem axle trailer and never had a problem.as mentioned keep an eye on tire pressure and keep the bearings greased.<br />I like them, I can launch my boat when the water level is down while those with bigger tires can't <br />ken

 

[Mark42]

Re: What is the smallest tire I can go with?

Originally posted by Upinsmoke:<br /> Larger wheels and tires roll easier = less power required = better fuel mileage.

Larger wheels and tires have more wind resistance than a smaller setup. That would indicate that they use more fuel. <br /><br /><br />Actually, I bet the average vehicle will not notice any difference in fuel consumption between the two.

 

[phantoms]

Re: What is the smallest tire I can go with?

I doubt the vehicle would notice much difference between larger and smaller tires either, but the smaller tires would wear faster along with more stress on the hubs. The only difference on the vehicle may be that the trailer notices smaller bumps and holes in the road than with larger tires.