mph issue

Discussion in 'Motorized Bicycle General Discussion' started by Randog707, Nov 15, 2009.

  1. Randog707

    Randog707 New Member

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    drilled a few holes in the carb cover today,took it out for a ride and i did fill a difference,rides more smooth thanks for the tip it helped alot.KEEP UP THE GOOD WORK!!!
     
  2. fall_down_stand_up

    fall_down_stand_up New Member

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    Im not big on the thin smooth tires....My bike handles alot better with the wider tires....The tread on my tires are were there is always tread on the ground so there is no bumping and I dont get flats anymore....With the smooth tread tires I was getting flats all the time....
    My oppinion is the beachcruiser tires with light tread....No more flats....
    John-John
     
  3. Venice Motor Bikes

    Venice Motor Bikes Custom Builder / Dealer/Los Angeles

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    It's sounds like your engine is 4-stroking... (it's a little too rich)

    You should run about 4 gallons of gas through your engine before you start trying to tune it, because it will keep changing as it breaks in.
    Also, if you're planning on modding your pipe or getting a expansion chamber, you should do that before tuning the carb!
     
  4. Randog707

    Randog707 New Member

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    Venice,I think your right.I leaned it abit,and its running smother.also I order a new ada racing air fillter from Sick Bike parts,do they help any? will the filter help proformance at all?
     
  5. bairdco

    bairdco a guy who makes cool bikes

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    yeah, a good filter will help your motor breathe better, giving you better performance. the stock sponge isn't designed for performance, it's just there to keep the crap out, like a lawnmower's.
     
  6. Randog707

    Randog707 New Member

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    Right on Bairdco,the filter will be here thursday,I'll slap it on give it a run and post back on how it ran.Oh yeah I also order a 36t sprocket it will be here on thursday as well,I'll put the filter and sprocket on and give it a test ride.thanks for the reply Bairdco
     
  7. Venice Motor Bikes

    Venice Motor Bikes Custom Builder / Dealer/Los Angeles

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    Also, don't re-jet your carb until after you put on the new sprocket!!! (That changes the way the engine runs too!!) ;)
     
    #27 Venice Motor Bikes, Nov 17, 2009
    Last edited: Nov 17, 2009
  8. Randog707

    Randog707 New Member

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    Thanks Venice,will do.New carb and sprocket will be here thursday,I'll put them on and post back on how she rides.
     
  9. captainrichhill

    captainrichhill New Member

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    I had the same issues with my bike bogging down at the top end. I figured it was too rich because I would get on a long straight away and run at full throttle. As the fuel in the carb float bowl was consumed it leaned out the mixture and the motor accelerated about 3-4 mph then would die from too lean (out of gas). That's how I knew it was too rich. If you do that procedure and it doesn't accelerate before it dies then it might be too lean.
    My $.02
     
  10. Bikeguy Joe

    Bikeguy Joe Godfather of Motorized Bicycles

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    The surging problems are from fuel starvation. If your engine is too rich and you go WOT and it starts surging, there is not enough fuel flow, AND it's too rich.

    Fix the fuel flow issue before you start "modding" your engine.

    A new air filter, or putting holes in the existing one will only allow more air in, it's not going to "fix" anything, except a slightly rich mixture.
     
  11. Venice Motor Bikes

    Venice Motor Bikes Custom Builder / Dealer/Los Angeles

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    I've found on my bikes that the 'surging' is from the engine being very close to being the right mixture but a little too much on the rich side. it feels like the bike is bogging & then it will get a little 'crisp' burst of speed, then go back to bogging... re-jetting a little smaller has always fixed it.
    This is also how I know when I have the jetting right, it will run real crisp & clean with just a small bit of 4-stroking. (the little bit of 4-stroking tells me that it's not too lean!!)
     
  12. Tim_B_172

    Tim_B_172 New Member

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  13. Bikeguy Joe

    Bikeguy Joe Godfather of Motorized Bicycles

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    Could it be possible that the smaller jet uses less fuel and allows the restricted fuel flow to "keep up", also allowing for the right mixture at the same time? (slightly too rich+restricted flow=surging) (smaller jetting+restricted flow=just right).
     
  14. Tcams

    Tcams New Member

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    I just went for a ride to test after i tried to port match my exhaust and intake and at WOT it seemed like it was "surging" as venice stated above. Im not positively sure but at WOT it would bogg down and right after pick up speed. How do I rejet a little smaller.

    What else could be doing this??

