Carbent Raven (Sold)

I’m pricing this Carbent Raven for a quick sale. I am the second owner of this bike. It has a fairly large frame. I would guess that it would fit a rider with 43″ to 47″ X-seam. It weighs 21 lbs with pedals. It shows that it has some miles on it but is in good mechanical and cosmetic shape. There is one exception – the carbon fiber seat has been patched on the face surface which is covered by the seat foam. (See the photo below). The seat seems structurally sounds but that hidden patch is not pretty. This bike is ready to ride today.

sold!

  • Some Details
    • FSA double crank with Q-Rings
    • Terracycle Idlers
    • SRAM chain with little elongation
    • Mavic 700c wheels and hubs
    • Bacchetta long handlebars
    • New foam seat pad
    • X-Eyed front brake, Bacchetta (?) rear brake
    • Avid brake levers
    • Shimano SPD pedals


Another Bike!

Only days after I picked up the Carbent, I noticed a posting in Craig’s List for a Bacchetta Carbon Aero for $1000. It looked to be in near new condition. I had to check it out. So, I made the trip up to San Luis Obispo and bought it on the spot. It has some pretty high end components like a carbon fiber crank, Q-Rings and a carbon fiber seat. It is pristine.

I’ve ridden both of my high racers and have decided that the Carbon Aero is staying and the Carbent will be put up for sale soon.

Getting Back On A Bicycle

It’s been a year or two since I’ve owned a recumbent bike. Recently my friend, Gregory, bought a used Carbent high racer. We get together from time to time to ride trikes or my velomobiles so I thought it would be fun to get a similar bike so that we’d have another option on our rides.

I began looking for used Bacchettas and Carbents. I even considered buying a new Schlitter Freestyle. But, since I don’t anticipate riding a bike very often, I decided to spend as little as possible. I was able to pick up this used Carbent Raven on eBay for a very low price. Carbents are built to fit the buyer. Boom length and seat recline are not very adjustable. So, I hope that I won’t need to do any surgery on this bike. I’m sure that I’ll need to refresh some parts before I take it on the road.

Update: I picked up the Carbent and it was in much better shape than I had expected. It fits me well. It will need a new chain and some cleaning but that’s about it.

Front Wheel Fairings for the DFXL

As part of the effort to help PeterB’s Battle Mountain run, we’ve been working one some front wheel fairings. These are added to the bottom of the factory pants to shield the exposed lower wheel. This has been a real challenge. The shape has to enclose the front wheels yet being wide enough to allow the wheels to travel through the steering arc. Also coming up with a shape that allows mounting to the curving bottom of the pants has been tricky. At this point, I’ve gone through three iterations of shapes. Each iteration involves building a plug, mold and part. So far, each shape has been symmetrical side to side so that I can use a single mold and trim the resulting parts to fit right or left. Before showing the evolution of shapes, here’s a photo of the latest iteration, painted and mounted on my DFXL.

The first shape that I came up with is a long teardrop shape with curved sides. The problem with this shape was that in order to open the tire slots wide enough to allow the maximum steering angle, the slots opened into the vertical part of the sides (due to the curve of the sides).

This lead to a second shape with vertical sides. This allowed plenty of room for cutting the tire slots in the bottom without the slots going up the sides. But the fairings looked massive when attached to the pants.

The third shape was based on the second but was shorter and with reduced volume.

So this is where we are right now. This 3rd iteration is smaller and there is enough room to cut the tire slots. It’s mounted with the use of magnets and tape as shown below.

However, I’m still not happy with the shape. The front seems too blunt and the tail should be elongated to make it more teardrop shaped. If I can muster the energy, I think that I’m going to modify the first shape to overcome its flaws. In the photo below, you can see the current shape in red and the first shape in white.

Oh and by the way… We have not tested the idea of adding fairings to the pants. For all we know, these things could add more drag than they’re worth. We’ll do some roll-down tests to make that determination.

“Screwless” Access Panel for the DFXL

There’s a little project for the DFXL that’s been on the back burner for a while. The front access panel on the DF is held in place by ten flat head m4 screws. I seldom need to remove that panel but when I do, it’s a bit of a nuisance. This can be particularly bothersome while out on a ride. In addition, I have to say that I find that the visible screw heads detract from the look of the DF. So this has lead to my “Screwless” access panel. There were 3 goals for the panel.

  • Be quicker to remove and re-install.
  • Give the DF a cleaner look.
  • Require no modifications to the DF body itself. The mounting system must be confined to only the panel.

Here’s the first iteration of the screwless panel. This was produced from my mold, followed by a little body work to remove the stock countersunk screw holes.

I’ve found that the addition of the NACA duct on my previous panels really made a difference when riding on warmer days. Here’s the screwless panel with a NACA duct added.

To mount the panel, I came up with a simple system of flexible tabs attached to the panel that would catch under the lip of the body. The tabs are attached to the panel using six carbon fiber slotted anchors that are epoxied to the panel.

Here’s the underside of the panel with the NACA duct and tabs installed. Different materials were used for the tabs in different locations to provide the right flexibility to allow easy installation but with a firm mount. The tabs slide into the carbon fiber slotted anchors made with a male/female squish mold. All of the tabs except the 2 rear tabs stay with the panel during installation. They’re just tucked in after the panel is in place. The 2 rear tabs are inserted after the panel is in place. It takes a few seconds to install or remove the panel. No modifications to the DF body are required.

