Tire sizes for 26/27 , will 450/475-21 be ok on my roadster pick up?

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Oldrusty26
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Tire sizes for 26/27 , will 450/475-21 be ok on my roadster pick up?

Post by Oldrusty26 » Mon Aug 08, 2022 1:06 pm

Good afternoon guys ,
Just wondering if it’d be ok to use 450/475-21 tires on my roadster pick up project ? Will I need different sized tubes and flaps as well ?

Thanks in advance !!

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RajoRacer
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Re: Tire sizes for 26/27 , will 450/475-21 be ok on my roadster pick up?

Post by RajoRacer » Mon Aug 08, 2022 1:14 pm

If you currently have 21" wheels, you can !


Moxie26
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Re: Tire sizes for 26/27 , will 450/475-21 be ok on my roadster pick up?

Post by Moxie26 » Mon Aug 08, 2022 1:41 pm

You may notice a difference in low pedal that you may have to start out a little easier, keep the low pedal in a little bit longer before getting into high gear only because of the slight increase tire tread diameter. No problem with a 21-in rim / tire size.


Topic author
Oldrusty26
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Re: Tire sizes for 26/27 , will 450/475-21 be ok on my roadster pick up?

Post by Oldrusty26 » Tue Aug 09, 2022 7:59 am

Thank you guys for all your help


Alan Long
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Re: Tire sizes for 26/27 , will 450/475-21 be ok on my roadster pick up?

Post by Alan Long » Wed Aug 10, 2022 7:35 am

Excuse my ignorance but how can a Tyre be two different sizes?
I understand Tubes come marked 4.40 / 4.50 x 21” but they can be stretched or squeezed into the Tyre..
Alan in West Australia


Moxie26
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Re: Tire sizes for 26/27 , will 450/475-21 be ok on my roadster pick up?

Post by Moxie26 » Wed Aug 10, 2022 8:09 am

Hello Allen.. 21 in. Diameter rimmed tire will fit on a 21-in rimmed wheel.... The size associated with the 21-in rim indicates the outer width and diameter of the tire "rubber against the road". Tube manufacturers May make their tubes a little bit beefier to fit a range of bigger diameter tires against that 21 inch rim.


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Re: Tire sizes for 26/27 , will 450/475-21 be ok on my roadster pick up?

Post by TXGOAT2 » Wed Aug 10, 2022 8:21 am

Ex: 4.50 X 4.75 X 21: 4.50 is the nominal section height of the tire, 4.75 is the nominal section width, and 21 is the nominal rim size the tire will fit. This applies to tires made for drop center rims. None of these figures represent actual tread width. I've seen a great many tires the actual measurements of which do not match their nominal sizes. Overall diameter is just that, presumably when mounted and inflated. A typical 4.50 / 4.74 X 21 tire would have an overall diameter of about 31". Tread width would be around 3.0 to 3.5" .

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