Results 1 to 7 of 7

Thread: Gearing explanation please

  1. #1
    Join Date
    14th June 2007 - 22:39
    Bike
    Obsolete ones.
    Location
    Pigs back.
    Posts
    5,390

    Gearing explanation please

    This may be a real numpty question & I am happy to ware that tag but.....
    Why do push bikes have a big sprocket at the front & a little one at the back compared to the opposite for motorbikes? I saw an add for a bicycle the other day & started to wonder if it was a space issue or gearbox or something a bit cleverer.

  2. #2
    Join Date
    26th February 2005 - 15:10
    Bike
    Ubrfarter V Klunkn,ffwabbit,Petal,phoebe
    Location
    In the cave of Adullam
    Posts
    13,624
    Cos your legs can't go round at 10000 rpm like your crankshaft. Motorbike, rear wheel needs to turn slower than crankshaft (a rear wheel spinning at 10000 rpm would be about 75000 kph !). Bicycle, rear wheel needs to turn faster than your legs. So motorcycle, is geared DOWN, bicycle geared UP.
    Quote Originally Posted by skidmark
    This world has lost it's drive, everybody just wants to fit in the be the norm as it were.
    Quote Originally Posted by Phil Vincent
    The manufacturers go to a lot of trouble to find out what the average rider prefers, because the maker who guesses closest to the average preference gets the largest sales. But the average rider is mainly interested in silly (as opposed to useful) “goodies” to try to kid the public that he is riding a racer

  3. #3
    Join Date
    14th June 2007 - 22:39
    Bike
    Obsolete ones.
    Location
    Pigs back.
    Posts
    5,390
    Da Daa! Quick & easy, thank you.

  4. #4
    Join Date
    14th March 2007 - 20:11
    Bike
    bandit 1200s
    Location
    Hamilton
    Posts
    1,208
    question is - if you put a smaller wheel on the front of your pushbike; wouldn't it be the same as riding down hill all the time?
    Lifes Just one big ride - buckle up or hang on

  5. #5
    Join Date
    3rd March 2008 - 11:55
    Bike
    ST2 NZ250
    Location
    The evil flatlands
    Posts
    2,325
    Quote Originally Posted by smoky View Post
    question is - if you put a smaller wheel on the front of your pushbike; wouldn't it be the same as riding down hill all the time?
    Yep, if you do that you don't need to pedal any more.
    Riding cheap crappy old bikes badly since 1987

    Tagorama maps: Transalpers map first 100 tags..................Map of tags 101-200......................Latest map, tag # 201-->

  6. #6
    Join Date
    10th September 2008 - 21:23
    Bike
    Tyre Shredder
    Location
    Valley of the Sun
    Posts
    1,068
    Quote Originally Posted by neels View Post
    Yep, if you do that you don't need to pedal any more.
    Thats why I was always so fast on my "Chopper" bicycle, I always thought it was the Banana seat and pedal brake

  7. #7
    Join Date
    3rd April 2010 - 16:22
    Bike
    2000 Aprilia RSV Mille,
    Location
    ChCh
    Posts
    896
    And it you look over your shoulder you can ride 'backwards' incredibly fast

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •