Making third intake on 66cc.......................

[geebt48cc]

Yes, see here (at least in my area of the states) the highest octane that one can buy is 93?! I know with higher compression that you need to use a higher octane, but I've just been using 87 octane. So, in having said that, I need to start using the better higher octane next tank! I've put the jumpers for my Jag CDI somewhere and can't find? I'm using the it now without any jumpers at all. I've found that the engine runs best without any of the jumpers.

So, Fabian, are you saying that you think I should not drill holes in piston, and just maybe bevel the top of piston for intakes? Uno, the main concern I have about the bevels, is the amount of pressure duration they can take over time? See, one would think that you would need to be very careful, because that's where all of the compression load is directed. I'll get reed valve this weekend, and just install as normal and see what happens?! I'm like you in really just wanting the low end torque, not being so interested with the highs. One thing though that I keep on hearing is that the new reed valve isn't a bolt on fix of torque?

With the link you sent, they say that one needs to use the NGK 8...................I've only been using the NGK 6. I just wonder how much a cooler plug would really help with the high compression heat on engine?

 

[Fabian]

On the Jaguar CDI, the maximum ignition curve is attained without any jumpers, or so the instructions on the website lead me to believe, which seems to mirror my experiences.
Jumpers can be pulled off the back of any hard drive you are not using.

There is no right or wrong with drilling out the piston or port matching the piston to the intake port roof, because crankcase vacuum controls the air/fuel mixture inflow and the reed valve is the sealing mechanism when the crankcase transitions from vacuum to positive pressure.
From a theoretical standpoint, the piston would give it's maximum intake duration with the intake piston face completely cut away except for the piston ring area. It's obvious that this is not practical, nor would the piston be mechanically stable with such a large weight differential between the intake and exhaust face.

If carrying a spare reed valve, you can hack away as much of the piston as you feel comfortable with or to the desired specification, because you don't have to worry about the piston being critical to the intake timing cycle, as the reed valve covers this timing phase, however, if you want to rely on the piston as a backup device to the reed valve, you'll need the intake port to be timed by piston travel, and that will govern how much material is removed and how much you are prepared to compromise on the idle quality and rpm transition quality.

One thing is for sure: the reed valve intake is a bolt on device and it's not a fix for torque because the engine already had torque to begin with. It must do something being a beautifully shiny and beautifully machined piece of billet art work that just happens to be bolted onto the engine.

That it reduces intake noise and reversion with consequently less oil and filth dripping off the air filter and (carburettor jetted correctly) increases low and midrange torque is an interesting side effect of such a beautifully shiny and beautifully machined piece of billet art work.

 

[geebt48cc]

Yes, but you've also need to understand that with the extension I have on there now, there's also not ever been any oil and filth dripping off the air filter. I'm sure every situation is different, but never had that as a issue there. I also burn 25/1 ratio chocolate color, to leaning towards rich. (To be safe

I've never really noticed a major intake noise, but when I get reed valve on, I'm sure there will be a change for the better. No, Fabian, there are quite a few mods that one can do once you install reed valve, but I just want to do whatever I can to help the bikes torque at lower speeds.

Once again hoping that it at least will be equivalent to the simple longer intake extention that I have on there now to help with torque? I have hopes even better! Then we can just experiment with these other possibilties.

 

[Fabian]

One of four things will happen: your mods will either work, or they wont work - and - the reed valve intake will either make an improvement or it will make things worse.

* time will tell *

 

[geebt48cc]

Yes, I know............ I guess that I'm just hoping that some magic combination will answer question of more torque out of this tiny creation? ................But, my list is getting smaller with all the mods I do

Glen

 

[Fabian]

That's what 2-strokes are all about: sometimes magic happens

 

[Deleted member 12676]

From my experience the intake extension gives more torque than a reed valve without expansion chamber. With expansion chamber and reed valve you get more torque starting around half the peak rpm. My torque pipe is the expansion chamber I am talking about. You might get the same results with one that's sold for these engines but you'd have to modify it by welding in a baffle extension to reduce the baffle return wave strength.

 

[geebt48cc]

So, Jag, are you saying that really at low RPM's the extention would more likely supply better torque? Well, have hopes that this reed valve will balance out with other advantages than just the extention did. I also will now have a foundation for more internal mods.

 

[Deleted member 12676]

What is strange on my latest test with an intake extension is that it both gave better low rpm power AND revved out higher (by 2mph). But the engine has transfer ramps on the piston which may have something to do with the strangeness. I think before I invented the ramps the extension only boosted the low rpm power. I need to buy another piston and test it without the ramps.

 

[geebt48cc]

With heavy thoughts I decided to order the Arrow reed valve for my Grubee Skyhawk 66cc. Uno, I could very much be wrong, but there does sound like there would be more internal manipulation with mods to get the Rock Solid reed to be at its better?! I am aware that in order to get the FULL FUNCTION out of the Arrow, one will need to open case and stuff for better compression. All and all, I do believe for my personal use, the Arrow is the better situation for my bike. I do realize that it's not as compact, but the bike has the room. HOPE I'M RIGHT???