Proposed build using a WM Schwinn and Tanaka 32cc

Discussion in 'Friction Drive' started by Crosshair_84, Oct 9, 2011.

  1. Crosshair_84

    Crosshair_84 Member

    I'm looking to build my first motorized bike setup. I already own two moped's;:scooter: a 1982 Honda PA50II that will carry my 250 lb butt at 30 mph top. I also have a 1978 Honda NC50 Express which can only haul me around at 18 mph top. (Not bad for vehicles with a max rider weight of 180 pounds,.) While I like both of them I am now looking for something that is 3rd world simple, yet functional. Finding parts for both of my mopeds can be a real pain at times depending on what you need to replace, thus my desire do go into the direction of simple.

    My original plan was to rebuild my busted up NC50 with a chain drive kit, but I just now bought another NC50 that runs very well so the busted up one will be used for parts instead. So the plan now is to get a bicycle and put a friction drive kit on it, since friction drive is as simple as you can get. Not to mention that if I trash the bike I can unbolt the kit and slap it on another bike easily.

    So I am set on a friction drive kit. I'm going to go for a multi-speed bike after reading around here and finding that having some gears is best. Only thing is that I haven't bought a new bike since I was 5 year old, every bike since then has been bought at a police auction or garage sale.:uhoh2: So while I think I've found a good candidate, I'll want to ask your advice on that and a few other things.

    First off on me and where I live: I am a heavily built guy and I weigh about 250 pounds. I live in Grand Forks, ND, the nearest hill worth mentioning, not counting golf courses, is 20 miles away. So I have no hills, but I do have weight. That will come in when we get to the drive rollers.

    For engine, that is already decided. I picked up one of the Tanaka 32cc 2-stroke engines that are/were on Amazon for $99. I have experience with the 2 strokes with my mopeds and prefer them to 4 stroke engines in such applications, so no need to debate that point. I might add some performance parts later.

    Now onto the bikes, the two that I have figured would be a good candidates are:
    26'' Men's Schwinn Point Beach Cruiser
    Schwinn Clairmont 26" Men's Cruiser

    Both have 7 speeds so I can help the engine out if/when needed. It already has brakes ready to go I don't need to try and add them to a coaster only bike and I will be able to easily upgrade them if I choose.

    I am not sure of the difference between them that warrants the $20 price difference. I know I will have to ditch the cargo rack on both, I could give it to my mom or dad for their bike, and I may try to mod the rear fender so I can keep some of the tire covered. Or I may just have to ditch the whole rear fender. I like the color and looks of the Clairmont, while the handlebars of the Point Beach seem to allow a more upright seating position. Probably gonna want to go with function over form. Besides, the paint will probably flake off anyway so I can just give it a respray if I want black instead of blue.:rolleyes7: Both have smooth road tires, ready for a friction kit.

    Now for the friction kit. I WAS going to go with a BMP kit, but they seem to be DOA so it is between the Staton and DAX. I am leaning toward the Staton for quality and they can give me a throttle cable ready made for my engine. The only real question is the roller size. I would LIKE to go for the 1 1/4" roller for the top speed, but realize that due to my weight I may need to go with the 1 1/8" roller. The fact that hills are effectively nonexistent where I live will obviously play a factor in this. Using some math I can estimate that the 1 1/4" roller would give me an extra 3-4 mph on the top end vs the 1 1/8", if the engine can manage it, with me helping out on the low end.

    What roller would you guys recommend I get? Anything else you could think of? Am I being an idiot?:dunce:

  2. lowracer

    lowracer Member

    The Tanaka 33 looks about as powerful as my Subaru Robin 35 both rated @ 1.6hp.
    I too bought the $89 deal Tanaka but its still in box with no plans.
    I use a 1.25" roller on the Subaru w/BMP & it goes almost 32mph but I weigh 170.
    Acceleration from a dead stop without pedaling is weak, but if you dont mind pedaling a little to get going, I'd say get the 1.25" roller. If you dont need to hit 30 mph & like better off the line acceleration, get the smaller roller. I dont think the Suby or Tanaka 33 can pull a 1.5" roller.
  3. Happy Valley

    Happy Valley Active Member

    With the what you've stated, rider weight, a heavy bike and that engine on flat terrain, the largest spindle I would use would be 1 inch, max. If there were any amount of grade at all I'd say 7/8".

