There has been some discussion regarding carbon seat issues. I had mentioned my RailGun seat a couple of months ago and how the nose is designed to prevent hamstring damage at low seat angles.
 
I have a couple of pictures of a CA2 and an F5 with seats on them now. I should have a better picture of the F5 before long. Both os these seats were specially reinforced for big guys. Both had broken their carbon seats and requested I make a custom seat for them. Both seats are several times stronger than the typical M5-type seat design and are far more aerodynamic and at very little weight cost.
 
I also have some pictures of the new seat for my M5 that fits right down on and bolts directly to the frame. It's been a new experience even for me. The additional rigidity completely changes how the bike climbs. The M5 already is a fast climbing bike but the new seat drastically reduces the effort level (from my perspective) when climbing. It is also very, very aerodynamically efficient, according to my power meter and (everyone trying to hang on my wheel).
 
http://synthetictransport.com/railgun/
 
I'm not actually trying to drum up business here as I'm backordered and it is a lot of effort to build these things. I'm actually more interested in getting better seat design ideas started. The current crop of options for carbon seats is, imo, fairly poor. We need better.

The F5 rider didn't want a tailbox.
 
The seats themselves are all made on the same mold so the shape is identical. It's the rib that is customized for different mounting arrangements and rider situations. The F5 seat is more upright because the rider's x-seam is so long the seat rides right up against the tire even when fairly upright. Not many options there, though he ordered another seat for his second F5 and I'll be trying out a slightly different rib design on it to allow him to drop the seat back a bit.
 
Having a single rib is far less convenient for mounting on different types of bikes, especially given that most mounts are designed for the std double rib carbon seat. The greatly improved aerodynamics of the single rib seat are the reason I went with it. I don't like posting power/speed numbers on a public forum but I can tell you that nothing else is even close.
 
The seat shape is designed for power. Everyone who rides it and goes back to a std carbon seat says the std seats feel like a wet noodle. They didn't realize how inefficient the std carbon seats were at transferring power to the frame.
 
So... How about some more great ideas for improving the performance levels of our favorite recumbent bikes?

I have no idea. :^)  I expect it has the same mounting system. Is that correct? The RANS front bracket improves the stability of normal carbon seats but is more of a liability for Railgun seats and gets in the way a bit. For the F5 I basically chopped off the rib towards the nose and added a thick mounting pad for that bracket. The shape of the nose requires the use of the forward mounting pins on the plastic clamp to provide clearance for the bracket bolts.

The single rib appears to match the M5 frame like a puzzle piece. The rib fills in under the seat. Is there anyway to easily shield the open area above the front wheel?
 

 

Quote from Rat Rider on Dec 13^th, 2013, 10:48pm:

I build laminate sheets for the (multiple) ribs and then cut them out to the required shape.There is a strip of 2" wide Velcro between the rib and the frame placed to protect the frame from any incidental rubbing, etc. though it only normally contacts the two mounting areas. It would be nice if the headset could be lowered on the M5 to bring it closer to the tire. Would bring the crankset closer to the tire also, which wouldn't be good though. The open areas could be filled with a splitter. I don't know how that would be handled by the rules for unfaired bikes though. The Apache uses a splitter but again, I don't know what class they allow that bike in.

Quote from Bud_Bent on Dec 14^th, 2013, 5:20pm:

Thank you. I will say that it really has been a community effort. There have been a number of people who conspired with me to push the boundaries of how to deal with low seatback angles and even that wouldn't have happened without the general support and encouragement of just a lot of people pushing me to ride and race. A number of those people are rbent members and I thank you. I'm not making these seats to sell them. I really started doing it just to fix my problems. the first few seats were design experiments and pretty rough, but served their instructional purpose.
 
I'm currently only making them for people with various problems that can't (or can't easily) be solved with what else is out there. 30-some odd years of r&d has shown me that it is very important to discover the boundary conditions early on, and the seats I'm making for big and/or hefty riders that overwhelm standard carbon seats are certainly boundary conditions that so far I've dealt with, and their riders have been delighted because the seats not only survive them but they get to go noticably faster also! I really get a kick out it.
 
I'll be making seats for normal people soon. I have a few special people waiting in line for one and hope they don't have to wait too long. It takes an amazing amount of time, expense and effort to fabricate these things.
 
However, this community should feel proud to have helped these guys out, and I sure hope more will come of it. Five years ago it would never have crossed my mind to build c.f. bike parts and now I'm doing it!
 
Don't let life stop you from doing things that you should be doing and having fun doing! Just figure out a way to do it and when you need it, ask for help from your friends. I think they'll love being a part of what can happen.
 
Thanks Again!

The new pic of the F5 is only marginally better than the first. Is that guy riding an XL frame? He is so far over the back wheel, it must be be a pretty squirrelly steering beast.  
 
The seat on the M5 reminds me of why I have gravitated to each iteration; the shoulder area is very wide. I gotta think it is one comfortable seat.

Those aren't seats, they're beds.