deciding on the right friction drive motor.

Discussion in 'Friction Drive' started by JourneyManDan, Dec 20, 2011.

  1. JourneyManDan

    JourneyManDan New Member

    Hey guys, been lurking the site for a while. Now time to mingle!

    Ive done a few months worth of research and I realized friction drive is right for the way I would like to drive my motor bike. When deciding on a motor, however I cannot decide what would work for me...I need some help from some friction drive veterans and Im not afraid to ask for it... Im young, but one thing I have learned when pursuing anything is to always ask advice from the people who have lived it before you. (plus it makes less stress on my part for making easy mistakes I could have avoided if I just asked!:snobby:)

    I have long debated 2 or 4 stroke engines like countless others on the forums and have concluded that either one will do as long as the quality is good. Im fine with maintaining a motor, but I dont want to have to fabricate all kinds of new parts just to make it work for me...and I want to be able to count on it working, but i understand what basic maintaining is needed for a engine to work the way it should. Im fine with changing parts out, but i do not want to start over modifying my engine.

    I have wondered what type of clutch system is best on a friction drive in terms of minimizing wear the unit. I get used to the idea of a centrifugal clutch, but have only ridden a normal clutch motor bike..I can ride a regular clutch good too its very fun, I like to pedal on all my starts as well..but still cant decide what would be the best for a friction drive..does it really just matter on the way you use your clutch?

    for speed performance...I want something that has good acceleration and cruise speed is not too important but i do want to be able to cruise at 28-35~mph for extended periods of time...

    noise is a very small factor for me. I dont mind it too much, and im fine with pedaling if I know its going to be to loud for the area I am in.

    One thing i am kinda firm on is weight. I want this thing to be fairly light weight..12pounds and under for dry weight...

    Ive looked at a few engines so far...feel free to tell me if I'm in the wrong direction..GP460. DAXGT50R...Predator 99cc...robin1.6hp...and stuff like this.... <---can some one tell me what is the difference in this and the GT50R is? what is the quality? will I be able to buy this and buy and friction drive kit and be ready to build?

    i want pedaling to be easy...and have been wondering what the best way to pedal only with a friction set i remove then roller and pedal, keep the clutch in and pedal?..i would like to remove the roller, how fast is that? is it just a simple unscrew?

    thanks guys. I have been reading up on this stuff for a while, but i have never asked questions to anyone..

  2. Alaskavan

    Alaskavan New Member

    To be able to cruise in the 28 - 35mph range, you'll need at least 2hp. My Mitsu TLE 43 will run about that speed, and I'm pretty light.The GP460 should give enough power. Most kits use a centrifical clutch and are set up so you can raise the engine/roller for pedal-only operation.
  3. JourneyManDan

    JourneyManDan New Member

    What have you heard/know about GP460 on friction drive? I know Mr. 5-7 has one but I read he converted it to chain and Im wondering if there is a critical reason for him to do it, or him getting bored and wanted to do something new..
  4. Alaskavan

    Alaskavan New Member

    I would imagine that the GP460 ate tires at a high rate, and there is the issue of riding in the rain.
  5. JourneyManDan

    JourneyManDan New Member

    well, the rain thing doesnt really bother me all to much, I still like to pedal so its not a big deal. and yes, i have heard that about the tires...but how much of a difference is it? can i find a solution?
  6. wbuttry

    wbuttry Member

    well i use a dax friction drive and a china 49cc 2 banger i been running the same tire on my friction drive since july and cant really see much difference in the tire wear from before and after...
  7. 5-7HEAVEN

    5-7HEAVEN Active Member

    The GP460 is an excellent engine; I have a few on the shelf, waiting for me to cure its Achilles' heel. It is unable to make power in its low end. Run this engine below its narrow powerband and it's a dog. This engine does not like hills with friction drive, ESPECIALLY if you can't get a running start. However, at high rpm, it's powerful! This engine's clutch engages @ 8,000rpm. This is prolly the reason why it's weak @ low end.

    JMO, if you could install a mechanical clutch, it'd be a WINNER! Then you could increase rpms and power at will, especially when climbing hills.

    It is so powerful that rear tires don't last long with friction drive. In two weeks, I had gouges on every inch of the tire.

