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Old 12-06-2022, 09:35 PM   #1
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Rim size needed

I have a ‘15 clipper fq. I want to switch out the rims and tires and was looking for the size that works. I have 13” on there now and want to install 15”. Anyone have the exact size that will fit. I’ll get 215/75/15’s but I’m stumped with the rim size, 5”,5.5”,6”?
Thanks
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Old 12-06-2022, 09:43 PM   #2
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Quote:
Originally Posted by Lagman View Post
I have a ‘15 clipper fq. I want to switch out the rims and tires and was looking for the size that works. I have 13” on there now and want to install 15”. Anyone have the exact size that will fit. I’ll get 215/75/15’s but I’m stumped with the rim size, 5”,5.5”,6”?

Thanks
Have you checked your clearances? Thats a pretty huge jump in diameter and width.

Have you found 215/75/15 in a ST tire?

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Old 12-07-2022, 07:05 AM   #3
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I have plenty with the axle flip and new 2509# springs and shocks.
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Old 12-07-2022, 07:33 AM   #4
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We use a math formula in the tire biz to quickly approximate different tire size diameters when a specification chart is not handy.

Using your 215/75/15 tire size for example means the... section width is 215 mm/the aspect ratio is 75 per cent/and the rim diameter is 15 inches.

To convert all that to a diameter in inches, we multiply the section width X the aspect ratio X 2

Then divide this number by 2540 (as there are 25.4 mm in an inch)

Now we add the wheel diameter to this number that we already converted to inches above

Section width X aspect ratio X 2/2540 + rim diameter

215 X 75 X 2 (=32,250)/2540 = 12.696 inches + 15 inches = is 27.696 in total diameter appr.

Supposing you have 175/80/13 tires currently on your trailer that is 175 X 80 X 2 (=28,000)/2540 = 11.023 inches + 13 inches = 24.023 inches appr.

that is an appr diameter difference of 27.696 - 24.023 = 3.673 inches.

However that difference is half once it is mounted on the hub/center so you would need a spare 1.836 inch clearance from the bottom of your trailer to the top of the tire in order to use that size. Take into account the bouncing the trailer does as it goes down the road to make sure you have this clearance to spare.

Also if you remember the section width of a tire is in millimeters and 25.4 mm = 1 inch.

A 215 mm wide tire is 40 mm wider than a 175 so you have to also account for this in the spacing between the rim and the frame/or fender skirting if it comes over the tire. This is also where you have to make sure of the offset numbers of your replacement 15 inch wheels to make sure they do not offset the new tires so they rub on the frame or fender skirt.
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Old 12-07-2022, 07:44 AM   #5
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To answer your question on rim width, you may have a hard time finding a 215/75/15 tire in a trailer tire. The common sizes are 205/75/15 and 225/75/15.


The recommended wheel width for a 205/75/15 is 5.5 inches and the recommended width for a 225/75/15 is 6.0 inches.


https://www.goodyear.com/en-US/tires...ce/sizes-specs
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Old 12-07-2022, 07:48 AM   #6
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Cool! I know I have at least 6” above the tire. I’m just not sure about the width. I have about 4” there and I agree with the 205’s. I just want to get the right rims. How do you measure the offset. Edge of rim to hub face?
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Old 12-07-2022, 07:58 AM   #7
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How do you measure the offset. Edge of rim to hub face?
Thanks

This will show you how/

https://www.wikihow.com/Measure-Wheel-Offset

Most true trailer wheels are going to have the same offset (usually zero offset), but you want to make sure. Zero offset means the wheel hub is in the middle of the width, so you have an equal amount of tire both ways.


We had a customer one time who came in with some specialty aluminum rims he ordered off the internet to put on his trailer. We did all the swapovers on his tires, then found out the rims had a different offset and the tires rubbed the frame when remounted on the trailer. He had to pay us again to swap it all back. I think he probably left here calling me worse names than my ex does.
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Old 12-07-2022, 12:12 PM   #8
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Why go to 15s? Are you going Elk hunting? i saw a trailer 9500 ft on 13s in n.m. Took me 2.5 hours to go 9 miles in 4x4 no trailer . what the trailer structure was,,, prob. loose.
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Old 12-07-2022, 02:54 PM   #9
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First they’d be easier to find and replace on the road than 13” HL and 15’s would take a little more beating
With HL maybe D or E. I have the room…
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