my top speed...not so

Discussion in 'Frame Mounted Engines' started by wayde, Aug 11, 2007.

  1. wayde

    wayde Guest

    He everyone, I've seen lot of you saying that your hitting top speeds around 30-35mph but i can't seem to to get my kings f80 to do more than 20 mph i think it's tuned to the best of my knowledge any suggestions would be helpful
    Last edited by a moderator: Aug 11, 2007

  2. gone_fishin

    gone_fishin Guest

    that is so not enuff info, have to take us thru where you're at now, current settings and such, before anyone would have a clue.
  3. Edward

    Edward Guest

    First how are your plug chops? Nice chocolate or white grey or black? Plug gap correct? and plug of an aftermarket origin? Have you replaced the intake gasket? the red ones dissolve and you go lean and then dead. Is the engine broken in? What fuel mix ratio? What is the aprox. weight of the bike and rider? These are all factors and there are more, which can have an effect on the top speed. Give us the sit.rep. and we can go from there.
  4. wayde

    wayde Guest

    well i got the motor a week ago rode it every day, instruction say 20/1 mixture so that's what it is, bike is 36 lbs rider is 230 in take gasket is good plug is good had trouble tuning carb but it runs best on the highest notsh of the needle i tried the others and it got progressively worse while riding the throttle hits a spot and the engine sounds awesome and there is a lot of power but only for a second
  5. gone_fishin

    gone_fishin Guest

    thanks 8)

    if you're still in a healthy break-in, i'll guess the surges are the rings getting close to a nice seat...varying your speed every coupla miles or so will help.

    when it starts to gain more power thru the range, i'd suggest trying the second mixture slot down again before changing the pre-mix ratio. it sounds like you may be in a really lean condition right now.

    if the performance is consistently low, you gotta go after a leak. if the intake and carby are good to go, closing the choke should kill a warm engine.

    that's not all, but it's some...try kicking back & reading thread after thread for a while, there's a surprise around every corner here :)
  6. wayde

    wayde Guest

    well i guess i'll run it for a while and see
  7. wayde

    wayde Guest

    well everyone i think i was trying to rush things a little the more i run it the better it runs and faster it goes. i have also taken the time to count and i have a 44 tooth sprocket
  8. gone_fishin

    gone_fishin Guest

    good news!

    the happy-time is great therapy if ya let it be 8)
  9. If it's speed you need....break in your engine well and get a smaller rear sprocket then HOLD ON!!!
  10. wayde

    wayde Guest

    how small of a sprocket is good i have a 44 tooth and i don't really know which company is the best yet, i have a power king 80 my next one will be from dax
  11. 44 T and 48 T seem to be factory standards....Speed demons go with 32 T or 36T....Really rider / bike weight, altitude, and terrain has a lot to do with gearing...I live in a hilly area so I went 40T but I do have bikes with 36 T , 40T and 44T.....The 44 T is the fastest accelerating / best hill climber....It will hold off the other 2 bikes until about 23 or 24 MPH, then the 36 T bike pulls ahead and keeps on pulling away....On the flip side, the 36 T bike requires more pedaling from a dead stop until you can let the engine take over propelling the bike (unless you excessively slip the clutch which is not good for clutch life)....The compromise I used was a 40 T....I have thought about trying a 38 T tho....
  12. drimpact

    drimpact Member

    I just switched to a 36 tooth and was a little disappointed in the speed difference. was using a Dax kit 48 tooth, and could cruise at a comfortable 25-28 mph. Now I cruise at 28-32 mph. I was expecting a little more speed, but it seems I gained just a little, but my motor is much happier at a little less RPMs. anything under 20mph and the motor really lugs out.

    I am waiting for a new wheel to arrive and I will bolt on the 48 tooth to it for a quick change for off road use. 20 is to fast on a lot of the trails I ride and the 48 will pull hills much better.

    By the way I weigh about 265 and I know if I can get back down to the 200 pound range the bike will be faster still.

    Good luck with the break in, it is truly the most important time in the life of your motor.
  13. gone_fishin

    gone_fishin Guest

    the sample i have coming from andrew is a 40-tooth. i have a stock 44 now, & get great take-off, good hill-climbing, & a decent top-end of 34mph.

    i didn't want to mess with a good thing (too much) but i did want less rpm at cruising speed, hence my choice...i'll post the final outcome when i test-drive the soon to arrive sprocket, as well as my honest comments on the quality of the worksmanship.
  14. Call me different,but if i was to change my 44 tooth it would be a change up instead of down. To me anything over 25 mph on a bicycle is showing your neighbors you gots a screw loose. I like to relax and ease on down the road gently and smell the roses. Cause frankly,if it's speed I want then I would save up for a Fat Boy.
    Maybe if I had a 50 tooth I can pedal real slowly and ease off the clutch and gently glide away. That would most definetly turn the heads of the "How cool is that" crowd.
  15. Esteban

    Esteban Active Member

    I am with the " Big " guy above. I just cannot see riding a bike at such high speeds. Then again, I have already had my neck bolted back together one time, too !!
  16. nweiner

    nweiner Guest

    My kit came from Kings with a 50 tooth and it was terrible. The engine ran at way too high rpm's and it was no fun. I just got a 44 tooth'er and it is way better. it climbs hills and cruises faster than the 50 would run all out.
  17. wayde

    wayde Guest

    well i put the motor on the new bike and I don't know what's really different but I went from about 30 kmh on the old with a 44 tooth to 49 kmh on the new bike with 44 tooth so i am prteey excited to see what happens with the 36 tooth
  18. Joshboy

    Joshboy Guest

    32 tooth sprok will get you going 35-40mph
  19. gauge

    gauge Guest

    HEY LARGE PHIILIPENO i think i got alot of SCREWS LOSE lol
  20. "Yep. There's that crazy guy again in that motorized bicycle."
    "Look at how fast he's riding. He must have some screws loose."