Motorized Recumbent

Discussion in 'Motorized Recumbents' started by seabillco, Jul 19, 2008.

  1. seabillco

    seabillco Member

    Hi, all
    I just finished building a motorized recumbent if anyone is interested. It's a Rans recumbent and a Ryobi 30cc weed eater engine. It has a motorcycle style 'clutch' and a brake lever for a throttle.
    It's VERY fun to ride.
    I've attached pictures.

    Steve G
    Grants Pass, Oregon

    Attached Files:

    Last edited: Jul 19, 2008

  2. vegaspaddy

    vegaspaddy Member

    congrats seabillco,

    thats a nice clean homemade friction build you have, excellent job.
  3. seabillco

    seabillco Member

    Hi, vegaspaddy!
    Thanks! I'm planning to add a bike computer soon so I can calculate top speed and MPG. I'll post it asap.

    Have a great weekend!
    Steve G
    Grants Pass, Oregon
  4. That manual clutch is simply BRILLIANT!! So just the weight of the engine is enough to give it some drive or do you have a kind of a spring to the assembly?

    And I don't see any welds. I do see stuff you find at the hardware store. I also see the use of grade 8 hardware.

    Dude. I'm copying your design on my trike.
  5. seabillco

    seabillco Member

    clutch on recumbent

    Hi, LF
    The clutch idea is based on revelstone's ride on a mountain bike:

    It works great on the recumbent. The engine weight plus a bungee cord keep the spindle on the tire. The clutch just lifts it off the tire a fraction of an inch.
    The recumbent is a blast to ride with a motor and I'd love to do a trike next.
    I think that would be the BEST for several reasons.
    The clutch isn't working as well on my mountain bike because I haven't been able to get the angles right. I'm planning to add a pulley or two to increase the force.

    Have fun!
    Steve G.
    Grants Pass, Oregon
  6. revelstone

    revelstone Member


    seabillco, thanks a bunch. having someone use your ideas and fitting them to thier own needs is a cool compliment to me. glad something i did helped someone else. bill gates could learn a few things from this site. but he'd probably claim they were intellecual ideas and charge us a fortune for them :grin::grin:
  7. seabillco

    seabillco Member

    Hi, again, LF
    Sorry, I forgot to confirm your astute observation about grade 8 hardware.
    I used AN nuts and bolts because I have a Rans S-12XL home built airplane. All the nuts and blots on this recumbent project are from leftovers from my plane. Also, my plane AND the recumbent are BOTH made by Rans.
    Also, you are correct that there is no welding.
    I'm VERY happy with the recumbent project.
    I'm eagerly waiting for a 4 stroke engine I bought on eBay to arrive so I can strap it to something around here and see what happens!

    Have fun!
    Steve G.
    Grants Pass, Oregon
  8. Seabillco,

    You just keep going and going, slow down I have yet to finish mine. :)

    Nice work.
  9. seabillco

    seabillco Member

    Next stop - 4 cycle!

    Hi, SVH
    This is just too much fun!
    My used, $50, eBay, Ryobi, 25cc, 4 stroke engine arrived today! It runs but that's all I know so far!
    I'm eager to see what it will be like on a MB.
    I'm hoping it will be more quiet, cleaner, more torque and get better gas mileage. I will weigh it to compare to the 3.75 pounds from the 31cc Ryobi 2 stroke.
    On my last trip to town and back (14 miles) on the mountain bike, I got 153 MPG.
    I just returned from a longer trip to town and back on the recumbent. As soon as the engine cools down, I'll fill 'er up and calculate mileage and post it here.
    At the moment, the recumbent is my favorite because it's so comfortable to sit in. My 50+ year old buns like that a lot!

    Have a great day!
    Steve G
    Grants Pass, Oregon
  10. seabillco

    seabillco Member

    Recumbent = 240 mpg!

    Hi all,
    I just returned from a 15 mile trip to town and back on my motorized Rans recumbent. It has a Ryobi 30cc 2 stroke engine on it.
    I filled the tank before leaving and watched my odometer and then filled the tank after I returned. I've made the trip before so I know the mileage is correct.
    It took slightly less than 1 cup to fill the tank! There are 16 cups in a gallon. So, the gas mileage was slightly better than 240 mpg (16 x 15 = 240).
    While that's amazing, I need to point out that I did some riding with the engine off while in town. I'd estimate I rode, at most, a total of 2 miles without the engine running. In that case, the mileage is 208 mpg (16 x 13 = 208).
    No matter how you slice it, I'm getting better than 200 mpg with this recumbent/Ryobi combo. I find that amazing!
    I'd love to hear from anyone if they find a flaw in my method or if they have any experience with the mileage using these engines. Maybe I'm dreaming here and need a wake up call...
    The last time I rode the mountain bike into town and back, I got 153 mpg. The recumbent is probably more aerodynamic than the mountain bike and perhaps this "SS30" engine is more efficient than the 31cc version.

