FireBelly 4 Stroke "Hard Box" Transmission

Discussion in 'Dealer Advertisements' started by FireBellyCycles, Mar 30, 2009.

  1. We have been testing our own transmission design with what we believe to be "Great success".

    It is chain/sprocket drive and utilizes a Max Torque centrifugal clutch. w/ current reduction and standard 44 tooth final drive it produces a top speed of 33 mph. Reduction can be changed w/ off the shelf parts as well as final drive sprockets. It is narrower than the Hoot and Grubee as a prototype and will be even narrower in production.

    All metal in construction, w/ aluminum covers, it will prove to accent the look of vintage style bikes as well as new models.

    It is set to go into production in the next couple of weeks w/ availability beginning (most likely) in late April. Transmissions will be available in a complete kit or seperately (for those who already own a kit w/ an inferior transmission) and will be available for models w/ 15mm, 5/8", or 3/4" shafts.

    Retail price will depend entirely on production costs but it is our intention to keep quality and appearance high and price low! The kit will come w/ a "real" universal engine mount that will also look nice.

    The current pics are of the prototype (built for functionality only) and the finished product will be cnc precision machined to a more rounded shape reminiscent of vintage single cylinder motorcycles.

    I'll post pics of the finished product as soon as I can! I'm confident that it's appearance and funcionality will appeal to the asthetically minded m/b builder.

    As always "Motorized Bicycles and Accessories Built for the Real World"

    Attached Files:

  2. Ghost0

    Ghost0 Guest

    I like the fact that it is narrower, the clutch is in the open for better cooling and I bet the chain drive produces a significantly quieter box than the Hoot or Grubee.
  3. Skyliner70cc

    Skyliner70cc Active Member

    Very nice. Sounds like a great option out there than the noisy gear boxes.
  4. Cool! thanks guys, all is going well! Quiet, reliable and powerful!
  5. duivendyk

    duivendyk Guest

    Is there a primary chain drive between the crankshaft and the clutch?
  6. Yes, there is.
  7. wcocc

    wcocc Guest

    how much for the drivetrain? will it fit the stock honda gx50 motor ?
    let me know soon, I will be needing a tranny asap.
    IE: willing to prepurchase via paypal too.
  8. duivendyk

    duivendyk Guest

    So there are actually three chains involved in this drive train ,a primary from engine to clutch,then one between clutch out, and output sprocket and then a final drive to the rear wheel.No quick change of the drive ratio is posible,except possibly with an internally geared hub.
  9. You will be able to change the ratio in very little time! But you are correct that it is not designed to be constantly changing the gear ratios. I've ridden all over Seattle w/ the ratio that I have right now and it goes up and down hills (and we have hills) with ease and a top speed of 34mph. I think most riders will pick a ratio that works for their geography and stick w/ it.

    Just to be clear that's 2 chains transmission and 1 chain final drive. It is not much different than that of a go kart set up. Simple and Strong!
    Last edited: Apr 6, 2009
  10. DetonatorTuning

    DetonatorTuning Active Member

    what's the max amount of reduction you foresee possible at the output shaft ?

  11. wcocc

    wcocc Guest

    whats the reduction? is the max torque clutch springs stronger to engage at the higher rpm idle? I know that when I stuck a maxtorque clutch on my honda gx 50, it would not stop engaging, the idle was just too high for the standard 3600 rpm clutches. Are the clutches upgraded?
    let me know if so, and pricing, availability etc.

  12. duivendyk

    duivendyk Guest

    If you have enough displacement,are not over-geared and the hills are not too long I suppose you can make do without a transmision.I thought for a moment you were copying the Frazer Nash multiple chain drive (using dog clutches) of the 20's. My grandfather had one of those sportscars.It was very light (no driveshaft& differential)and you could change gears very quickly.Regrettably it did not survive WW2.
  13. Around 7:1 total reduction. It is currently at 3.64:1 and produces the previously stated top speed of 34mph w/ a 10 tooth drive sprocket and 44 tooth wheel sprocket and 26x1 1/4" tires.

    You can fit an 11 or 9 tooth drive sprocket for a quick 10% adjustment either way. There is room for adjustment at the primary and the secondary for ratio change as well. Though less at the primary because of clutch engagement speed.

    Until Next Time WOT
  14. The clutch engages at 2000-2200 rpm and the motor idles at about 2600 rpm, so the clutch is on the 1st reduction shaft.
  15. duivendyk

    duivendyk Guest

    I am confused,a total reduction of 7:1 of the entire drive train?,that cannot be.You have a 3.64 reduction presumably of the transmision by itself,combined with 4.4:1 in the final drive this produces an overal ratio of 4.4x 3.64=16. That's more like it.
  16. DetonatorTuning

    DetonatorTuning Active Member

    i'd need more like 7:1 out of the tranny so i could put 2.8:1 behind it with SMALL sprockets for about 19.63:1 total.
  17. Sorry I was not clear I was answering detonatortuning's question about total possible reduction on the transmission alone. It is about 7:1.

    There are many different bikes, trikes etc and jackshafts and this transmission is designed to be adaptable to many applications. Therefore an o/a wide reduction range needs to be possible.

    That said a 7:1 transmission will have different clutch springs than a 3.64:1.

    Higher than 3.64:1 is easilly accomplished as well. For most people's application there is plenty of ratio options w/ a standard clutch (2200 rpm).
    for the special large reduction applications a lower rpm clutch (1200 rpm) will be furnished.
  18. So the redesign has been submitted. The tested dimensions and layout remain the same however the 1st reduction will now be sealed and bathe in oil. This will improve appearance, insure quieter operation and longer chain life. Weight is expected to be in the area of 7 lbs.

    We believe that w/ the weight and drive train resistance down to a minimum and optimal gearing ratios that this is a top notch option for the 4 stroke motor kits. We also believe that appearance and craftsmanship are an integral part of the motorized bicycle experience. We have designed this transmission to complement the appearance of your vintage and modern rides alike. All of the machining and labor are and will continue to be performed in America; all parts and materials are sourced from American companies. Every effort is being made to keep cost down while operating w/ ethic and integrity. This will not be the cheapest option but we hope that the price to value ratio will provide you w/ the best transmission available. We are open to any questions comments or concerns.
  19. Updates!

    FireBelly's new 4 stroke drive solution is going into production. Only a very limited # will be available for purchase initially.
    Some of the features include:

    CNC machined Aluminum; All hard parts!

    Lighter Weight

    Outboard Bearing Support for engine output shaft

    Sealed Bearings

    Quiet Operation/Minimal Maintenance; Closed and Sealed 1st reduction chain bathes in oil.

    Many Gear Ratio Options!

    Cool Clutch Operation for longer life.

    Made and sourced locally in WA and the greater U S of A

    We Think it is Simple and Ellegant!
  20. fetor56

    fetor56 Guest

    FireBelly....can u tell us anymore about it(together with rescent pic) many are going to be produced & at what price?
    Any added info would be handy,thanks man.