The Honda PCX / Forza / ADV150 / SH Forums

I checked my clearances for the first time at 4000 km.
They were both a little tight but still good:
IN .09mm
EX .23

I have set them to:
IN .10 (exact)
EX .26 (loose end)

I havent put the tupperware back on, will in a couple hours. Should I get both valves exact or slightly loose? I dont want to check it again for as long as possible.

The PCX has screw-type adjusters, knocking on the valve stem ends 3000 times per minute (50 times
per second) at cruising speed. This hammering between tiny surfaces gets only worse with loose
clearances. I wouldn't set them too loose...

My Forza has clever little shims on top of the valve stems. I adjusted them on the loose end when new, no problem as that arrangement can take it, and makes adjust. intervals much longer.

As you noted, valve clearances tend to tighten up with time. More so with the PCX , and mostly
during the first few thousand miles -- Honda recommends a rather early valve adjustment
on the PCX for that reason.

With intakes set at a meager .004", how long would a PCX last without needing an adjustment,
I don't know (my Forza's tightened only by .001" or so in 15000km, a very good sign). In fact,
I decided to buy it the minute I became aware of its valve setup -- shims can be changed in 10
minutes, and set on the loose side.

How much time did it take to remove the damned plastics btw ? It will become a dull routine
with time, don't worry...

Cheers for the info. I left the clearances as is and figure I'll do it again later if it sounds bad.
Will be interesting to see how they fare in some thousand km.

The plastics took a loong time to get off. especially as its my first time. watched some youtube during removal, took about 3hrs. snapped a couple little tabs but looks like it'll live without. The time it takes is my only gripe with the scoot.

Fired it up. runs well. change the oil tomorrow and go for a ride..

I also broke some tabs on mine, then filed them down so that it wouldn't show. I even willingly broke
some others, or modified their shapes, so that the plastics are now easier to remove/fit back. It now
takes me about 15 minutes to access the engine (twice that to carefully fit them back), a vast
improvement.

Mine is a Forza 300, but the same should apply to the PCX -- the damned plastics are so tight-fitted
from the factory they are almost impossible to remove (I was lucky not to scrap some the first
time I decided to have a look under the seat)

wow. 15 mins is very quick. i dont think its possible to do removal on a pcx in less than an hour.

i feel a great sense of achievement and relief checking the valves, especially after skipping it at the first service.

dick,

The PCX is pretty, and good. But is a pita to work on, isn't it.

Before the Forza, had the Smax : all that was needed to remove to have the valve cover jump
into your face was 4 screws+ a small cover...took about 30 seconds once I had rounded out that
cover's tabs. I miss that.

aguim wrote: The PCX is pretty, and good. But is a pita to work on, isn't it.

yep.

Smax looks pretty good too. We don't get them in aus

I wrote a thread for the dismantling of the PCX and the valve clearances.
However, my valves did not need adjusting, so I put it all back together.
Lovely.
However, as they did not need adjusting, I did not loosen the nuts to adjust them.
I was happy about that, as I could not see how I would have adjusted them if I had needed to.
Once the locking nut is loosened, what tool / method would you use to actually turn the tiny little head of the valve assembly?
It's a tiny little square-shaped thing.
Pliers?
Finger tips?

Thank you.

pxc-in-japan wrote: Once the locking nut is loosened, what tool / method would you use to actually turn the tiny little head of the valve assembly?
It's a tiny little square-shaped thing.
Pliers?
Finger tips?

Thank you.

Finger tips are fine, pliers are fine. Just be gentle, they're tiny little parts.

maddiedog wrote:

pxc-in-japan wrote: Once the locking nut is loosened, what tool / method would you use to actually turn the tiny little head of the valve assembly?
It's a tiny little square-shaped thing.
Pliers?
Finger tips?

Thank you.

Finger tips are fine, pliers are fine. Just be gentle, they're tiny little parts.

I use any square screw found on RV , mobil homes fasteners. Fairly common in and around the RV industry

I have PCX150v1 (2012)
The first time I checked valves on 12000km- it was fine (according to spec- no need to adjust)

But also I'm a mechanik and check valves on not mine PCXs (according manual at first 1000km)- usually it is LED models, and I want to tell- most of them NEEDS to adjustment at first 1000km already...

Vancho wrote:I have PCX150v1 (2012)
The first time I checked valves on 12000km- it was fine (according to spec- no need to adjust)

But also I'm a mechanik and check valves on not mine PCXs (according manual at first 1000km)- usually it is LED models, and I want to tell- most of them NEEDS to adjustment at first 1000km already...

On average, how much is the clearance off by? I assume they are too tight.

Rickjds wrote:

Vancho wrote:I have PCX150v1 (2012)
The first time I checked valves on 12000km- it was fine (according to spec- no need to adjust)

But also I'm a mechanik and check valves on not mine PCXs (according manual at first 1000km)- usually it is LED models, and I want to tell- most of them NEEDS to adjustment at first 1000km already...

On average, how much is the clearance off by? I assume they are too tight.

Sorry I don't records particular numbers, but usually there is too loose in valves

maddiedog wrote:

pxc-in-japan wrote: Once the locking nut is loosened, what tool / method would you use to actually turn the tiny little head of the valve assembly?
It's a tiny little square-shaped thing.
Pliers?
Finger tips?

Thank you.

Finger tips are fine, pliers are fine. Just be gentle, they're tiny little parts.

Right, thanks.
I wonder how tricky the exhaust valve is to do being on the 'underside' of the head, as it were.
There is a special tool mentioned in the manual which for some reason I did not notice first time around.
Using that, the feeler gauges and the locking nut is going to 'fun' until I get used to it.

Purchased my PCX from a small town dealer that likely does not sell more than two a year. It is hard to imagine how they make any money servicing the limited number they sell, as stated above, removing the body panels is a pita.... Having a factory manual is a must for these rigs, wow. Both valves seemed a bit snug for my liking but then getting a straight, level approach to the gap was tough. Before all the panels were removed, I started to entertain the thought of looking for an area where I could cut a section of body panel out and put in place an access door. I value convenience over cosmetics. Try as I might, it appeared the 'Full Monty' is the mandate. Like many, even with care, I managed to break a clip or two. At least doing it myself afforded me that insight. Doubt if any shop notes on your receipt how many clips they break. Nice to have a little adjusting tool.
...

Getting back to easyrider about that square head screw, was in Texas 46 years ago and was looking for a
Robertson screw driver to fix some rinky dink thing on my VW van. Was informed that was a " Canadian screwdriver and I was shit out of luck. One guy at a pawn shop had one and I was on my way.
Never thought of reverse engineering that the 4mm square head on the PCX valve adjuster could be the same as one of those " Canadian screws"

I personally use 0.1mm and 0.15mm for intake and exhaust respectively. It's nothing, because my engine is fairly open, not like on a pcx, my scooter is an offspring of the pcx, so setting them at the loose end makes the valves tick enough to annoy me so I set them at those value. No significant drop in power, but quieter.