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Joe Drociuk of jd yahoo groups gave me permission to share his reply to me about clincher rim and tire sizing. i really found it helpful as i really enjoy learning as much as i can. and it tells me my rims and tires are the "matching sizes" tells me very clearly i need to wait for a 90 degree day, do some hand and fore arm strengthening exercises, suck it up and be a man.....
From Joe:
"The motorcycle clincher rims of the teens and twentys changed the way they were designated around 1925. In the teens and twenty's 22 inch rims had a 3 inch tire mounted and were called 28X3. That designation was the total diameter of the wheel. 22 inch rim plus 3 inch tires added twice totalled a wheel diameter of 28 inches. Thus, 28X3.
However, the manufacturers changed the designation when they came out with 18 and 20 inch rims. The 18 and 20 inch rim was the bare rim diamter less the clincher flange as you came up with in your 20 rim measurements. Then they added the 3.85" tire twice to the rim to a total wheel diameter of aprox 27.7 inch but that figure was no longer used to designate wheel size. They now designate the rim size (20)" in your case 20 X 3.85" tire diameter only, hence 20 X 3.85. No mention of total wheel diameter any longer. Drop center rims came in August 29 for Indian and Harley on 1930 models. Tires are still designated this way on drop center rims today, , example would be as in a VL and WLA , or Indian 400-18 of the thirtys on or the more modern newer FLH, H-Dav would be 500-16 or a car tire like 600-16, or 750-16...forget the metric . Also note that on clinchers, the clincher flange is not measured and it has no effect on wheel size, that also applys to drop center rims, that flange is also not in the measurement. it just holds the tire but only then if it has plenty of air in on clinchers or the clincher rim will throw the freakin tire off, happened to me a couple of times, not funny....Joe"
From Joe:
"The motorcycle clincher rims of the teens and twentys changed the way they were designated around 1925. In the teens and twenty's 22 inch rims had a 3 inch tire mounted and were called 28X3. That designation was the total diameter of the wheel. 22 inch rim plus 3 inch tires added twice totalled a wheel diameter of 28 inches. Thus, 28X3.
However, the manufacturers changed the designation when they came out with 18 and 20 inch rims. The 18 and 20 inch rim was the bare rim diamter less the clincher flange as you came up with in your 20 rim measurements. Then they added the 3.85" tire twice to the rim to a total wheel diameter of aprox 27.7 inch but that figure was no longer used to designate wheel size. They now designate the rim size (20)" in your case 20 X 3.85" tire diameter only, hence 20 X 3.85. No mention of total wheel diameter any longer. Drop center rims came in August 29 for Indian and Harley on 1930 models. Tires are still designated this way on drop center rims today, , example would be as in a VL and WLA , or Indian 400-18 of the thirtys on or the more modern newer FLH, H-Dav would be 500-16 or a car tire like 600-16, or 750-16...forget the metric . Also note that on clinchers, the clincher flange is not measured and it has no effect on wheel size, that also applys to drop center rims, that flange is also not in the measurement. it just holds the tire but only then if it has plenty of air in on clinchers or the clincher rim will throw the freakin tire off, happened to me a couple of times, not funny....Joe"
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