What are the pros & cons of a 21" vs 19" rim/tire in the front?

 

Without trying to go into detail, I have ridden both quite a bit and the 19" handles much better and I'll bet the later models with the fat tire is even better although I have never ridden one. Of course if you like the looks of the skinny one best, you wont care.

 

Maybe the 21" has less unsprung weight than the 19".
Also, would believe the 21" would handle pot holes at highway speed better than the 19".
Definitely the 19" is superior to the 21" in the turns and twisties.

 

Not really true. The 19" tire has a taller sidewall making the difference in diameter of the 2 wheel/tire combos less than 1/4".

IME, the 19" gives me about 24,000 miles between tire changes, the 21" around 8,000 - 9,000 miles. (That's with a fair amount of twisty riding on both)

Having ridden both for thousands of miles, the only thing the 21" has going for it IMO is "looks", and that's just some peoples personal preference. There's nothing about the 21" that will outperform or outlast a 19".

 

I changed from 19 stock to 21 aftermarket with the same wheel width and I barely noticed any differences. I also lowered my fork. But my objective was looks/style/uniqueness...wanted my ride to look different from all the other sporties on the road.

 

The Dunlop tire catalog indicates the following overall diameters.
Model D-404 general purpose all around
100/90-19: 25.82"
80/90-21: 26.69"

Model D-401 , H-D approved cruising tire
90/90-19: 25.85"
100/90-19: 26.45"
note: 21" not available

Model D-402, H-D approved touring tire
MH90-21: 27.20"
note: 19" not available
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There very little difference in overall diameter, 0.24", between 100/90-19, D401 and the 80/90-21, D404.
There is difference of 1.35" overall diameter between the 100/90-19 , D404 and MH90-21, D402.
If the two D404 tires are compared there is only, 0.88" difference in diameter or 0.44" radius.

To my knowledge the 90/90-19 was only used on the H-D Rocker model with rear fender attached to the swing arm
not the frame and is not considered in the comparisons.

The stock OEM tire on the 88C & 1200C is the larger diameter MH90-21.
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21x[?] and 19x[?]? Cast, carbon, spoke?

to many variables. If you mean the commonly found narrow glide custom wire spoke wheel vs the commonly found 13 spoke cast wheel, then 19x2.5 will perform "better" for some, with less flex, and more direct response, and less maintenance. The narrow 21×2.15 in stock configration will chase imperfections in the road but, deliver a softer ride, and more maintenance.

The common 19x2.5 cast wheel require less maintenance than most, not all, spoked wheels, you kinda just put tires on and balance them and hopefully dont look at them again for bout 8k mi.

You'll be paying close attention to the tire tread on a 21x2.15 in stock configuration as well and may need to relace it more often if you keep it stock. Also will be minding the spokes and their condition, rim's condition/true, tube, rim strip... blah blah. Style...

if you mean aftermarket, it's a case by case basis. My fxdwg 21 stock wire wheel vs the cast one i had made are a night and day difference. The stock 21x2.15 spoke one doesn't hold a candle to the cast 21x3.5. All that to say that there's more to it than just the diameter of the wheel.

 

My cast aluminum 13 spoke 19" H-D wheel measures 2.135" , inside bead wall, which probably considered nominal 2.15" width.
Agree, the 19" x 2.15" wide cast aluminum wheel is more rigid than a laced steel,19"x 2.15" wide wheel, especially a laced 19" x 2.15" spun aluminum wheel
Cast 19" x 2.15" vs laced steel 19 x 2.5" ?
Have not noticed any H-D cast 21" x 2.15" wheels.

 

Timken, 205PP, 25 mm bore , rubber sealed bearing delivered today from Amazon, no foreign county on packaging, therefore , made in the USA.

 

so to clarify will the 19x2.15 front wheel fit on a sportster with stock size of 21x2.15 with same axels/forks? I am looking at trying to swap/ purchase smaller sportster wheel for my bike such as the 19inch spoked or mag wheel to have the same front tire as roadster/nightster/48 but trying to find more info if wheel will go right in or what other modifications must be made to achieve this. thank you.