Page 4 of 4 FirstFirst 1234
Results 31 to 36 of 36

Thread: 24 to 25" rear wheels make chair tippier?

  1. #31
    Quote Originally Posted by rlmtrhmiles View Post
    rollin..move your head I and guarantee your COG will change.
    lol, i gotcha.

    height and width are not a problem. i only got 2 degree camber and my fsh is only 18.5. i had 20" on my old chair and there were only minimal things my knees would hit. guess the transferring is my only worry then.

  2. #32
    Senior Member
    Join Date
    Aug 2012
    Location
    Pennsylvania
    Posts
    1,813
    SuperSi...try sit far enough, near edge of your seat and with you body and arms in correct position, I bet you can tip your chair over far faster than your body can recover from that COG change. I've done it 2X on new chair in less than 1 week. First time it happenedd I did not know what the hell happened. 2nd time was not too long after 1st and finally realized what going on. Your COG is a measurment based on your position to the center of the Earth.

  3. #33
    Senior Member SuprSi's Avatar
    Join Date
    Jan 2012
    Location
    Southampton UK
    Posts
    477
    For some reason most wheelchair manufacturers do the measurement wrong. The cog for wheelchairs is actually how far forward the axle is from the backrest. So it's not truly your 'centre of gravity'. And this is irrelevant to this discussion. Rollin has stated he wants a 2" cog, which will be the same regardless of what size wheels he specs.

    Miles, we're not talking about tippyness forward, when people talk about tippyness it's generally backwards. And still, having larger rear wheels on a new chair designed for them will not change how tippy the chair is forward or back. It will only effect your pushing geometry and how high you have to lift your butt to transfer.

    edit: I think I understand what's happening with you.. so let me just see if I understand you right, when you sit at the front edge of your seat, the chair is tipping forward? If so thats because your weight is too close to where the casters are. We were taught in rehab to park with the casters facing forward to give you more stability. The way I transfer this doesn't matter to me, but it might help you out.
    Last edited by SuprSi; 12-15-2012 at 07:21 PM.
    T11 Asia A after near-fatal bike crash.. Just happy to still be here

    No, I didn't loose my mind... It got scared and ran away!!

  4. #34
    they taught us the same. it don't tip when i transfer but i have been leaning down to pick up something and tipped forward.

  5. #35
    Quote Originally Posted by rollin64 View Post
    they taught us the same. it don't tip when i transfer but i have been leaning down to pick up something and tipped forward.
    Maybe you should consider adding 1'' to your frame depth to avoid this.

  6. #36
    Quote Originally Posted by Big View Post
    Maybe you should consider adding 1'' to your frame depth to avoid this.
    you're absolutely right. i have a 17" deep chair and don't have that problem at all. i'm wanting my new chair to be short as possible. i'm going 16" with 1/2" longer frame in hopes it'll be pretty stable, plus 80 degree frnt angle.

Similar Threads

  1. Need Rear wheels
    By ChrissyOT in forum Equipment & Services
    Replies: 0
    Last Post: 08-20-2012, 06:34 PM
  2. 25" Rear Wheels
    By Jimbo999 in forum Equipment
    Replies: 7
    Last Post: 01-23-2011, 08:45 AM
  3. 24" rear wheels to 25"
    By Appo in forum Equipment
    Replies: 2
    Last Post: 09-09-2010, 08:33 PM
  4. Rear wheels, what is best?
    By november in forum Equipment
    Replies: 13
    Last Post: 06-24-2008, 12:38 AM
  5. Tippier chair?
    By smokey in forum Equipment
    Replies: 11
    Last Post: 07-06-2005, 08:23 AM

Posting Permissions

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