    Knowing that the 460 needed to be kept in its powerband, the only alternatives were multi-speed transmissions, as the NuVinci hub, internal hubs or 7-8 speed cassettes. Since cassettes were the cheapest options, I used them with a shift kit and a center-frame engine position.

    Problem solved! Get a running start, use the gears and keep the 460 in its powerband. Rear tires last as long as front tires.

    Second problem was its loud exhaust noise. This was easily solved by installing an ADA S1 expansion pipe. Brackets had to be modified to clear the friction drive housing, and also the engine's center-frame position. The Dominator is the engine-specific expansion pipe. It is LOUD, but makes good power. The quietest pipe is the SBP Happy Time expansion chamber. It fits my bike and the 460 snugly. Altho its exhaust flange is a gross mismatch for the 460 exhaust port, this pipe makes good power. It also quietens the 460 so well that you can hear the noise of the engine's internal moving parts at idle.

    The 460 engine's final problem is its clutch. Firstly, its OEM springs are designed to engage @ 8,000rpm. Not good for a cruising MB. Fortunately, low rpm springs are available which allow clutch engagement @ 3,000rpm. The OEM clutch seems well made, but the engineering design of the clutch springs' locations allow them to unhook, then disintegrate between the clutch drum and the pads. I tried replacing the 460 clutch with the pocket bike clutch. It's cheap, bolts on with minor mods and is silky smooth engagement at 3000rpm. The only problem is that the pb clutch has the same engineering design issues. The clutch springs also fall off their post and disintegrate between the shoes. Methinks it's the clutch chatter at off-idle from a standing start that causes these springs to fall off. If the rider pedals from a standing start and engages the engine while rolling, they MIGHT not have clutch spring issues.

    JMO, if someone could fit a high-performance single-spring clutch from a Tanaka 47R engine onto the 460, this would solve its clutch issues.

    Sadly, I replaced my 460 with a reliable Tanaka 47R racing engine. It has less power, but I've never had a problem with it. This engine DOES lose power climbing a hill, but the multi-speed cassette keeps it in its powerband.

    Methinks a mechanical clutch would also help this engine, but no one has devised such a retro-fit component such as this.
    Last edited: Dec 22, 2011
  8. The Mitsu 43 would do the job for you. I think you might be even happier with a Tanaka 40 or a Honda 50. The Honda is a little heavy. The Tanaka is a very modern, state of the art design, quieter than the Mitsubisi, and while you say noise isn't a problem for you, I'm afraid it will become one eventually. I used to ride loud motorcycles and loved the sound around town or for short hauls, but long distance touring or riding for more than about an hour, the noise becomes very irritating and even causes fatigue.
  9. JourneyManDan

    JourneyManDan New Member

    Thanks for the info Mr. 5-7...helps alot with my decision. Two weeks and signs of that kind of wear doesn't appeal to me...but i do live in Florida which is very im thinking maybe the decrease in incline will save some wear and tear for my bike. what is your recommendation for me to get? based on my first post..
  10. JourneyManDan

    JourneyManDan New Member

    and Mr. Mike, thanks ill look into thos engines. i hear tanaka is very reliable based on what most people say on these forums. and the more i think about it i find my self not wanting a engine too loud but i play drums my hearing sucks anyway lol
    Last edited: Dec 23, 2011
  11. 5-7HEAVEN

    5-7HEAVEN Active Member

    The Mitsubishi TLE43 2.2hp engine is an excellent engine. So are the Hondas and Tanakas. Keep in mind that the Honda 50 needs about $150 more in parts to bolt onto the popular 78mm drive assemblies.

    This is your introduction into motorized bikes. Baby steps in the beginning, please.
  12. JourneyManDan

    JourneyManDan New Member

    yea, I'm not too gung hoo and set on wanting to have a overly flashy engine, because I rather save a headache later..I just want something high quality I dont wanna be stuck complaining that my engine wont work after a few weeks..

    If the GP460 is to much for me to handle as my first bike, I wont argue with that! I plan on doing future builds any way like every one ends up doing.

