The Honda PCX / Forza / ADV150 / SH Forums

brought 2010 pcx sunday and started doing service on oil and coolant etc and then today decided to check out gearbox and behold


I just took off the fill nut from gearbox and it just shot out old black sludge oil I was like wtf

so im guessing old owner as some how overfilled it and never replaced it since they owned it

so I drained it all out and put castrol power1 racing 10w30 oil in

is this fine to use castrol power1 racing 10w30 as its fully oil jaso ma as they also work with wet clutch which should do fine for gearbox

Wow - I can't see how it could ever get that overfilled. Good thing it was on your hit list.

I am no expert, but your oil choice seems perfectly fine to me. I think most of us just use what didn't go into the oil change as the fluid for the gearbox.

also I checked belt as it felt it was holding back and it was full of cracks like its never ever been replaced but the rollers where new so im confused by previous owner didn't do belt aswell lol

already did oil and coolant as I didn't trust the stuff they used for it

this is problem with second hand you don't know if its been looked after and then could lead you spending money but lucky enough I got it cheap so its worked out good for me

Nice going by checking it over.

ye I was shocked to see it being slimy and sludge surprised it didn't cause damage to the gears inside unless it will down the line maybe cause bearing failure but I guess I see

accyuklad wrote:brought 2010 pcx sunday and started doing service on oil and coolant etc and then today decided to check out gearbox and behold


I just took off the fill nut from gearbox and it just shot out old black sludge oil I was like wtf

so im guessing old owner as some how overfilled it and never replaced it since they owned it

so I drained it all out and put castrol power1 racing 10w30 oil in

is this fine to use castrol power1 racing 10w30 as its fully oil jaso ma as they also work with wet clutch which should do fine for gearbox

I’m just shocked that there is a fill nut on the PCX and oil shoots out of it.

Now if you’d removed the drain bolt and oil “shot” out of it it wouldn’t be sludge.

The warning signs are there....

I heard that some Forza 125 had some failure to the gearbox bearings due to the too low level of oil in gearbox.
Some dealers recommended to overfill a little by leaning the bike to the opposite side.

So when i change my gearbox oil on my pcx, i always fill to the max (160ml on v3 or 140 ml on v4) then lean the bike and add 20ml before putting the screw back. Maybe it's not really necessary, but as it's not an engine, a little more oil to lubricate cannot hurt

I didnt tried to open the filling screw first, but i guess it will flow if i did !

And i use the same oil as the engine, 10w30 or 5w30

Givestrong wrote:I heard that some Forza 125 had some failure to the gearbox bearings due to the too low level of oil in gearbox.
Some dealers recommended to overfill a little by leaning the bike to the opposite side.

So when i change my gearbox oil on my pcx, i always fill to the max (160ml on v3 or 140 ml on v4) then lean the bike and add 20ml before putting the screw back. Maybe it's not really necessary, but as it's not an engine, a little more oil to lubricate cannot hurt

I didnt tried to open the filling screw first, but i guess it will flow if i did !

And i use the same oil as the engine, 10w30 or 5w30

Interesting. I change mine with every engine oil change because 1 US quart will exactly fill both. I just first drain the final drive and then fill it back up with a syringe thru the fill (doesn't take much until it starts to overflow), and the rest goes in the crankcase (which fills up completely).

accyuklad wrote:ye I was shocked to see it being slimy and sludge surprised it didn't cause damage to the gears inside unless it will down the line maybe cause bearing failure but I guess I see

Good call to change all of the fluids on a new-to-you machine! If it were mine I'd probably do another gear oil change after 500-600 miles of riding to help flush out any crud that remained after your first change.

That 10w30 will work great.

If it was that bad, I'd do another drain and fill, as Eiron recommended.

I'd also keep an eye on the level long-term, it is possible water got in there somehow if it was that full.