stuckonbents
04-12-05, 08:26 PM
If you ride a bike with a straight seat back, will you will get recumbent butt as they say? Is it because of the straight seat back?
TIA,
Stuck.
megaman
04-12-05, 11:42 PM
My seat back is pretty upright. I've never had any soreness of any kind.
stuckonbents
04-13-05, 12:45 AM
My seat back is pretty upright. I've never had any soreness of any kind.
What type/model 'bent do you have and how long of a ride do you go for?
johntolhurst
04-13-05, 12:55 AM
From what I've been able to figure out, recumbent butt is due to a lack of circulation caused by sitting on a flat support. When I use a cupped shape to sit on I dont get this. Maybe with a low angled back there is so much less weight on your butt that it doesn't need a cupped shape under it?
When you say straight back - maybe you mean a seat back that has no shaping for lumbar support? This kind of seat also gives me recumbent butt. In this case what seems to be happening is that the pelvis rotates back too far and so you are not sitting properly on your buns.
Hope that helps a bit.
'95 torp; '05 cruzbike
bentcruiser
04-13-05, 07:07 AM
If you ride a bike with a straight seat back, will you will get recumbent butt as they say? Is it because of the straight seat back?
No. It has a lot to do with the seat base as well. If you sit straight up, you had better have a good seat base like a RANS or Bacchetta or Easy Racers seat base. Otherwise, you get recumbutt.
megaman
04-13-05, 10:22 AM
What type/model 'bent do you have and how long of a ride do you go for?
I ride an EZ Sport. This is the third season I've had it. My ride averages are variable, but by mid season I'll ride over 40 miles. Last year my longest ride was 67 miles. Hoping to do a century this year.
stuckonbents
04-13-05, 11:22 AM
When you say straight back - maybe you mean a seat back that has no shaping for lumbar support? This kind of seat also gives me recumbent butt. In this case what seems to be happening is that the pelvis rotates back too far and so you are not sitting properly on your buns.
Here's an example of what I'm talking about: http://www.easyracers.com/ez_1_sc.htm
Contrast that with this: http://www.ransbikes.com/2005bikes/Rocket.htm
Stuck.
If you ride a bike with a straight seat back, will you will get recumbent butt as they say?
I took out a Bacchetta Giro 20 for a long, hilly test ride (52-mile RT commute) last year. LBS had set the seat fairly upright, since I was/am a 'bent newbie. Got severe recumbutt starting around 15 miles in, basically toughed it out. Before leaving work, reclined the seat two holes. Rode all the way home, no recumbutt. See the last paragraph for how this relates to your decision-making process.
BTW, saw your other post re: SWB/high-BB bikes in traffic. I haven't found it an issue - all my testrides have been on high-BB, SWB bikes in Seattle-area traffic, a mix of door-zone marked bike lane, MUP, busy urban streets and generous shoulder with marked bike lane. Bikes range from HPVelo SpeedMachine (16" seat, 25" BB, extremely laid back) to Rans Force 5 (dual-650c highracer) at the extremes. Only the SpeedMachine was at all hard to ride, and it was still quite manageable - I got on it for the first time around sundown, and rode it home over a rather hilly route in the dark, clipped in, without scuffing either bike or rider. The highracer was actually the most stable at low speed - others have observed that the larger wheels seem to contribute to this. My X-seam is only 40", so I'm not long-legged at all. My new Tiger (rotatorrecumbent.com) is due in a couple weeks (fingers crossed) - it's a high-BB, dual-20", SWB with a huge gear range and disk brakes for the hills and rain.
As always, YMMV, so take some *long* rides. I put in over 150 miles of test rides, most of it on the four bikes above, before I made up my mind. If your body will let you ride for an hour, ride for an hour. If you're going to need to ride hills, ride hills. Same goes for traffic. Then come back in a week and do it again on another bike. If you have them and are used to them, bring your clipless pedals and shoes - they make a huge difference to me on high-BB bikes. The good shops will be happy to have you do this - you don't want to buy from the other ones anyway!
Good luck and have fun,
John