    Steve G.
    Grants Pass, Oregon
  11. seabillco

    seabillco Member

    4 stroke on recumbent

    Hi, all
    If anyone's still reading, I received the Ryobi 26.2 cc 4 stroke engine yesterday and installed it on the recumbent.
    I ran a test today and it got 231 mpg.
    So, it's about the same as the 2 stroke 31cc Ryobi.
    But, the 4 stroke is MUCH quieter and a real joy to ride. It also has a little more torque but a little less horse power. So, it goes up hills a little better and is a little slower at top speed (25 mph v. 30 mph).
    Overall, I must prefer the 4 stroke and will keep that on for now.

    Have fun!
    Steve G.
    Grants Pass, Oregon
  12. seabillco

    seabillco Member

    I switched to the Ryobi 26.2cc 4 stroke engine and love it! It's VERY quiet and smooth and has a little more torque but a little less top end. It gets about 230 mpg.
    I will stick with this set up for now since the new engine is such a dream to run.

    Steve G.
    Grants Pass, Oregon
  13. pumpbuilder

    pumpbuilder Member

    Yeah I love mine also, and your right the forums could use a section just for recumbents. Did the search found this, you should change to the urethane drive roller, much better for the tires.
  14. seabillco

    seabillco Member

    Hi, pumpbuilder
    Thanks for the support!
    Can you help me locate a suitable urethane drive roller?
    I have a 3/8" crank shaft that's threaded with 24T threads. Currently, I screw a BMX footpeg onto the crank.

    Thanks again!
    Steve G
    Grants Pass, Oregon
  15. pumpbuilder

    pumpbuilder Member is who I get everything from. If you decide to get a commercial kit get one from these guys, I have been running on their kits since 93. They have kits for recumbents and built this one for me.
  16. seabillco

    seabillco Member

    Hi, PB
    Thanks again! I've looked at their kits and have definitely considered it.
    I was shopping for a used motor of the type they recommend and almost got one the other day but I was too late. It was sold.
    So, once I get a suitable engine, I think I'll get a kit, especially now that I know the friction drive will actually work in the rain! I didn't know that before.
    I noticed you've been using their kits since 1993. Man, that's quite a testimonial. They might want to use YOU in their marketing!
    It's weird that there seems to be some resistance to a recumbent section. I hope that will be reconsidered since they truly do have unique issues and, while they are not nearly as common as other styles of bikes, those of us who ride them could really help each other out a lot more if we knew who we were and where to go for advice and ideas.
    So, again, thanks for the support!

    Have a great weekend!
    Steve G.
    Grants Pass, Oregon
  17. pumpbuilder

    pumpbuilder Member

    Yeah its been funny how the belt & Chain folks beat up friction drives about wet weather and I don't know why more folks don't talk about his all weather drive roller but.... my daughter even used it in the snow once. I worry more about the strain on spokes[Belt Drive] causing a catastrophic failure at speed from a hard bump. Worst thing that ever happened to me was a cable broke once when I did not maitain it properly so I had just pedal power home but with the standard, non clutch model like I use there is no drag on the system when not in use so its just the extra 11 lbs to slow you down. The cable issue is gone now as he improved that part years ago. His maple drive rollers are fine as well but I like the eurathane because they look good. Lets face it, on the recumbent your styling, lol.
    Last edited: Jul 31, 2008
  18. srdavo

    srdavo Active Member

    hi guys.... thought I'd jump right in here.....
    I like friction drive....I have 2 bikes ,set up homebuilt. I have not had any tire issues.

    I have a bikeE.
    It rides soooo comfy!
    I want to motorize it....bad!
    (I just don't want to mess up this cool bike)

    there must be 3 of us bent riders now...hehehe.
    I'm not seeing any resistance to a recumbent section. (Our admins are on vacation.)

    this thread is a good place to start.
    you guys can talk me into motoring up my bent.
  19. seabillco

    seabillco Member

    Have you any idea of the 'ideal' tire pressure for your friction drive recumbent?
    I've done some experimenting with my Rans Tailwind recumbent and notice that the rear ends seems to fishtail easily when the tire pressure is a little low.
    But, at the same time, I notice that the friction drive seems to do a little better at gripping the tire when the pressure is a little low.

    Steve G.
    Grants Pass, Oregon
  20. seabillco

    seabillco Member

    Howdy srdavo,
    Thanks for joining us. Three Amigos!
    The 'resistance' comment relates to the suggestion I made for a separate section for recumbent issues being met with a very brief reply to 'do a search'. It's hard to take that as enthusiasm! Perhaps 'resistance' was too strong a word...
    I was VERY careful when I motorized my $995 Rans Tailwind recently. I just taped everything and did not drill or change anything permanently. It was not a problem. I LOVE my MB recumbent!
    IMHO, it's WELL worth doing since it's so comfortable!

    Have fun!
    Steve G.
    Grants Pass, Oregon