Very effective DIY velocity stack $15

[Jayraye39]

So I built a velocity stack and it works absolutly fantastic. Today when I took the stack off my bike was so rich that I couldnt adjust it properly to run. Since I tuned it with the stack on I never realized how good it actually works. Here is what I did. Bought a $10 torch lighter that stands on its own. It has a trumpet shaped aluminum stand it sits on. I unscrewed the aluminum stand from the lighter and tossed the lighter aside. The stand has a small hole in the in the middle that was for refilling the lighter with butane. I took a drill bit the size of the carb throat (19mm) and reemed that hole out to match my carb. I them broke off most of the face plate or dish of the carb leaving only a tab on either side right where the screw holes are for the filter. After that grab a file and file down parts of the carb that dont allow the stack to sit flat. You want the stack to sit flush as as possible.Then i got some jb weld stick. $5 Its a 2 part putty that you knead with your hands. Took the putty and lined the inside of the alum stand forming a cone shape right down to the 19mm hole. After an hour of drying the putty hardens and then can be sanded smoothly. After smoothing i drilled into the jb weld and through the aluminum. On either side matching the holes with the size and distance of the holes on my carb that was for the filter. Then screw on your stack and your done. Ive bought 2 stacks before doing this mod and niether of thoes stacks performed like this one. You can find one of these lighters at a cigar or smoke shop. The brand is called Ion light and the base is the perfect size. Also they come in many colors so pic the color that best fits your bike. You will have to retune your carb after install i had to change jet sizes but every motor is different you might be able to just move the needle around. You will know when its tuned your acceleration and throttle respons will be way better than it was before

 

[Rochacz21]

Bike looks rad, but not running an air filter will hurt power/efficiency from air buffeting in and out will mess up your carb signal

 

[GW's Motorized]

Jayraye, aren't you trying to squeeze every ounce of power you can outta that engine? I'd suggest you try one of the CDH power reed blocks, from what I've read they are small and efficient.

 

[DAMIEN1307]

Jayraye, aren't you trying to squeeze every ounce of power you can outta that engine? I'd suggest you try one of the CDH power reed blocks, from what I've read they are small and efficient.

I just went to the link for CDH reed valve.

CDHPOWER OZ Reed Valve Kit 19mm

<p> </p> <p><span style="color: #000000;"><span style="font-size: medium;">CDHpower OZ Reed Valve Kit with 19mm intake;</span></span></p> <p><span style="font-size: medium; color: #000000;">Compatible with 66cc/80cc engine cylinder with 40mm stud s

www.cdhpower.com

Take a look what they are saying in that ad.

"CDHpower OZ Reed Valve Kit with 19mm intake;
Compatible with 66cc/80cc engine cylinder with 40mm stud spacing only;
100% Fully Made By CNC machine;
Carbon Fiber;
Compatible with 2 stroke CDH gas engine kit 66cc/80cc only;
Dose not compatible with 4 stroke kit;"

In one "breath" they are saying compatible with 66cc motors with 40mm spacing which is all well and good,
but in the very next breath they are say Compatible with 2 stroke CDH gas engine kit 66cc/80cc only;
This makes zero sense to me, it either works for all or only their own CDH brand.

I really have a hatred of confusing advertising like this which has become all to common with stuff used by us in our little hobby/sport.

 

[GW's Motorized]

I just went to the link for CDH reed valve.

CDHPOWER OZ Reed Valve Kit 19mm

<p> </p> <p><span style="color: #000000;"><span style="font-size: medium;">CDHpower OZ Reed Valve Kit with 19mm intake;</span></span></p> <p><span style="font-size: medium; color: #000000;">Compatible with 66cc/80cc engine cylinder with 40mm stud s

www.cdhpower.com

Take a look what they are saying in that ad.

"CDHpower OZ Reed Valve Kit with 19mm intake;
Compatible with 66cc/80cc engine cylinder with 40mm stud spacing only;
100% Fully Made By CNC machine;
Carbon Fiber;
Compatible with 2 stroke CDH gas engine kit 66cc/80cc only;
Dose not compatible with 4 stroke kit;"

In one "breath" they are saying compatible with 66cc motors with 40mm spacing which is all well and good,
but in the very next breath they are say Compatible with 2 stroke CDH gas engine kit 66cc/80cc only;
This makes zero sense to me, it either works for all or only their own CDH brand.

I really have a hatred of confusing advertising like this which has become all to common with stuff used by us in our little hobby/sport.

I've seen it used on lots of China doll engines that aren't a cdh engine. I've done a bit of research on these and decided on it because it is small and it looks good

 

[DAMIEN1307]

I've done a bit of research on these and decided on it because it is small and it looks good

Doesn't look any smaller or that much different than the ones that come with the Phantoms as you can see on my motor.

 

[DAMIEN1307]

And they are available if need be for replacement as well.

ZTMoto Phantom 85 Bicycle Engine Reed Valve

Looking to replace the reed vavle on your Phantom 85 bicycle engine kit? Now available, the direct replacement valve for your ZTMoto, get yours now!

www.bicycle-engines.com

At least they say its compatable with any of the 40mm stud spacing without contradicting themselves in their ad...lol.

This Phantom reed valve is compatible with engines that have intake manifolds with 40mm stud spacing.

Ps...I do agree with you that the CDH should work on any of these, I just can't stand it that the Chinese instructions and descriptions are total contradictory garbage when they try to translate it into English.

 

[GW's Motorized]

And they are available if need be for replacement as well.

ZTMoto Phantom 85 Bicycle Engine Reed Valve

Looking to replace the reed vavle on your Phantom 85 bicycle engine kit? Now available, the direct replacement valve for your ZTMoto, get yours now!

www.bicycle-engines.com

At least they say its compatable with any of the 40mm stud spacing without contradicting themselves in their ad...lol.


Ps...I do agree with you that the CDH should work on any of these, I just can't stand it that the Chinese instructions and descriptions are total contradictory garbage when they try to translate it into English.

Yeah, alot can be lost in translation, especially between languages that have nothing in common. The cdh is pretty so ill order it. I'll probably get that one later and do a comparison, but for now I'll just order the cdh.

 

[Jayraye39]

Thought about a reed valve. But they often have problems like more places for air to leak and replaceing the peddles. Think im gonna try and squeeze as much as i can with the piston port setup. Only after I hit a wall will I look at a reed and bigger carb. With this setup my next power uprgrade will be correcting transfer angles and case stuffing

 

[Jayraye39]

Bike looks rad, but not running an air filter will hurt power/efficiency from air buffeting in and out will mess up your carb signal

Since my bikes are only ridden on the street ive opted for less restriction and run only the stack. Ive ran the stack by itself for 3 years now and have never had a problem. But you claim more power gain with running a filter? Thats new to me please explain your reasonings if you dont mind.