S40 Gen6 seat adjustment

[Laidbackladdie]

I’ve now ridden a couple of hundred miles on my S40 and the various adjustments seem to be optimised except that I feel that I’m slipping down / forward a little towards the tip of the front of the seat. I regularly just sit up / push back on the pedals to plant my butt and back firmly in the contours of the seat. I’m built fairly close to the ground at 5’6” (167cm) tall with an inside leg of around 30” (78cm). It’s not a hugh problem or inconvenience but I’m just wondering if there’s anything I’m not doing or have set up incorrectly? I have placed two shims under the tip of the seat to increase the standoff from the frame by about 3/8th” (10mm) and that has helped but not solved it. Any advice would be appreciated. Thanks.

 

[Always-Learnin]

Some have added 1-1.5 inches of padding to the front of the ventist pad. You can open it up, add the padding and use zip ties to close.

 

[LarryOz]

I fabricated a lumbar support and taped it to the seat - this also helps a little with slippage - but if you find you are really slipping all the time you might have your BB out a little too far and as you are "reaching to pedal" you might be pulling yourself down via your pedal stroke. I would suggest experimenting by pulling your BB in about an inch and see if that helps some. What you don't want to do is pull it in too much where you knee if really bent a lot on the backstroke (a shorter BB can correct this too) - but knee pain will let you know if this is happening.

 

[Boreen bimbler]

I just 80% solved this problem (ventisit pad) by moving the pad forward on the seat. So it's actually overhanging the front of the seat a little.

 

[Laidbackladdie]

I fabricated a lumbar support and taped it to the seat - this also helps a little with slippage - but if you find you are really slipping all the time you might have your BB out a little too far and as you are "reaching to pedal" you might be pulling yourself down via your pedal stroke. I would suggest experimenting by pulling your BB in about an inch and see if that helps some. What you don't want to do is pull it in too much where you knee if really bent a lot on the backstroke (a shorter BB can correct this too) - but knee pain will let you know if this is happening.

Thanks Larry Oz, last week I tinkered with some refinements on my set up and placed a thinner pad under the seat cushion. I did a 100mile event last night and whilst I still had a little slippage I can live with it. I’ll continue to make one change at a time. I was able average 14.3mph on a route t with over 3,000ft elevation gain so that’s not too shabby at this stage. I do have 155mm cranks btw.

 

[smarkberry]

I’ve now ridden a couple of hundred miles on my S40 and the various adjustments seem to be optimised except that I feel that I’m slipping down / forward a little towards the tip of the front of the seat. I regularly just sit up / push back on the pedals to plant my butt and back firmly in the contours of the seat. I’m built fairly close to the ground at 5’6” (167cm) tall with an inside leg of around 30” (78cm). It’s not a hugh problem or inconvenience but I’m just wondering if there’s anything I’m not doing or have set up incorrectly? I have placed two shims under the tip of the seat to increase the standoff from the frame by about 3/8th” (10mm) and that has helped but not solved it. Any advice would be appreciated. Thanks.

I’ve had the same issue. Here’s what I found on ChatGPT. I purchased a foam block from a local hobby store and will use an electric knife to shape the insert.

 

[Laidbackladdie]

I’ve had the same issue and solved it in a similar manner. I tried a number of solutions but have settled for a shaped firm pad right on the ‘nose’ of the cushion between the existing pad and the cushion cover. I also added a small piece of padding right where the lowest past of my backbone touches the cushion pad - I used a piece of pressure relieving padding, the sort used on wheelchair cushions for this backbone pad. This combination works for me and I had no issues recently on an 8 day touring trip. You might just notice the changed geometry of the seat pad in the photo.