Reed Valve Fun?

Discussion in 'Performance Mods' started by geebt48cc, Oct 3, 2012.

  1. geebt48cc

    geebt48cc Member

    Uno, here's a picture of the 7" extension on speed carb that really does help with torque quite a bit. I wonder, once I put Reed Valve on engine, if it would even produce more torque with that same 7" extension attached to Reed Valve/and then the carb?????????

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  2. wheelbender6

    wheelbender6 Well-Known Member

    Get a reed valve from a chain saw engine and give it a try.
  3. Ivan H

    Ivan H New Member

    Hi, if u just wack reeds on without porting the piston etc, u may or may not notice a small torque increase. U'll probly have 2 downjet a tad as it'll stop reversion blowback. If u do the piston port & boost port mods etc, u'll notice a substantial torque increase, tho u'll also need 2 do a sizeable upjet due 2 the much lower intake velocity that results from 180 degree intake. It is worth doing, IMO, so long as ur motor's up 2 it, especially the small end bearing. Cheers
  4. jaguar

    jaguar Well-Known Member

    The reverberation effect of the extended intake depends on its "open end" at the carb intake side. Putting a reed valve anywhere between the engine and the carb kills that effect. Long or short intake tract with a reed valve will not have the same low rpm power boost because there will be no reverberation. The only effect of distance is the distance between the engine and the valve which affects the crankcase compression ratio. It's already too low so the less distance, the better. I think a reed valve without a torque pipe you would get less low rpm power than with piston port intake and an extension before the carb.
  5. geebt48cc

    geebt48cc Member

    Ok, So, Jag, are you saying that the extention I have on there now would still be better than a reed valve? Uno, it not doing anything else to engine?
  6. jaguar

    jaguar Well-Known Member

    with a torque pipe and reed valve you would have very good low end power. with the valve and your pocketbike pipe it would be much less, very likely even less than what you have now with the intake extension. but you could try it and see how you like it. get the Rock Solid reed valve. don't forget to hole the piston and make a boost port.

  7. geebt48cc

    geebt48cc Member

    Ok Jag, I understand, but isn't the expansion chamber from SBP's pretty much the same as a torque pipe?
  8. jaguar

    jaguar Well-Known Member

    don't kill me with laughter, please. ALL, and I do mean all, pipes sold for these engines are made for pocketbike racers for a peaky high rpm powerband. The Torque Pipe is the absolute opposite of that. It is designed for a broad non-peaky powerband. On my bike I have significant power boost from 15 to 35mph. A regular pipe would give you a boost from 30 to 35mph (if that's the top speed). All you people wanting pipes should write the distributors and tell them you are waiting for them to sell you a torque pipe. The plans to make them are free on this forum in the Wild In The Streets section. Tell them that you are in protest against the crapola that's been made available to you up till now. Wave those dollar bills in front of their face and give them reason to make a positive change.