Is this normal? Tanaka 32cc vs Tanaka 40cc, question

Discussion in '2-Stroke Engines' started by Crosshair_84, Nov 10, 2012.

  1. Crosshair_84

    Crosshair_84 Member

    My bike had been put together with a rear wheel 7/8" Staton friction drive with a Tanaka 32cc Engine. I can get about 21-22 mph out of it. I upgraded to a used 40cc and I put in the 1 1/8" that I have for a project I have not gotten to. However, the speed decreased to about 18-19 mph. I then swapped back to the 7/8" roller and I can get up to about 20-21 mph. However, my acceleration has picked up substantially. I don't really need to pedal once I get going.

    I am a big guy and weigh about 270 pounds, but it's very flat where I live.

    I checked the power curves and think that I have found the problem. The 32cc doesn't have good torque figures vs the 40cc, but it puts out max power right where I need it to get top speed, around 8500 RPM, while the 40cc puts out max power about 2,000 rpms sooner, 6500 rpm.

    http://www.tanakapowerequipment.com/pdf/PF_3300_Info.pdf

    http://www.tanakapowerequipment.com/pdf/PF_4000_Info.pdf

    At first I was disappointed with not getting any higher speed, but after riding it a bit, the extra acceleration certainly does come in handy, especially in areas with lots of stop signs where I need to get going back up to speed.

    So it looks like I still don't have enough power to swing the 1 1/8" roller and I've traded about one mph of top speed in exchange for better acceleration.

    Is this about the performance I should be seeing or is there perhaps something wrong with my setup or the engine? The 40cc was broken in when I bought it.

    /Thanks everyone.
     

  2. lowracer

    lowracer Member

    I have both engines Tanaka 32cc & 40cc & currently both are on Dax friction drive units.
    I use a 1.5" roller on the 40cc & it can pull 40 mph. The 40cc is much more powerful everywhere in the rpm range.
    The 32cc can hit about ~30 mph which is just a tad underpowered for my use.
    Make sure to not push the roller into the tire too deep & make sure the tires are inflated to intended pressure. I go faster with harder tires (higher pressure).
    I'd like to get another 40cc or even a 47cc if I can find one?
    -Lowracer-
     
  3. Crosshair_84

    Crosshair_84 Member

    How much do you weigh though? I have the tires at about 45-50 psi right now. Through trial and error I've learned how hard to have the roller on the wheel.
     
  4. Racie35

    Racie35 Member

    I have a tanaka "R" 47 cc on a trike here that works well....alot more power than the stock engine that came on the gocarts we took em off....sxr go carts
     
  5. lowracer

    lowracer Member

    Crosshair,
    I weigh 172 & the bikes weigh about 65 lbs (both Downhill MTB's)
    Racie,
    I'd like to get a 47cc Tanaka....where do you suggest I look?
    Thanks
    -Lowracer-
     
  6. Racie35

    Racie35 Member

    not sure really..its been a few years since I gathered up these 2.....one thing they do well is start first pop well usuallyand the walbro on them is better than the smaller sxr motors..so they have good compression and pop right over and run well.
    I bought these online used and they weren't super cheap but not too bad...I'd sell one for $150 and both for $250 and do the change I wanna to electric on the trike.
     
  7. BchCruizer

    BchCruizer Banned

    Dont those engines only run at 5,500 rpm max
     
  8. Racie35

    Racie35 Member

    I dont know their rpm figures... but they work well
     
  9. Racie35

    Racie35 Member

    IMAG0119.jpg

    here's the trike....an American Tri-Ped
     
  10. Crosshair_84

    Crosshair_84 Member

    The spec sheets I linked in my OP list the max RPM at 11,000 for both the 32cc and 40cc.

    Yea, so my engines have to push about 100 lbs more than yours do, I think that is where my problem lies.
     
  11. lowracer

    lowracer Member

    Bchcruizer,
    I've got a tach hooked up to both engines & they both have hit 8640 rpm's on level ground, no wind, under load.
    I think with mods, the 32cc & 40cc could get to 11,000 rpm's but just with a pipe, they cannot.

    Racie, post some pics of the 47cc engine for $150
    Thanks
    -Lowracer-
     
    Last edited: Nov 11, 2012
  12. Racie35

    Racie35 Member

    I'll go out and take a pic of the one on the trike and the one in the shed in a bit...hang on a few
     
  13. BchCruizer

    BchCruizer Banned

    I looked at my engine its the 4000 it says only 5,500 rpms max..i was wondering why that chart said 11,000 and the engine only says it goes to 5,500 rpms..
     
  14. Racie35

    Racie35 Member

    IMAG0570.jpg here's the Tanaka on the trike.....and I have one more uninstalled
     
  15. darwin

    darwin Well-Known Member

    OP those tanakas broken in yet? At least 2 or 300 miles on them? Thats when you can tell the difference between the 2.
     
  16. rawly old

    rawly old Member

    Can't speak for all, but my Pf4000 has got 185 mi. on it,
    and I'm still gaining speed & power every time I ride. I
    haven't ridden it as much as i might since I'm still fond
    of my gx35/ 7/8" roller setup. When I feel the need for
    adrenalin I ride the tanaka bike. Most of the time
    I'm happy to just quietly putt along a 13/14 mph with
    the honda bike. At that speed it is so quiet people
    don't hear me until I'm 40 feet away.

    P.S. They may be rated to 11,000 rpm, but mine gets
    pretty hot at 8500. I don't think it's a good idea to
    run 'em at more than that. Why screw up a good.
    reliable, and costly engine.
     
    Last edited: Jul 29, 2013
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