PCX150 Power Curve

[Mgalutia88]

A takegawa cam is cheaper than their exhaust. It will give you the power your looking for. It's less that $200 shipped. If your careful I believe you can swap it with the engine installed. I believe it's a 1.5 hp increase.

[wingz]

While searching for the Takegawa camshaft, I stumbled upon a proper power curve for the PCX.
Looks like it is for a PCX125 with vs without camshaft.

1202_pcx_ports_camshaft_e.pdf

(176.62 KiB) Downloaded 211 times

Any links to Takegawa camshaft for PCX150?

[wingz]

This looks interesting: http://www.yuminashi.com/pcx150-esp-camshafts/

[Mgalutia88]

The Yuminashi cam should be more powerful as Takegawa is designed a little conservative and Yuminashi is designed for maximum performance. The difference here is that the Takegawa cam could be installed by itself while the Yuminashi cam requires stiffer valve springs and different rocker arms, an addition of roughly 100 euros to the price. I believe it comes out to be about $50 more expensive in the end.

[wingz]

I believe you lose the decompression feature when using the Yuminashi camshaft.

Who here has installed the Takegawa camshaft?
Are there any drawbacks?
Do the PCX125 and PCX150 use the same camshaft?

[Mgalutia88]

Pcxdemon has the Takegawa cam installed. Takegawa lists different cams for the pcx 125, pcx 125 esp, and pcx 150 esp.

The decompression feature is a factory feature on models with idle stop to ease the stress and voltage use on the starter. Those of us that don't have idle stop don't get the decompression feature anyway.

[wingz]

I thought the decompression feature was on all the models to assist starting in general.

[Alibally]

I thought they recommended a higher capacity battery due to the higher compression when starting or did I just imagine that?

[wingz]

Quite correct.

[Mgalutia88]

Then I stand corrected. I still don't see much use for it in my case. I usually don't ride less than 8-10 miles between shutdowns. In my case I don't have the idle stop. Still you do bring up the fact that it was a design feature in all models. This makes me think more about which camshaft to purchase. Hmm. Back to the factory microfish.

[wingz]

I would imagine a single cylinder 4-stroke engine quite tough to start without some decompression.
The PCX starts beautifully.

[Mgalutia88]

So researching the takegawa vs yuminashi camshafts I find that the takegawa is roughly $150 plus shipping and the yuminashi cam plus the required rocker arms and springs comes to $275 plus shipping. Not that I wouldn't want the extra power of the yuminashi cam however I'm not interested in spending double the money...

[Mgalutia88]

Also yuminashi and takegawa list the same part numbers for both esp models. I found this interesting.

[wingz]

This is interesting.
We also don't have power 150 curves for either Takegawa or Yuminashi.

[Mgalutia88]

Nope. I'll check and see if the 125 esp and 150 esp have the same cam p/n from honda. That could be interesting also.

[waspmike]

So researching the takegawa vs yuminashi camshafts I find that the takegawa is roughly $150 plus shipping and the yuminashi cam plus the required rocker arms and springs comes to $275 plus shipping. Not that I wouldn't want the extra power of the yuminashi cam however I'm not interested in spending double the money...

So the question is why the new rocker arms? Springs are easy they are stock Honda parts, at least here. Also from a different thread Taka retains the decompression for start up. Is there any evidence for "extra" power?

How do they compare to "normal" ones?

Cam lift :

#1 - 280 degrees, 5.5 mm ,

# 2 - 330 degrees, 6.0 mil

[Mgalutia88]

What are these specs? 125 vs 150? Intake vs exhaust? Takegawa vs yuminashi?

[waspmike]

What are these specs? 125 vs 150? Intake vs exhaust? Takegawa vs yuminashi?

These are from a local Thai website for PCX150i.

They are to different grinds one. Different companys use different terms but given the way cams are classified I would say one 280 duration and one 330. It doesn't say if intake and exhaust are different, they are probably the same.

As an example on a Vespa LX150 the old Vespa Soho hot cam was both valves 264 duration with a 7.4 mm lift.

I'm no expert but would offer that in car parlance the 280 is a rally cam and the 330 a race cam. If your variator is set to 8000 and red line is what 9600, then you are only working with 1600 rpm so the 330 one would probably be ok. For "everyday" riding the 280?

[Mgalutia88]

Okay I understand that part I'm familiar to cam duration and lift and lift at .050 specs are different also. But what are you saying? The 280 duration is the takegawa spec and the 330 duration is the yuminashi spec?

[waspmike]

Okay I understand that part I'm familiar to cam duration and lift and lift at .050 specs are different also. But what are you saying? The 280 duration is the takegawa spec and the 330 duration is the yuminashi spec?

No I'm not saying either. My numbers come from a site or company that offers two different camshafts for a 150i PCX. They are simply different grinds

Why limit ourselves to two. It's like Monty Python. How many sexes are there? Two. Its not enough we need more.

Either of the two will show you a flashy picture with statements like.

"It feels like 150cc+ and I achieve same acceleration of stock Pcx with only 1/4 throttle"

or "camshafts are designed in conjunction with our racing efforts, and in turn the design gets passed down to our customers for the best power gains"

The second one is interesting as the Internet is woefully missing any pictures of PCX racing. Unless of course all the racing is at night on unused roads in which case it is drag racing.

It doesn't hurt to publish cam specs as no one is going to rush out and produce cams with one or two degrees difference.

Just buy a camshaft and tune your variator to it. Or not...In any level of motorsport engines will have different cams and be tuned accordingly. One wins one day, another another day there is no absolute.

I'm starting to sound like GN2 here but it is not intentional