The Honda PCX / Forza / ADV150 / SH Forums

Since I switched back to stock, my engine was running rich all over, power output was lower too, and the most annoying thing is difficulty to start after long periods of resting the scooter.
I have tried almost everything, you name it. I bet you I had tried it. I literally changed everything from the crankshaft (my old crankshaft was oil starved somehow and got loose), new cylinder, piston, valves, new cylinder head and yes I have lapped my valves, right valve clearance, I even changed my oxygen sensor out of the fear that over 6000km of a carburetor setup may have contaminated it, everything back to stock. Well except for one thing.
As I have used Yuminashi injector in the past, and I have lost my stock injector that comes with my scooter from the dealer in the first place, I sourced one injector from a friend of mine, that injector comes from another 125cc 10 inch wheel eSP scooter from Honda, the LEAD125. I thought all 125cc injectors were the same. Boy was I wrong. I bought a new injector that is for my specific scooter model and guess what it starts and runs normally ever since. I have tested it for 3 days and I'm absolutely sure all my problems are solved .

LESSON: If you upgrade to a big bore kit, KEEP YOUR STOCK STUFFS SOMEWHERE SAFE. It will help you a lot if you need to switch back to stock for any reason. Don't be stupid as I was, losing the stock stuff, although I run a stock engine now I still appreciate the power a good big bore kit can offer. In fact I'm working on a Yuminashi 62mm project as of now .

Cheers.

Absolutely! One should keep all the stock engine parts when upgrading because someday you'll get tired of it and want to bring everything back to stock.

After three years of using a customized camshaft and a big carburetor on my small 110cc yamaha, I finally got tired of the speed that I install all the stock parts back.

Keep em somewhere and don't forget to oil or clean them once in a while too.

This is good advise, I keep every swapped nut, bolt, mirrors, seat, the stock rollers, variator parts etc. All could be returned to stock except the cropped tail for the big license plate support... that's gone forever. The next owner might appreciate my upgrades but then again maybe not, so yes keep that stuff stored away in a cool dry place.

Based on my calculations, if you follow the service manual and change oil, coolant frequently the pcx engine should last over 60000km without losing much power and compression. I have just rebuilt one pcx engine at 62k km and everything looks ok, not as good as new but you can get by. The pcx engine over here is cheap as f*ck, I changed the bottom end (crankshaft) and the entire top end including new cylinder head, valves, piston etc 100% with 250$.

BPT7594 wrote:Based on my calculations, if you follow the service manual and change oil, coolant frequently the pcx engine should last over 60000km without losing much power and compression. I have just rebuilt one pcx engine at 62k km and everything looks ok, not as good as new but you can get by. The pcx engine over here is cheap as f*ck, I changed the bottom end (crankshaft) and the entire top end including new cylinder head, valves, piston etc 100% with 250$.

Where are you from?

alx123 wrote:

BPT7594 wrote:Based on my calculations, if you follow the service manual and change oil, coolant frequently the pcx engine should last over 60000km without losing much power and compression. I have just rebuilt one pcx engine at 62k km and everything looks ok, not as good as new but you can get by. The pcx engine over here is cheap as f*ck, I changed the bottom end (crankshaft) and the entire top end including new cylinder head, valves, piston etc 100% with 250$.

Where are you from?

Vietnam. Where Honda makes the engine. 250$ is the price for the crankshaft, cylinder, piston, rings, cylinder head, valves, camshaft, valve spring. And that's Honda prices.

BPT7594 wrote:

alx123 wrote:

BPT7594 wrote:Based on my calculations, if you follow the service manual and change oil, coolant frequently the pcx engine should last over 60000km without losing much power and compression. I have just rebuilt one pcx engine at 62k km and everything looks ok, not as good as new but you can get by. The pcx engine over here is cheap as f*ck, I changed the bottom end (crankshaft) and the entire top end including new cylinder head, valves, piston etc 100% with 250$.

Where are you from?

Vietnam. Where Honda makes the engine. 250$ is the price for the crankshaft, cylinder, piston, rings, cylinder head, valves, camshaft, valve spring. And that's Honda prices.

Great. Lucky you.

Those who lives from other countries where parts are rare and expensive should heed the advice I think. Also, some parts won't be available anymore after a few years..

well Honda parts are usually available all the times. That's the silver lining of buying a Honda bike/scooter.