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Engine lost power

Posted: Wed Feb 08, 2017 6:34 am
by crashcrew84
Going to work 25 mile in to the ride bike had a small hesitation as I slowed to pull off the Hwy at the end of 1.5 mile at 55 mph most of the trip is 40 to 45 mph, run 30 mph up to a stop sign pull off get to about 35 mph power lost the sound goes flat like a bog if I open the throttle fast it bog like its not getting fuel putt the last 2 mile to work. Pull the plug its reads lean. Check fuel flow 2 oz in 10 sec install new pump and injector (do valve adjust with fuel tank off 1st adjust still in speck) Its better but still not running right will still bog out if I open the throttle fast but can easy right up to 50 mph. New plug, just did the belt drive a three weeks ago.
Bike is just over 61000 miles oil change is every 1300 mile The exhaust has been looking hot the last few months head pipe turning gray and a band around middle of the muffler like it has been hot after about 7 mile ride last night head pipe was around 320 to 370 degree the mid part of the muffler was 470 degree.

Re: Engine lost power

Posted: Wed Feb 08, 2017 7:00 am
by tomtomclub2005
If you have 61000 miles on your pcx i beleive you won the contest of the biggest mileage on a pcx...

Re: Engine lost power

Posted: Wed Feb 08, 2017 7:19 am
by easyrider
Plugged exhaust pipe.. run with no exhaust as a test and see. Go from there

Re: Engine lost power

Posted: Wed Feb 08, 2017 9:02 am
by homie
didn't seat the spark plug connection all the way?

Re: Engine lost power

Posted: Wed Feb 08, 2017 3:16 pm
by tomtomclub2005
homie wrote:didn't seat the spark plug connection all the way?
If I understand well, he checked the plug after getting his prob. So problem was there before. Maybe the Kat in his muffler is clogged. who knows...

Re: Engine lost power

Posted: Wed Feb 08, 2017 3:41 pm
by crashcrew84
Was thinking about the Kat melting when the fuel was lean and blocking off part of the exhaust going to run a PSI check on the motor and maby scoop the top end.

Re: Engine lost power

Posted: Wed Feb 08, 2017 10:59 pm
by Gil
Check for exhaust leaks. Additional oxygen in the exhaust will mess with the O2 sensor reading leading to a bad fuel mixture. A overly rich mixture will overheat your cathalytic converter, causing it to melt and clog your exhaust.


Gil

Re: Engine lost power

Posted: Thu Feb 09, 2017 3:37 pm
by you you
Air filter

Re: Engine lost power

Posted: Thu Feb 09, 2017 4:31 pm
by DAB
Check battery and connection.

Re: Engine lost power

Posted: Thu Feb 09, 2017 11:20 pm
by crashcrew84
Update Compression test came in with 140PSI so down 5. Scoop of the top end every thing look good no erosion from the lean burn or damage to the valves. tested the TPS and it checks out good. the color on the spark plug looks good nice light tan.
The bike stalled down one time on my way to work today would not get over 35 or more that 1/2 throttle.
Did it to the mec when he tested two times then it just started to pull right up to 60 mph and could not get it to acted up.
Air filter is less than 2000 miles old same for the belt and drive system as was the spark plug has a new plug now.
Thinking damage to the exhausted any one have a used stock muffler cheep.

Re: Engine lost power

Posted: Fri Feb 10, 2017 10:27 am
by Mel46
Could you be kind enough to enter your location in your profile so that we can get a better understanding about your environment, please? Sometimes the riding environment makes a difference, and certainly it makes a difference in who could best help you with parts, etc.

Re: Engine lost power

Posted: Tue Feb 14, 2017 7:31 pm
by maddiedog
Looks like Eastern NC.

I would look on Ebay. You can also get one new (aftermarket) from Thailand for fairly cheap, but it will take months to arrive.

Make sure you get the right exhaust for your PCX, the 2011 had a normal and an eSP configuration. The 150 exhaust is different too.

Re: Engine lost power

Posted: Tue Feb 14, 2017 11:27 pm
by k2apache6.0
I have a stock exhaust for a 2013 esp with just 2,500 miles on it, and a good cover too, it's quite heavy, so shipping it could be expensive though.

Re: Engine lost power

Posted: Tue Feb 28, 2017 8:45 pm
by crashcrew84
A for what its worth update about 900 mile with out a hiccup on a side note the PCX was starting to use oil before pump failing I was adding about 1 Qt each month just before changing the fuel pump the past month it has only used less than 3 oz.
So If your PCX starts to use oil with no sign of burning it or leaking you may need to have your fuel pump tested

Re: Engine lost power

Posted: Tue Feb 28, 2017 9:28 pm
by homie
crashcrew84 wrote: If your PCX starts to use oil with no sign of burning it or leaking you may need to have your fuel pump tested
Good to know... thanks for follow up

Re: Engine lost power

Posted: Tue Feb 28, 2017 9:46 pm
by iceman
Out of interest, if the oil is not leaking away or burning off but you lose large amounts - why would the fuel pump be the culprit (just wondering from a tech perspective how that works) :)

Re: Engine lost power

Posted: Tue Feb 28, 2017 10:27 pm
by homie
iceman wrote:Out of interest, if the oil is not leaking away or burning off but you lose large amounts - why would the fuel pump be the culprit (just wondering from a tech perspective how that works) :)
It wouldn't but come on... we got a follow up on a tech thread :lol:

Re: Engine lost power

Posted: Wed Mar 01, 2017 3:38 am
by Pcxdemon
But seriously, if you want to check on your fuel pumping abilities, just pull off the fuel line of the injector and place the line in the small bottle then try cranking the motor. It will squirt fuel, quite a bit of it. Then you'll know fuel pump is ok..

Re: Engine lost power

Posted: Wed Mar 01, 2017 6:27 pm
by Gil
Update crashcrew84?



On a side note, my scoot lost power a couple of weeks ago due to a dragging rear brake. Might be something to check for.
one last thing, does your bike really have 60,000 miles on it?

Re: Engine lost power

Posted: Wed Mar 01, 2017 6:59 pm
by PCX150Rider
Air filter is less than 2000 miles old same for the belt and drive system as was the spark plug has a new plug now.


I had an intermittent problem that was driving me crazy starting on my 49cc 2-stroke at around 4,000 miles and it ended up being a "whiskered plug". The crap in the electrode was literally welded in and I couldn't flick it out of the gap. Just replaced the plug with a new one and good to go. I couldn't complain. . .it was a cheap fix. Then the carburetor float needle started giving me some problems and I was getting raw gas in the air filter cover. It could have also been a defective auto-cock (gravity fed fuel system to a carb) also but more likely the carb. So I cut to the chase and put an inline on/off valve just before the carburetor and leave it shut off when I'm not using it and turn it on when I'm riding. It can also double as a stealthy theft deterrent. . .they won't get that far. . .have to carry it eventually. . .oh well. :lol:

Not saying that's your problem but didn't you say you replaced the air filter and belt and plug around 2000 miles ago as new? Or was the plug like really new just after this bog issue started. . .like in the "now". Even new spark plugs can get cracks in the porcelain if they are not installed properly or just "Murphy's Law" kicks in.

I apologize for wasting your time with this post if it really was a brand new plug you put in just recently or something and that's definitely not the problem.