Front Wheel, How Big Can I Go?

Discussion in 'Touring Models' started by franka, Aug 18, 2013.

  1. franka

    franka Active Member

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    2007 Road King Classic running stock 16x3.5 front spoked wheel. Want to switch front wheel to Fat Daddy 50 spoke and wondering how big a wheel I can run without having to change anything? Im guessing 18" is the one but would really like to go with 21". Most likely will change from dual calipers to single left caliper
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  2. tourbox

    tourbox Senior Member

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    You can go to the 21" but will have to change your fender as well. Plus probably re-spacing of the wheel.
    tourbox
     
  3. franka

    franka Active Member

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    If I go 21" does the triple tree need to be replaced/upgraded and what about fork tubes, do they need to be modified to make up for wheel height and travel?
     
  4. gusotto

    gusotto Junior Member

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    Had a friend who put a 21" wheel on his Ultra.
    Had to trim the fender.
    After he finally sold the bike, he admitted that even though it looked cool, it was a bear to handle at low speeds.
    Said he wouldn't recommend the 21".
     
  5. dbmg

    dbmg Experienced Member

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    +1. If you are planning to show bike and not ride as much, then go for it along with the additional mods to bike to get wheel assembly to fit. Other wise you will never beat stock configuration for ride quality and handling..
     
  6. 173ABN

    173ABN Active Member

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    21" on my 09 Road king no problem with fender
     
  7. HDDon

    HDDon Experienced Member Contributor Retired Moderators

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    I'm not a custom builder, but with the ones I see in the Mags. that I get they always either cut and reweld the neck at a greater angle or put on raked triple trees. This is so the builders retain the correct trail and the bike's steering remains somewhat neutral.
     
  8. 173ABN

    173ABN Active Member

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    Don mine is a stock frame and tree 17" on rear and have had no trouble w steering
     
  9. Slo-Ryd

    Slo-Ryd Junior Member Contributor

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    I've researched this extensively since i'm considering going to a 21" over the winter. From what i can gather a 21" will fit with the stock fender. Remember, as the rim diameter increases, the sidewall of the tire gets decreased to compensate for it. Take a look at your stock 16" wheel and tire for example, there is about 4" of sidewall. Now look at a 21" on a bagger, even online if ya hafta. Notice how small of a sidewall it now has. If you do quick and dirty math, going fro 16 to 21 increases the diameter by 5" which translates into 2.5" per side. Deduct that from the sidewall on a stock front tire and it would leave about a 1.5" sidewall. Not very practical BUT, there's still room alot of room from the stock tire diameter to the fender now, which will allow to run a 21" tire with a slightly larger sidewall. I plan on measuring how tall a 21" wheel and tire is compared to my stock height. I doubt it's any more than an inch or two at most. I see plenty of 21's running around here with original front fenders. At 23" and up is where raked trees or cutting and raking the neck becomes necessary. They're putting 30's on show bikes nowadays. Silly if you ask me and makes the bike practically useless but brings me back to my days as a kid and reminds me of my Bigwheel. Maybe thats what's visually appealing. Hope my explanation of the wheel size makes sense. It's common in the auto tire industry and is called going +1, +2 etc. :s
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  10. dbmg

    dbmg Experienced Member

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    And do not hit any bumps or potholes... For the air and sidewall is what cushions the blow of pot holes.. Like I suggested before all show and no go.
    It's your ride you decide.....