Reed valve on the cheap

GoldenMotor.com

scott83

New Member
Oct 23, 2009
34
0
0
Indiana
Got my PB reed assembly in today looks like theyll work.... aluminum bar stock on the way ...think its gonna be sweet
 

noco

New Member
Sep 9, 2009
343
0
0
fort collins colorado
Here is a good link I found several years ago on etching youre own reeds for use in pulsejet engines....the process is really simple...it aint rocket science ...but close..LOL.

www.aardvark.co.nz/pjet/makevalves1.pdf

And the page its from with good info on the design/theory of the assembly.

Factors Affecting Pulsejet Valve Life
it rocket surgury!!!

but anyway...how were the results...did this blow the crank seals out???sounds like a great idea if those crank seals can handle it and the motor can handle the higher compression...
 

scott83

New Member
Oct 23, 2009
34
0
0
Indiana
I didnt do the etching process for this ....I spent like 10$ on a pocket bike reed assembly. Haven't had a chance to do any R&D yet .... still waiting on aluminum barstock... to make a decent "cheap" reed block adapter.
 

Attachments

Last edited:

scott83

New Member
Oct 23, 2009
34
0
0
Indiana
Didnt think about blowing crank seals...must be why Hodaka had you do this mod when installing reeds on thier bike www.strictlyhodaka.com/images/reed0006.jpg looks like it would prevent over pressure in the crankcase since intake and transfer would be equalizing until the piston moved past both of them. www.strictlyhodaka.com/images/reed0004.jpg Thanks for the insight think ill be doing this cylinder mod before I install my reed assembly. :)
 

noco

New Member
Sep 9, 2009
343
0
0
fort collins colorado
Didnt think about blowing crank seals...must be why Hodaka had you do this mod when installing reeds on thier bike www.strictlyhodaka.com/images/reed0006.jpg looks like it would prevent over pressure in the crankcase since intake and transfer would be equalizing until the piston moved past both of them. www.strictlyhodaka.com/images/reed0004.jpg Thanks for the insight think ill be doing this cylinder mod before I install my reed assembly. :)
that would definately reduse some of the crankcase overpressuring that i was concerned with...good research...but is this nessassary???how has other peoples been holding up???

oh by the way nice reed valves...how big are they????
 

scott83

New Member
Oct 23, 2009
34
0
0
Indiana
Dont know...thats what I was wondering Ive not heard anyones stories on here I did see a thread somewhere on here that showed Pipelyne (I think thats how its spelled) had made some reed cages assemblies....but nothing on how well they work and they were like $100....... too rich for my blood....Im thinking $20 to $30 here and there is reasonable.....if its a hundred here and a hundred there I'll buy a Different Motor.
It would be good to know if the the cylinder mod is even required. Ill probably try without doing it and see... and if the seals go replace them when I do the cylinder mod.
 

silverbear

The Boy Who Never Grew Up
Jul 9, 2009
8,325
670
113
northeastern Minnesota
Thanks to all for this informative thread. I finally understand what a reed valve is and will be following along as an old, but eager student. Things I can do myself for little money to improve these 2 strokes performance is great. Some of us can't really afford shift kits, expansion chambers, etc. much as we'd like to have them. What I like about this is that with the reed valve in hand the rest of the fabrication is easily within reach of just about anybody with a few hand tools and maybe a dremel to make life easier and of course some patience. I would think that the idea of a used plastic bread cutting board as the mounting material would work well and much faster than aluminum stock. The echo chainsaw reed valve sounds especially good since it matches the stock bolt pattern... what about the pocket bike reed valve? Has anyone tried it yet? Pictures, folks, are much appreciated. Thanks for sharing!
SB
 

PR3C150N

New Member
Aug 27, 2010
69
0
0
NSW
what this is doing, i just what a boost bottle does. after i put mine on, it made the ride smoother, smoother idle, and a bit of extra low torque
 

PR3C150N

New Member
Aug 27, 2010
69
0
0
NSW
hah Sorry :S don’t evan know what a reed valve is. but i saw it stop fuel from going back into the carby , i thought ohh i boost bootle does that lol :S
 

klb6154

New Member
Jun 20, 2010
76
0
0
pittsburgh pa
now that is definatly some killer back yard engineering i love it you could further dial it in by tracing the reed and cutting it from differant types of plastic the more flexible the plastic the faster the reed will open changing the powerband i would add 6 inches or so to youre header as well keep us posted
 
Last edited:

OregonTrails

New Member
Oct 22, 2010
5
0
0
Eugene,or
Do you have an expansion chamber? I believe a reed valve allows for better compression. So if you had an expansion chamber you wouldn't need to tune anything more. The expansion chamber will supercharge it and utilize the ability to compress more.
 

oldtimer54

Member
May 15, 2010
540
6
18
On a bike
Yes, that sounds good. Please continue to share your knowledge. Performance gained through ingenuity as opposed to store bought is always a plus in my book.
Well sharkcruiser I havent seen you around for quite a while how did the reed valve work out for you? Has anyone else working on these have any luck? I wonder why no one has been making and marketing these for HT motors? Any one have any updates? If I ever get my motor started again (been 4 months lol and still no go) this sounds like a great upgrade.