Homemade reed valve, the search begins

Discussion in 'General Questions' started by David Bogle, Apr 10, 2016.

  1. skyash

    skyash Active Member

    I got a reed valve in my 49 cc pocket bike motor and it keeps that spray back off the frame. It's Ment to have a balanced bottom end and big bore kit. Ment to make 4 hp and do 12000 rev at the moment it hits 64kmh and revs out so going for a smaller sprocket soon no peddling ever so far after haveing like 10 66cc and 1 for stroke this is the best motor never eny issues and go's like that out the box. just aim and hang on

    Attached Files:

  2. HeadSmess

    HeadSmess Well-Known Member

    i didnt even remove casting flash half the time. just grab engine from box, install, wack on a pipe.

    keep talking HP numbers... i seriously doubt youre getting over 4.

    yeah, my pipes were pretty rough.

    this one was definitely lousy. too sharp on the angles.

    this one was the best.

    and of course, i just dawdled along. maybe i should have pedaled as well? that particular frame though...deathtrap. last time i used it.

    i still havent filled the hole :D
    Last edited: Apr 24, 2016
    lazylightning@mail.r likes this.
  3. Fabian

    Fabian Well-Known Member

    Reed valves are a significant benefit for improving low and midrange torque.
  4. jaguar

    jaguar Well-Known Member

    this page shows a picture of the first reed valve ever for these engines, my home-made one. http://www.dragonfly75.com/motorbike/reedvalve.html
    It was made of aluminum from a cooking pan, held together with JBWeld. The reeds were cut from a sheet of .5mm carbon fiber. It lasted about a year with daily riding.
    I prefer an engine with a reed valve and think the one from Rock Solid is good enough.
  5. Rob H

    Rob H Member

    I agree it should be illegal not to have a reed cage on a 2stroke
  6. lazylightning@mail.r

    lazylightning@mail.r Active Member

    Wow! Thanks for the video! I do agree with you, that you deserve to see a video from me before you should be expected to believe my engine power boasting. And a video you shall get, as soon as I get this engine together. It was nice to see the Australian countryside. My brother married a girl from Sydney and moved off to Australia 10+ years ago and is still there. That bike sure was dawdling along and it was easy to hear how it was challenged by those hills. But despite this, the video made my hair stand on end and adrenaline pour out......watching how you drive down the left side of the road! ;-)
    I found some 3mm diameter spokes with a 262mm length that laced up right nice in a double walled reinforced type inexspensive rim. I use some old inner tubes and slice them lengthwise and use one to wrap around the inflating inner tube from inside and one from outside. This helps protect the inflated inner tube from pinches when hitting pot holes at high speeds. I use some 2.35 tires with knobbies. When I get the wheel built and tightened and aligned up perfectly, I go back and remove each nipple from one spoke at a time and put some rubber cement inside of the nipple and re-install it to good-and-tight. I do all the threads on all of the spokes like this and wait for it to cure for a day or so before riding. This way the spokes never get loose even after riding on rough rocky and potholed roads. It will last a year before they begin to loosen up a bit. Without the glue on the threads, it's a matter of two weeks or so and the spokes get loose. It can seem to happen all at once too. With the glued threads they never become very loose even when they have begun to loosen up somewhat. The nipples are still turnable though, that's what counts ;-)
    I bought some carbon sheet for my reed today. The reed house is ready, I just need to weld up the cover with the tube sticking out....
  7. HeadSmess

    HeadSmess Well-Known Member

    that was the first flat i had in...six or seven years. bloody skinny racer tyres, no good. my preference is for something fat, but that particular frame wouldnt accept anything over 1"... looked good when i first got it, ended up on the roadside collection within 6 months. 99 bikes...never again!
  8. Frankfort MB's

    Frankfort MB's Well-Known Member

    HS how fast were you going in that video? Sounded fast lol
  9. Joshbus

    Joshbus Member

    I have been thinking about trying out a pocket bike engine on my next build , especially if they are more reliable than typical 66cc engines. How long have you had this engine? Any issues since this post ? Thanks
  10. skyash

    skyash Active Member

    Nothing really one pull start since new and Iam never happy with my clutch seems to slip but didn't be for .at the start being a racing engine thay worn about excessive vibration so it shakes it's self to bits locktite everything.and the gear box need a heavy duty chain even a diy tensioner in side and any restrictions to the muffler and it slows it down a lot so it's loud lol and I had to run a 20inc wheel with a 52t sprocket think Iam on a 50t now gets to 7kmh like a dirt bike twice as fast as my best 66cc but I only weigh 65 kg
  11. sp1ke

    sp1ke Member

    using custom modded nuraku reed block with great sucsess as far as i can tell at this stage in my build althou there is a lot to take in to concideration with this mod especially if using external reed blocks the best good to go one is the rock solid and panthers design is good but you are restricted to that inlet size those are the easyest ways my naraku block set me back 35 gbp didnt take a lot to decrease its mass with jb weld whyle keeping a larger inlet without restriction possible similar to arrows design but im using a offset adapter i made because of fouling the frame
  12. skyash

    skyash Active Member

    Have you seen the 3 or 2 stage reeds ?with three or two different Stiffness to the reeds I would like to try one .rev a little and the soft reed moves rev up more and the harder reeds move .made for pocket bikes
  13. sp1ke

    sp1ke Member

    ive had boyesen twin reeds and yes there is an improvement over singles of the same material

    i might try n make some multi petal carbon later on actually not a bad idea