    I built a MB for my wife, who is petite, on a very light bike with a Staton friction drive and a Mitsubishi 33cc engine. I weigh 200 lbs and riding it on flat terrain with a 1" spindle is about all that small of an engine wants.. A spindle any larger and I would be pedaling a lot more than I care to.
    Last edited: Oct 12, 2011
  4. Crosshair_84

    Crosshair_84 Member

    OK, so looks like I should limit my choice of roller to 1" or 1.125" rollers. I will eventually be adding an expansion chamber to the engine for improved performance.
  5. Happy Valley

    Happy Valley Active Member

    A tuned pipe will help give a bit more grunt on these little guys, particularly on the low to mid range where it's needed. Problem is finding one that's tuned and fits but doesn't cost more than the engine. I've got the TLE 33 and a TLE 43 on another bike, 10ccs doesn't sound like much but it's 30% larger and on engines with a piston the size of a large coin, it does makes a big difference. As they say and to a point (legal wise) it's true, no replacement for displacement.
    Last edited: Oct 13, 2011
  6. darwin

    darwin Well-Known Member

    I have the r/s kit and weigh 220, the 1 1/8th roller seems to be the best overall compromise for speed and torque. I'm guessing 25/27 mph max speed and going up hills if you use the right gear along with the motor theres no hill you can't do.
  7. Crosshair_84

    Crosshair_84 Member

    Well I went with the Schwinn Clairmont and the 1.125" roller. Here is the result thus far. I don't have the throttle and kill switch cable tied down yet.


    The friction kit blocks the rear brake from functioning, I'll have to cut of a small corner on the front to get it to work. Some of the Staton kits already have that cutout made so I know I won't be taking away anything structural, just have to make sure to make it neat. Front brake has proved completely adequate thus far.

    I've read that the engine output of the Tanaka increases by about 27% after the initial break in, so I've been driving it around the block, keeping it at around 50% throttle and below. Tried a couple of short jogs at full throttle after awhile just to check out the engine performance, hope it picks up once it breaks in all the way. Still don't have 1 tankful through the engine. Need to put a light on it so I can ride around at night and get the break in done before the snow comes. Stupid short daylight hours. I'll also look into getting an expansion chamber as well.

    Just for fun: I've also seen a few comments in the past about people asking why nobody makes a diesel moped.:grin5:


    The Tanaka in front, on my bike, weighs less than 7 pounds. The Petter AA1 industrial diesel engine on the milk crate weighs ~130 pounds and puts out about the same amount of power when it's running and turning the generator. (The rusty black thing on the front of the engine is the generator.) Imagine trying to bolt that thing onto a bicycle.:sweatdro2p:

    Though on the flip side, the Tanaka is rated to last 1,000 hours, the Petter is rated to go 2,000 hours between overhauls. So if you run your moped 24/7 for months at a time then the Petter may be the one to look into.:jester:
  8. Happy Valley

    Happy Valley Active Member

    On more than one occasion I've added extensions to the U bracket to clear a brake bridge and thus not needing to cut anything.
  9. Crosshair_84

    Crosshair_84 Member

    The problem with that though is that on the bike in question the U-bracket is pointing more upwards than backwards. I do have an idea as to how I could extend it, but both require modifying the kit and just cutting off that corner of metal is much simpler.
  10. Happy Valley

    Happy Valley Active Member

    Do it how you like but actually there is no problem, just angle the extensions of the required length precisely where you want them. Using the stock U bracket attach the extensions with a length of all-thread right across to prevent any flex and lock it all together tight with 2 opposing nuts on each side. I've done it numerous times with much longer extensions than you'll need and it has worked very well, no mods needed. Keeps everything stock if you ever wanted to sell it. Good luck.
    Last edited: Nov 13, 2011