    Thanks
     
    #34 Tcams, Nov 18, 2009
    Last edited: Nov 18, 2009
  15. Tcams

    Tcams New Member

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    After working on my exhaust & intake manifold, waited a few hours and took it for a spin and it took a couple tries to start, with the choke on. When I got it started and gave it a lil rev it bogged down and then died. I started it up and adjusted the idle screw to where it sounded good.

    When riding the motor just doesnt sound right and I dont know what to adjust. I checked the plug and cant tell if its to lean or what. Ive never touched the c-clip since I put the motor on. I looked at it and I cant tell what everyone means by moving it up or down a "Notch". Any suggestions???
     
  16. Bikewithamotor

    Bikewithamotor New Member

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    You might want to try mounting your engine a little tighter
     
  17. Nashville Kat

    Nashville Kat Active Member

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    TCAMS ZONIE:

    I would advise consulting a local bike shop or two- my rims are alloy on a newer Micargi cruiser. The 26 x 2.25 were easily replaced by 26x 1.75. That's a gain of 1/2" in narrowness. But the new tires are smooth tread and weigh much less too. I was able to use the same tubes, ad the tires only ran $10 each- but then I've had a lot of experience changing bike tires through the years. Be carefull not to pinch the tubes if you do this!

    The first thing you'll notice is how much easier the bike pedals even before firing up the motor. The motor notices the difference as well.

    I also eventually put the 27 x 1 1/4" wheel on the front, which is even narrower still. But this usually will require another brake- a road brake with a sufficiently long reach, mounted through the center hole in the fork above the wheel. This brake is a Campagnolo road brake- I don't recommend because it took special boring of the center hole, and reaming of the sides of the brake to get enough reach.. The back one would not fit if I try to put a 27" wheel on the back, and I'd need a brake with a longer reach, because the center hole of the cruiser frame is drilled at an upwards angle for a fender, not a caliper brake- But the front brake really works much better than the original cantilever.

    Recent photos and one from last summer, just after the first tire change-
     

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    #37 Nashville Kat, Nov 18, 2009
    Last edited: Nov 18, 2009
  18. Venice Motor Bikes

    Venice Motor Bikes Custom Builder / Dealer/Los Angeles

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    Sure, it's possible, but I really don't think it's a restricted fuel flow issue, because these carbs don't need that much gas flow; & if the flow was restricted at WOT, wouldn't it just keep getting leaner & leaner until the engine just shut down or burned up?
     
    #38 Venice Motor Bikes, Nov 18, 2009
    Last edited: Nov 18, 2009
  19. fall_down_stand_up

    fall_down_stand_up New Member

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    Nashville Kat,I just dont agree on the skinny smooth tires becouse with the wider tires I have better handling and control,also a tire with semi tread(tread always on the road with no bumming)keeps me from getting flats....When I had smooth tires I was getting flats every week,sence I switched to a beachcruiser tire with semi tread I havent had a flat in 6 months....
    John-John.shft.
     
  20. bairdco

    bairdco a guy who makes cool bikes

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    jeez, this threads all over the place...

    venice and joe, my bike used to surge all the time, not bad enough that i cared, and almost always under load. i figured it was because it was too rich. from past experience with mikuni sidedrafts on 4cylinders, the car would "burble" from getting to much gas. it sounded like it was drowning.

    applying that to my bike, after i built my candleholder velocity stack, the bike rarely 4 strokes at all. even up super steep hills. it'll slow down from the load, but it doesn't bog, 4stroke, or burble. just keeps on chugging.

    every now and then it gets that little surge, but it'll power right through it. so what worked for me, was to make it breathe. i didn't lean it on the fuel, i just increased the air. my clip's at the second from the top notch. and it is (top notch, that is;))

    as for you other guys, skinnier tires have less rolling resistance, but not necessarily less traction (look at a road racer going around a corner at 50mph,) they're smoother and faster, on smooth and fast surfaces.

    fatter tires cushion the bumps better, keep you upright at slower speeds, and provide better traction in harsher conditions.

    off road "knobby" tread leads to a bumpier ride, giving more vibrations you'll most likely feel in the handlebars, and will ultimately be slower than a smoother tread, but work great if you go off road, or in sand and gravel.

    for cruisers, a fat street tread is probably the best way to go. plus, it just looks right.

    the best tire for wet leaves, oil, slimy gutters, and ice, are ones clean enough to not mess up your carpet when you're home watching tv during these conditions.
     

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