Re-use rack mount engine?

Discussion in 'Rack Mounted Engines' started by MotorbikeMike, Oct 14, 2013.

  1. MotorbikeMike

    MotorbikeMike Member

    Hi all, I was just wondering IF there was an in-frame solution that could re-use Honda gx35, Robin Subaru 35, Dax XC35, and also the Hua Sheng 35cc, would anyone be interested?
    IF the Tanaka, or other quality 2-strokes used the same clutch pattern (special bolts at certain distance) then it would seem that they might be adaptable to an in-frame style also.

    I have ridden the Honda, and the Robin Subaru, I found them to run real nice, BUT I am a big guy, and that was not helping the smaller engine, especially on hills.

    Let me know what you-all think,


    MotorBicycleRacing likes this.

  2. 5-7HEAVEN

    5-7HEAVEN Active Member

    I'd be interested, if I can keep gearing low enough to use my 8-speed cassette.
  3. MotorbikeMike

    MotorbikeMike Member

    Hi thanks for responding! I had not considered gearing, as I have not needed it on the 49cc. I realize there is a major difference in Torque on the smaller engines, but I was planning to add flywheel action into the mix to increase torque, and to temper the natural drop in power you get putting a load on a small engine that does not have a lot of flywheel action.
    This is not to say that a shifter would not be a possible addition, where desired.

  4. butterbean

    butterbean Well-Known Member

    If you can be precise enough, just drill the kit mounting plate to accomodate the smaller engines. As long as the bolt patterns are far enough apart to leave enough material between the old holes and the new ones, should be fine. A few guys have re-drilled the kit plates to mount 79cc Predators, I'm sure it can work the other way, unless the bolt patterns of the 35cc or whatever and the 49cc are too close together. Should be able to hook a shift kit right up with the kit mounting plate. One guy even has the same engine I do, 98cc side valve, with an agk Predator mount and agk jackshaft, hooked up to a shift kit and the shift kit acts as a 3rd motor mount. Some of this stuff is basically going to come down to fab skills for the end user.
  5. butterbean

    butterbean Well-Known Member

    In fact, thats something a lot of people could do themselves if they have a drill press and something to measure precise distances with, without paying extra for an enhanced kit. Want to mount an FD engine in-frame? Just buy the kit and spend another $30 for a kit mounting plate, and drill the necessary holes. Of course, there will be those few who dont have a drill press or the fab skills to do it correctly. I suppose that's the market you're looking for, but are there enough people who want to mount a rack-mount in-frame that cant do it themselves to even make a market? Perhaps, perhaps not. I probably couldn't do it myself, but I dont want anything smaller than 49cc anyway. I'm not trying to be negative, just playing devil's advocate. I have not heard of or seen very many people attempting to mount such a small engine in-frame. I suppose from a legal standpoint, it does fall way under some state's legal requirement of 49cc or less, and open up the option of a shift kit, but then again the 49cc engines themselves already fall below that requirement, and are already shift-kit ready without too much fussing around. Here in PA, the only distinction between 49cc and above is that anything 49cc or less is a moped requiring registration and a driver's license, while anything above is a motorcycle. I choose not to register, and the police do not bother me where I live. And comparing a 49cc with a shift kit to a 35cc with the same gearing, the 35cc is still going to have much less power. So is it worth the extra money for an enhanced kit, plus a shift kit, for probably about 20% less power? Some might think so, others might not. Again, not being negative, just playing devil's advocate. If I were a businessman/product developer, I'd want to know there was a MAJOR market for a product before I'd even think about R&D, but that's just me. No point in wasting time or money on something people won't buy.
  6. MotorbikeMike

    MotorbikeMike Member

    Hi Butterbean, there are several states with 32-35 cc regs, AND, I am fishing to find out what engines people have, and like. I have Whizzer, Hau Sheng, and currently have a 9 cu inch Briggs and Stratton engine. I own a Robin Subaru 35cc, a 49 cc Royobi 4-stroke and a bunch of other stuff.

    I recently sold off HF 79 and 99, didn't need them. We are capable of making a good engine run well in a bike.

    As a side note, Id sure like to know what engines people have and like?

  7. butterbean

    butterbean Well-Known Member

    I have a Lifan side-valve 98cc minibike engine, and I absolutely love it. Geared 12.44:1, she will do 30 easy and climb walls with proper clutch adjustment. I'm 300 lbs, so its either get an engine with the power to drag my big butt around, or get a shift kit. Didnt feel like fooling with the shift kit, so bigger engine it was. My bike is custom in just about every way. I built it from the bare frame up, piece by piece, with parts I picked myself. Its not a kit build at all. Only kit part on the entire bike is the throttle, grips and killswitch. I did have some help from my good buddy jbcruisin, and actually built the bike in his garage. I love the bike and the engine, and plan on keeping it on the road for years to come. You hear some older guys talk about how they wish they never would have sold their norton or their triumph, but they had to grow up and start a family or yadda yadda yadda. This is my norton (so to speak) and thankfully I'll never have to live with the regret of selling it.
  8. grinningremlin

    grinningremlin Active Member

    I've heard reference to it a while back, but it ended up going nowhere (no demand?) scooterguy I believe had something in the works.I'm a die-hard rack-mount guy, personally don't see the appeal of a framer, but to each their own.I think you'll be surprised if you can figure it out, remember Robin-Subaru/Mitsubishi/Tanaka are all high tech goers.A TLE43 has 2.2 HP, a Chinese copy 43cc has 1.6 HP.Lighter engine with the same power=same or better pull with probable better mileage.Bikes work best with the lightest load possible, my EHO35 on a 20lb mountain bike pulls fine, on my 40lb recumbent it struggles up hills.
  9. MotorbikeMike

    MotorbikeMike Member

    Hi all, we shall see what develops? To Butterbean, Next time you see or talk to Jay Cruise, you ask him about a California Motorized Bicycle guy named Mike Simpson, AKA Rednecktele, he MIGHT remember me?
    I have no fear about successfully outfitting the little 4-strokes, we already own a running gx35 and a RS EHO35.
    At around 300 lbs I have ridden Robin, and Honda minis, and they actually worked ok, we just want top make it better!
  10. 5-7HEAVEN

    5-7HEAVEN Active Member

    As I type, I rest my other arm lovingly on my Scooterguy-mounted Tanaka engined motorized bicycle. It is a much better-balanced MB than the Mitsubishi- powered Staton/NuVinci driven Trek I'm reassembling.
  11. MotorbikeMike

    MotorbikeMike Member

    Well, information is starting to drift in! What kind of speed and climbing performance do you get from the 35's? Do any of you have the 49cc HS or Honda AND a 35, or ride with them?
    What do you think the loss is, with the reduced power, 20 per cent?

  12. dchevygod

    dchevygod Member

    I have a Zenoah G43 " the original 43cc for goped " at the moment and its peppy enough, and with the stock can its very quiet but can't use the full potential of my race porting. My current left side drive setup won't allow use of my FLOWSYSTEM pipe made for this motor :( so I'm re-thinking my drive setup to go back to the GEBE style belt and more of a solid weld on rack/motor mount plate. I had a cy460 on this drive initally and tore up the frame the mount plate was designed for so it got swapped to my cheapy freebie next Avalon bike and it was an awesome ride till I was offered my current motor "just re topped and ported" with the flow pipe"that's needing a repair" for my used motor. It came off of a goped GSR and I do have one but this is a known reliable power plant so I may put this on my ped or redesign my mb.