This is the 3D printed squish mold used to produce the carbon fiber slotted anchors.

Full view of the DFXL with ducted, srcrewless access panel.

A Rear Wheel Fairing for the DFXL

I’m in the process of building some aerodynamic bits and pieces for the DF to be used by Peter Borenstadt at the Battle Mountain event coming up in September. I’ve made him a more aerodynamic hood and now I’m working on some wheel fairings to cover the exposed tires both front and rear. The front wheel fairings will be attached to the bottom of stock DF pants. The rear wheel fairing will attach to the underside of the DF. I decided to start with the rear wheel fairing.

This fairing needed to fit the contours of the underside of the DF. Rather than building the prototype of the fairing directly on the DF, I made a mold of the rear underside of the DF and made a copy from that mold to work on.

So the idea was to use the copy as the base for the plug. I would then form the fairing shape on the copy which would complete the plug. I would take a mold of the plug and I’d be ready to produce the actual part.

I designed the basic shape in Fusion 360. I translated that design to patterns to cut from a pink foam sheet using the software Slicer for Fusion 360. I then built a full scale version of that design from the foam cutouts, epoxy resin, body filler and a lot of sand paper. Next I fused the shape on to the plug base and added fillets where the vertical faces met the horizontal faces. I then made a mold of the completed plug which is the orange piece shown below.

Here as some photos of the resulting wheel fairing. The part was made with 2 layers of carbon fiber twill using the vacuum bagging technique. The final trimmed part ended up weighing 112 g.

PseudoMonster Sold

The current owner of the PseudoMonster, Stephen, has decided to part with this interesting trike. I’m handling the sale for Stephen.

Price: $1600 plus shipping to the continental U.S.A. ($150 maximum or less depending on destination)

Sold

Trice S / Vortex (AKA Pseudo Monster, AKA “Munster”)

Up for sale is a special Trice composed of selected Trice components to achieve a long, low, narrow, foldable fast trike. I am handling the sale for the owner, Stephen (BROL member “Munster”). This is the trike that Stephen has named the “Munster”. I originally built this trike and sold it to Stephen. My goal in choosing the components was to try to come up with a trike that was similar in configuration to the unobtainable Trice Monster. You can read about it here.

The heart of this trike is the Trice S cruciform. This is a hard to find part that offers the advantage of a narrow track and a stretched length compared to other Trice cruciforms. The extra length allows for more space to place the seat in a more laid back position. The rear frame member is from a 2010 Vortex. This foldable frame member will accommodate a 26″ or 700c rear wheel. The 349 front wheels and 559 rear wheel were chosen to give the trike a very low center of gravity.

I have just gone through the trike to freshen it up. I washed the seat and bags, replaced the chain, chain ring and rear shift cable. The trike is mechanically sound. It rides great. With the low center of gravity it flies around twisty turns. The frame shows its age with a fair number of scratches and scrapes. See photos below.

  • Crankset – 165mm Shimano triple (53-40-30)
  • Pedals – Crank Brothers
  • Chain – near new Wipperman Connex 9 speed
  • Front Derailleur – Shimano Triple
  • Shifters – Shimano 9 Speed Bar Ends
  • Tires – Near New Kojak 349s (front), Kojak 559 (rear)
  • Front wheels – 36 spoke 349 Velocity Aeroheat
  • Brakes – Sturmey Archer 70mm drums
  • Rear wheel – 32 spoke 559 Aeroheat with Velocity hub
  • Brake Levers – Tektro
  • Idlers – Terracycle dual idler
  • Rear Hub – Velocity with 11-32 Cassette
  • Rear Derailleur – 9 speed Shimano Deore XT long cage
  • Seat – ICE S hard shell
  • Includes modified Catrike 700 frame bags (see photos below)


Tail Extension for the DFXL

I’ve seen old photos on the internet of some custom modifications on Daniel Fenn’s DF. These mods were never made available for sale. One that looked interesting was the tail extension shown below.

A friend of mine, Doug from Riverside, recently was able to talk Daniel into selling him a couple of copies. Doug then surprised me by sending me one. I know that the extension probably wouldn’t make any speed difference for me at the speeds that I travel, but I wondered if it might improve stability in cross winds.

I’ve been working with Peter Borenstadt on a few aero pieces for his upcoming Battle Mountain run in his DF (see the “aero” hood in an earlier post). Peter had a home made tail extension so I asked him if he’d like to borrow the real thing. Of course he said yes. Before shipping it off to him, I decided to make a quick mold and copy just in case anything happened to the original. Making the mold wasn’t difficult. But it was tricky laying up the part because of its very thin trailing edge.

Here’s the original extension with temporary flanges and the resulting 2-piece mold.

To lay up the trailing edge of the part, I chopped up some carbon fiber material into short strands. I shaped a piece of wood with a skinny rounded tip that fit into the radius of the trailing edge. After applying the gel coat and letting it partially cure, I put the chopped carbon fiber along the trailing edge and up the walls a bit then tapped it into position with the stick. Then I just wet laid up 2 layers of cloth in the rest of the mold and overlapped the chop. The part turned out pretty nice with no voids but a bit heavier than the original. The original was just a single layer with no gel coat.

Here’s my copy of the tail extension, painted to match

I tried it out for the first time yesterday on a nice ride with my friend Gregory (who rode my WAW). I couldn’t feel any changes in stability nor speed. At least my red electrical tape mounting system worked as the tail didn’t fly off during the ride.