Tire Size, Please Help Me!

nuttyboater

Petty Officer 3rd Class
Joined
Jun 26, 2008
Messages
81
I just acquired a boat today, i believe its a 1968 Starcraft, it has a 1968 Evinrude 65hp Sportfour on it... Anyway..

The trailer is a Dilly Trailers Model S-16.

The tire size is P145/80R12 and they are a load range C, 816lbs.

Can anyone tell me an equivalent size that will fit my wheels? I have been trying all night to find an online retailer that sells this size tires, i called a few places also, including one that i bought tires from for my utility trailer last year, and they are stumped...

One guy said he had an OLD conversion chart that says they could use a 5.20-12 trailer tire, but all i can find is a 5.30-12, incidently that was the size tire on the popup camper we used to have. So i called him again and he said no its a 5.20-12, so i looked it up on the net and sure enough i found a conversion chart on a website that showed a P145/80R12 can be replaced with a 5.20-12, but i can't find that size either.

It would suck if i had to spend the money to replace the steel wheels too, they are in fine shape, no rust and clean. The tires are checked and cracked from sitting so long, we managed to air them up today and drove her home super slow, 35mph all the way home on the highway, stopping often to check the tires and the air pressure, as well as the hubs for overheating. I plan on taking them apart and repacking the wheel bearings, been there done that on my utility trailer, so while i am new to boats i'm definitely not new to trailers.. lol

Just can't figure out what tire we need here. I would like to get them both replaced before it even leaves the driveway again. I got enough heavy duty jackstands that i can just take my time and jack it up and remove both tires and take them somewhere to be replaced and then bring them back home and reinstall, would save my nerves from having to pull it again worrying about a blowout! I don't think these tires could stand any more MN potholes!

Thanks!
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,762
Re: Tire Size, Please Help Me!

Put the 5.30 x 12's on and go. The only exception would be if the rim is narrower than 4 inches in the bead area. Lets all learn the metric system so conversions like this don't cause people so much pain. P145 (P=Passenger tire), 145 = 145 mm section width. One inch = 25.4 mm. 145/25.4 = 5.7. Close enough. A load range C provides 1045# capacity each. Which is much higher than the originals. Shame on the tire company dude not understanding this. The difference in section width is because a passenger car tire bulges out more than a trailer tire.

http://shop.easternmarine.com/index.cfm?fuseaction=catalog.prodInfo&productID=4514&categoryID=163
 

nuttyboater

Petty Officer 3rd Class
Joined
Jun 26, 2008
Messages
81
Re: Tire Size, Please Help Me!

Awesome, thanks for the confirmation guys! I will get some 5.30-12 tires ordered, that's cool that they have a higher load rating than the originals, just a bonus if you ask me!

Looks like i got next weekends project, wheel bearing repack and get the tires replaced.

This weekend is cleaning, wiring repair, seating repair, and some primer and paint.
 
Top