Simple Reed Valve



6blueoval9

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A Reed valve allows your mixture to stay inside the case giving you a consistent air to fuel ratio mixture.

The smaller ones such as the one you are showing will increase low-end power more than anything but can improve midrange a bit as well...your top end however may drop slightly.

You really need a windowed piston to take full advantage of the Reed and you will likely find you need to jet the carburetor richer as well.
 

Tyler6357

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Thank you for responding. I know I have to get the ported or "windowed" piston or cut one myself and I figured I would need to re-jet. I have been looking at different types and have noticed that the reed valves come with 2 (like the one I was asking about) as well as 4 and 6 valves. I figured that the ones with 4 and 6 would work better than 2 but perhaps I am mistaken? I'm using a Dellorto Clone (RT) Carb and I have several jets from size 60-70 and I can make ones if they need to be smaller than 60. My question is: Will this work as well as other ones? Will the ones with only 2 valves work as well as the ones with 4 and 6? Is it really worth it to put on one like this one or should I just go for the bigger ones that are harder to put on? I mean, will I even notice a difference with this small 2 valve type? Also, will I need to change the timing??
 
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Street Ryderz

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Thank you for responding. I know I have to get the ported or "windowed" piston or cut one myself and I figured I would need to re-jet. I have been looking at different types and have noticed that the reed valves come with 2 (like the one I was asking about) as well as 4 and 6 valves. I figured that the ones with 4 and 6 would work better than 2 but perhaps I am mistaken? I'm using a Dellorto Clone (RT) Carb and I have several jets from size 60-70 and I can make ones if they need to be smaller than 60. My question is: Will this work as well as other ones? Will the ones with only 2 valves work as well as the ones with 4 and 6? Is it really worth it to put on one like this one or should I just go for the bigger ones that are harder to put on? Also, will I need to change the timing??
The one your looking at is best suited to stock and mildly done engines yeilding better throttle responce and a slightly better A/F charge volume.The larger 4 and 6 peddal reeds require larger port volumes to make use of the extra A/F charge being pulled into the engine,Along with a much bigger carb to properly meter and deliver that extra volume,You will need a good pipe that allows that extra volume to escape without restriction and the pipes return wave has to be timmed to get the best results from the combination.The timming should also be retarded etheir physically or electronicaly to help keep the engine from beating it's self to death at higher rpm and reduce some of the vibration.
 

6blueoval9

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Thank you for responding. I know I have to get the ported or "windowed" piston or cut one myself and I figured I would need to re-jet. I have been looking at different types and have noticed that the reed valves come with 2 (like the one I was asking about) as well as 4 and 6 valves. I figured that the ones with 4 and 6 would work better than 2 but perhaps I am mistaken? I'm using a Dellorto Clone (RT) Carb and I have several jets from size 60-70 and I can make ones if they need to be smaller than 60. My question is: Will this work as well as other ones? Will the ones with only 2 valves work as well as the ones with 4 and 6? Is it really worth it to put on one like this one or should I just go for the bigger ones that are harder to put on? I mean, will I even notice a difference with this small 2 valve type? Also, will I need to change the timing??
The bigger reeds are as Ryder explained above.

As far as jets I'm not sure a 70 would be rich enough but that's the jet I would try first since it's your largest...Always start rich and work down.

As far as your timing, stock is just fine for that set up.

As far as feeling a difference I'm fairly sure you will on the bottom end and some midrange...like I say don't expect any top end gains with the smaller Reed..if anything you might lose a couple mph to gain elsewhere.

For driving around a neighborhood or somewhat busy street you want the lower end throttle response more than you do a top end speed..It will make cruising around stop sign to stop sign more fun in my opinion.
 

6blueoval9

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I'm no salesman nor affiliated with this company but considering the Reed kit you showed us I would recommend maybe a little better designed model you can purchase here in the USA from ZedaMotorsports.com

You want the RSE Reed valve kit which will come with carbon fiber Reed flaps. Carbon flaps help eliminate a flutter that can occur at higher rpms...they just work better in general and the price is great.
 

Street Ryderz

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I'm no salesman nor affiliated with this company but considering the Reed kit you showed us I would recommend maybe a little better designed model you can purchase here in the USA from ZedaMotorsports.com

You want the RSE Reed valve kit which will come with carbon fiber Reed flaps. Carbon flaps help eliminate a flutter that can occur at higher rpms...they just work better in general and the price is great.
The RSE or Zeda reed from ZedaMotorsports ONLY comes as a 40mm stud spacing the ones from MZ like the poster reffered to have both the 32mm and 40mm spacing and the price is the same only difference being the peddal materail and the fiber glass ones that MZ use open better and dont require the ends being properly squared and epoxied to stop the carbon fraying and getting sucked into the engine.
 

6blueoval9

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Ahhh ok...I didn't realize they were 40mm only from zeda.
I usually use a little crazy glue on the carbon to eliminate fraying..I've done that to many of RC carbon chassis parts..works well.
 

Tyler6357

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The one your looking at is best suited to stock and mildly done engines yeilding better throttle responce and a slightly better A/F charge volume.The larger 4 and 6 peddal reeds require larger port volumes to make use of the extra A/F charge being pulled into the engine,Along with a much bigger carb to properly meter and deliver that extra volume,You will need a good pipe that allows that extra volume to escape without restriction and the pipes return wave has to be timmed to get the best results from the combination.The timming should also be retarded etheir physically or electronicaly to help keep the engine from beating it's self to death at higher rpm and reduce some of the vibration.
Thanks for all this great info!! I'm still learning about these things. I should say that my engine is a pk-80 (with the shorter connecting rod), 40mm stroke, and my friend ported it for me on a mill. I'm using a 6cc Fredhead clone. Also, I'm using a good expansion pipe and I scored a FMF powercore 2 silencer for it too. Which carb would you recommend for one of the 4's or 6's?? This smaller 2 that I asked about looked very easy but I was wondering if I would even notice a difference with it. Here is a pic of the bike I want to upgrade with a reed valve.
PIC_2782.JPG PIC_2752.JPG
 

6blueoval9

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I would go with the OZ Reed 4 petal kit for street use and if it's just raw power you want the Dio Reed valve 6 petal kit.

Both will require a little more intake porting to match the opening however.

The ultimate is a case Reed set up but that will require essentially a new motor and they aren't cheap.

The pk80 has a 32 or a 40mm bolt spacing?

To make the most out of either kit maybe a little port timing changes would help all the way around the power band.

It's a new ball game really with the larger Reed kit.

As far as a carburetor with the OZ kit I would recommend the authentic Mikuni VM18 carburetor..They are expensive however at around $80 for one.

If you went the 6 petal dio Reed valve route an OKO 21mm carburetor which are actually well made clones of a Keihin PWK carburetor and are less than $40.00

Again, zedamotorsports has all this on his website and prices are great in my opinion but shop around for options and decide for yourself.

Actually you can get a complete Dio Reed set up with a new fully ported and timed cylinder and windowed piston to match rather cheap and with the carburetor and air filter to go with it all.

I hope your bottom end holds up...lol
 
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