Tuned pipe...One step closer to production!

Discussion in 'Dealer Advertisements' started by andyinchville1, Mar 2, 2008.

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  1. Hi all,

    As some of you may know, I have been tinkering with making a tuned pipe / expansion for our little engines...Well I am happy to say I am 1 step closer to an actual production model....I will try to post some pics here now (this model is specific to the Dax 70 but may fit others as well).

    The unit was designed the most difficult installation (small frame mountain bike, low rake fork, and oversized tubes) so it should fit on other bikes easily. The unit is adjustable as well without need for difficult bending. Weight is approximately 5.4 lbs. in prototype form. This pipe was designed to be far away from the riders legs so as not to interfere with normal pedaling and bicycle use.

    Pipe will allow you to gear up substantially....It will pull me up the steepest of hills here in Charlottesville using a 36T rear sprocket faster than a stock bike with a 44T sprocket....I am thinking of gearing up even more in the future.


  2. Hmmm....pics did not take...I'll try resizing since I think that is the problem.
  3. OK another try...I think it's Gonna work! ;-)

    Attached Files:

  4. Skyliner70cc

    Skyliner70cc Active Member

    SIGN ME UP FOR ONE! It'd be great to be able to use a 44tooth sprocket in Colorado! I'm currently using a 50tooth and there are some hills that the engine struggles on.
  5. Xtrm84

    Xtrm84 New Member

    Holy cow! That is one sweet pipe!!!! Ill take 800!
  6. Figure on a price yet? I need to know this. I hear people talk about a 2 stroke powerband. Is the Happy Time powerband with an expansion pipe the same type of powerband you feel in a 2 stroke dirt bike? I mean does it go mmmmmmAAAAAHHHHH!!!
    Personally and this is just me,I like riding the bike trails and the very look of this pipe may just be the thing that would kick me out. But then again...I can always switch to the stock pipe when I know I'm gonna be on it.
  7. JemmaUK

    JemmaUK Guest

    If you can fit that up for the GEBE 32/40 count me in :)

    I have found a tuned pipe for them but the company wont deliver to the UK *sigh*

    Jemma xx
  8. fastboy9

    fastboy9 Member

    that looks fantastic! i'm definetely interested!
  9. Can you adjust the carb on these Happy time engines?
    I ask because if you can't, a good tuned pipe can run the motor lean,
    causing all sorts of problems.

    I have no experience with the HT, but a lot of experience with goped motors,
    and tuned pipes. I need to run more rich with a pipe as a rule
    or there is a chance of seizing the motor.
  10. azbill

    azbill Active Member

    the only adjustment is moving the needle up or down
    ...and an idle screw
  11. Skyliner70cc

    Skyliner70cc Active Member

    If you are concerned about running lean, you can drill out the needle valve or replace it with a larger one.
  12. HI All,

    Thanks for the kind words on the pipe....It's taking me quite a bit of time to get to this point for something as seemingly as simple as a tuned pipe so I really have to give my admiration to Dax for getting a whole engine kit together...WOW....That had to be a lot of work so thanks for your patience on this seemingly easy pipe!

    As far as final pricing I have not gotten all that figured out yet....still looking for a place that can hopefully offer some degree of mass production....I don't really have a feel for how well this will sell (I wish I could count on the 800 units mentioned above HA ;-)....)
    so ultimately they may have to be done as one offs....I guess like the sprockets...although the sprockets are quite a bit more automated....this would probably involve quite a bit more hand work though.

    The other option I have toyed with is making them available as kits with only minor final fit welding required (the expansion chamber and critical pipe lengths would all be pre- made of course...any muffler shop could do it since the metal is fairly heavy gauge)...the important parts (header length, chamber etc...) already have been optimized (of course I use optimized a little more loosely because the pipe design had to consider that this pipe may be used on any number of different frame sizes and configurations with most likely a few different engines)...what is important though is that the pipe works very well for the Dax 70 (I built it for that since that is what I am running on my bikes).

    As far as the Gebe engine fit....I do not thing that this pipe would optimize performance for that engine (it may help some if the stock exhaust is severely restricted BUT as far as packing the cylinder with extra air / fuel as a properly tuned system would a separate pipe would probable have to be made for that purpose) since a lot of different factors apply to making the pipe (engine size / displacement, port timing etc...). This pipe will help the Dax 70 and something very similar in terms of engine displacement and port timing , RPM range etc....

    As far as sound, I will try to make a You Tube video soon....I think it sounds lower pitched, about the same sound level.....As far as coming on the pipe....it does have that sound Large mentioned.....Not as extreme as a peaky dirt bike engine since the pipe was
    tuned for smooth mid range but there is a definite step where it comes alive...

    I'll try to work on the video soon when my girlfriend is off later this week if the weather is nice.

    Thanks for looking!

  13. Man that is so tempting.
    So tempting.
    I hope you can make it affordable.
    That frame you got that pipe on is almost identical dimension wise to my bike.
  14. fastboy9

    fastboy9 Member

  15. I like seeing the person by video. Nice job,Andy!
    Maybe in the future,but right now I need Moop on the bike trails!
  16. SirJakesus

    SirJakesus Guest

    Awesome video Andy! I really enjoyed watching it. Looks like that tuned bike hauls extremely well up that hill even when it's cold with that tiny sprocket. I'm very impressed. Nice work!
  17. Demosthenese

    Demosthenese Guest

    nice video man. As soon as there available i'm in, seriously, really excited. Any estimate on costs? Personally it's the kind of upgrade i'd probably be wiling to buy for up to $150 including shipping. I wouldn't spend more on it then i did on the engine kit itself, i don't think. But if they're being done as one offs, perhaps that is too low?

    keep us posted!
  18. fetor56

    fetor56 Guest

    Impressive Andrew...please post the price when your ready.
  19. KanesKustoms

    KanesKustoms Member

    I like it.... Nice Job very good craftsmanship and it seems to perform very well

    But Dude,,, your going to get pulled over... even so I hope you sell a million of them