Difference? Middleweight/balloon Schwinn

Discussion in 'Motorized Bicycle General Discussion' started by Greybeard, Feb 23, 2011.

  1. Greybeard

    Greybeard New Member

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    I have a '60s Schwinn, freebee, that has 1 3/4 tires, and measures 19" crank to top of stem. Is the real difference between the Balloon tire and the middleweight bikes just in the tire/rim, or is there more. Did the larger tired bikes have the same frames, or were they different altogether?
    Thanks
    Mike
     
  2. bairdco

    bairdco a guy who makes cool bikes

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    normally, a middleweight has a skinnier fork, fenders, and frame (to go with the skinnier wheels and tires.) a lot of the bikes will take a wider rim, but you'll have to find that out for youself.

    also, the rim sizes are usually different. if it's a 1 3/4, it's different from a 1.75, and the tires aren't interchangeable.
     
  3. Fossil

    Fossil New Member

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    Am I missing something here?
    Isn't 1.75 the decimal equivalent of 1 3/4?

    Jim
     
  4. ocscully

    ocscully New Member

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    Yes they are the same probably everywhere except when it comes to measuring tires. Schwinn back in the day were trying to make it so that you had to buy replacement tires and tubes only from an approved Schwinn Dealer rather than the local Department Store or Auto Supply. Hence Schwinns Middle weight tire was a 1 3/4 and only fit their S-7 rim, where everyone elses was 1.75 and would fit the standard 26 in. rim. Schwinn also did the same thing with their 26 X 1 3/8 in. and 24 X 1 3/8 light weight tires. Schwinns were made to fit their 26in. S-6 rims and 24in S-5 rims where the other manufacturers used tires that fit 26 X1 3/8 EA-3 rims. Here is a link to the Sheldon Brown article on tire sizes. Tire Sizing Systems

    ocscully
     
  5. Fossil

    Fossil New Member

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    Okay thanks for clearing that up. I learned something tonight!

    Jim
     
  6. Venice Motor Bikes

    Venice Motor Bikes Custom Builder / Dealer/Los Angeles

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    There is a difference between the heavyweight & middleweight frames... It's really noticeable when you look at the fender bridge on the frames; The heavyweight frames are noticeably wider there because of the ballon tire fenders.
    Also, there were mostly heavyweight bikes made in the 1950's, & mostly middleweight's made in the 1960's. Schwinn made a big return to the ballon tire cruisers in the mid 70's.
     
    #6 Venice Motor Bikes, Feb 23, 2011
    Last edited: Feb 23, 2011
  7. Greybeard

    Greybeard New Member

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    I measured around the chains stays and seat stays. The fenders on this bike set inside the seat stays at the fender bridge by 3/16th on one side and a heavy eighth on the other. I noticed the fenders for the balloon tire bikes have dimples at the fender bridge where the seat stays go through. Where the rear tire runs through the chain stays, there is a total of 1 9/16th around the tire. Plenty of room for the larger balloon tires.
    Any comments would be appreciated.
     
  8. bairdco

    bairdco a guy who makes cool bikes

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    it's really a trial and error process. as in, the only way to find out if it works is to try to stuff the bigger tire in there. i've had bikes that fit larger tires by a few mm, and i've had to use different size sprockets just to get the wheel back enough so it doesn't rub.

    you still have the problem of the 1 3/4 tire, though. i dunno if anyone makes anything wider in that oddball rim size.
     
  9. Greybeard

    Greybeard New Member

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    I guess I left something out. I was thinking of either buying Worksman wheels and going full balloon 2.125" or relacing these for a 2 X 1 3/4 tire. it's smaller than the full balloon. but 1/4 inch larger than stock and made for the S7 rim. Sometimes for the sake of keeping bandwidth down I take shortcuts in communication. Thinking maybe buying some of the wider fenders and seeing if they fit. If not, resell.
     

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