HP Speed carby

Discussion in 'Motorized Bicycle General Discussion' started by Cylon, Oct 20, 2015.

  1. Cylon

    Cylon Member

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  2. Tony01

    Tony01 Active Member

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    Don't know about the carb, but I would not order from a china seller with a feedback rating of less than 99.3%. Small difference, but you must count the neutral feedbacks as negative as well, and basically double the difference from 100%, so a 99.5% seller has an actual rating of 99% and your guy an actual of 98%. Double the risk.
     
  3. Cylon

    Cylon Member

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    I understand that I just linked to that as an example, I'm more concerned with my original question. Thanks for the warning tho.
     
  4. xseler

    xseler Well-Known Member

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    I didn't do the measurements, but that looks like the exact same carb that I now run. It does much better than the high dollar CNS V3 that originally came on the motor. I also like the fuel shut-off on the carb as extra security while it's sitting in my garage.

    Sorry, but I've never run a plain NT carb.

    Good luck with whatever you decide!
     
  5. crassius

    crassius Well-Known Member

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    if there is sunlight in your area, that red filter will turn pink

    I've had a couple in for repairs and CA gas seems to eat up that extra petcock on the side until no fuel flows - I'd stick with NT style.
     
  6. xseler

    xseler Well-Known Member

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    I've already painted mine lime green, so no worries!

    :D
     
  7. Cylon

    Cylon Member

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    Thank you,
    Looks like I'll keep the stock NT and I'll just get a reed to stop the blow back that I'm noticing.
     
  8. Davezilla

    Davezilla New Member

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    The speed carb is a whopping 1/2mm larger diameter than the standard NT and if you got a bike that can do 40mph, the speed carb can get you 41 - 42mph... Not much of a difference otherwise... On a bike that maxes out at closer to 30mph, it might get you another mph.
    Most speed carbs have a fuel valve on the carb body that can shed off rubber pieces that can get in the carb blocking off the main jet or needle and seat valve but there are some newer versions that don't have this extra fuel valve. I went back to the standard NT carb because of this and never missed that extra mph either, but if you can get the new type without the fuel valve it's a nice carb, but don't expect it to do a lot more than the typical NT.
     
  9. crassius

    crassius Well-Known Member

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    the ones without the petcock seem to have the line straight in from the side where it can be ripped off by a pant leg while pedalling
     
  10. leo

    leo Member

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    i tried the stock carb, the speed carb and the rt carb on mine. all brand new and unaltered. one after the other, on the same course.

    i can say that in my instance, the speed carb outperformed both of them.

    i got the black cover, red didn't match my bike :)
     
  11. maniac57

    maniac57 Old, Fat, and still faster than you

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    RT speed carbs seem to be jetted better stock.
    Still not worth much power over properly jetted NT stocker.
    Sha clone with air screw is very nice upgrade, but NOT all sha's have it so be careful.
    Regular sha no better than anything else.
     
  12. crassius

    crassius Well-Known Member

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    my last 60 or 70 carbs have been the original chinese clone of NT-style - didn't think about it much, but a couple weeks ago I realized that I had not adjusted any of them yet, whereas the NTs usually need at least a needle drop of a notch or two

    jeez, till posting this, I hadn't realized how many kits I'd gone thru this summer either
     
  13. Cylon

    Cylon Member

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    Yeah I have purchased 3 dellorto clone's all with the cone filters and none of them have worked with my engine, all caused 4 stroking even with I went through #60 to 80 jets. My stock NT carb works great with original jet. I have a reed on the way in the mail so I figured I would get the NT speed carb and drop the needle to make it richer for the reed. Not looking forward to pulling the head off again to replace the piston with a holed skirt piston. Last time putting the high comp head back on was a pain. Washers are so tiny.
     

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