    My room mate has a chain drivin pre assembled nirve bike (here it is) [​IMG]

    I want my friction drive to be able to keep up with him and not take a beating for it...this is the bike Im using. [​IMG]

    I'm by no means a speed the kinda guy who like Mr2's as a car because they handle well..I like quick and nimble..but like I said I dont want to get left in the dust by his bike. I'd say it goes speed up around 35+
  13. 5-7HEAVEN

    5-7HEAVEN Active Member

    PM to you, JourneyManDan.
  14. Your desired speed is a bit high for friction drive. I'm fairly new to this myself, but have done a lot of research. I do not have anywhere near the speed requirement you want, I'm perfectly happy with 20 mph top speed, which is the legal limit for motorized bicycles in my state. They also have a limit of 48cc for engine size. I already have motorcycles, so if I want to go fast I ride one of those. IMO most bicycles, especially bikes like the Huffy Cranbrook, which I have, are not safe at 30 mph.

    Anyway, I elected to go with a Staton friction drive kit, with the Robin-Subaru EHO35 engine and a 1" roller, and have been very happy with it. I have better tires on the way. It's only fault is noise, I used to own a VeloSolex moped, and it was whisper quiet compared to the R-S, and it was a 2 stroke, but had an elaborate muffler system. Most people around here have an issue with motorized bicycles, so quietness is definitely a virtue.

    For the kind of speeds you are wanting, I would look into a decent brand name mountain bike frame and wheels, and a rack mounted chain drive, with the biggest 2 stroke motor you can get on it. As far as I know, all rack mount drive systems have centrifugal clutches.
  15. 5-7HEAVEN

    5-7HEAVEN Active Member

    Of course, noise is a matter of perspective. In retrospect, my first engine, a Robin Subaru on Staton friction drive was the quietest.

    Upon hearing my Tanaka engine idling in the parking structure, my coworker commented "Your engine is loud." "No, it's not", I replied.

    When compared to a modified moped or motorcycle, my MB's not loud.:whistling:

    When compared to a regular bicycle, my bike is deafening.:ack2:
  16. JourneyManDan

    JourneyManDan New Member

    Im starting to lean toward chain drive again...but I just love the idea of how simple friction drive is, and how I can disengage to roller from the tire to pedal normally with no resistance...I also see that these speeds Im asking for are slightly unrealistic...but i hear so many things from so many different people...
  17. Alaskavan

    Alaskavan New Member

    I don't think the speeds you're looking for are unrealistic (and I have a toy that will do 50). If you go with the 460 and friction,1; You can make up for a weak low-end by using a smaller (1" or 7/8') roller. and 2; I believe (5-7 would know) that the 460 has enough top end rpm to still give good speed.
  18. grinningremlin

    grinningremlin Active Member

    I started with a HF 52cc on a BMP 1.25 drive, could hold 30mph for as long as I could take it maxing about 35mph, but depending on the road, over 25mph is getting to the sketchy range.The 2-stroke tended to be jumpy on the throttle, combined with the power could get scary.I have since moved to a RS EHO35, I have to pedal more in headwinds, but it takes me plenty fast, and the easy starting was worth the extra $$.
  19. Greybeard

    Greybeard Member

    I have a PF33 Tanaka with 1" roller. The engine is very light, and pulls me around respectably. I weigh 200lbs and I'm 6'3". Cruises 25 fine on the level and tops close to 30 with no wind and a little tuck. Doesn't seem to abuse the tires and I help it up the steeper grades. The Tanaka will last a long time.
    FYI. My motor came with a owners manual for Canadians. It recomends 30-1 oil mix and not the 50-1 they advertise to get C.A.R.B. and EPA approval here in the States. That tells me that all this lean mixture hooey, is just that. If you want it to last a long time, don't thin it down too much.
  20. Esteban

    Esteban Active Member

    I live in flat Florida as well, & prefer the simplicity of friction drive. Your weight will have a big impact on top speed. Have you ever ridden a bike at 35mph ? That is fast on a bike , at least in my opinion. I prefer about 20 mph, overall. This speed is safer, draws less attention from the cops [ Florida laws are ??????? ] & is easier on the bike, motor, & my butt. My tires need replacing from dry-rot before being worn out. Learn to properly drive a friction drive . Compare how easy it is to fix a flat on the road with both type drive trains. I had 3 flats in one day , so friction drive is my favorite.