Power loss, speed loss and high fuel consumption.

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pxc-in-japan
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Power loss, speed loss and high fuel consumption.

Post by pxc-in-japan »

This question is about my other scooter, not my PCX.
Can I ask it here?
If not, sorry, I guess an admin will move this.

I have the three problems stated in the title.
(2008 Suzuki Address V125G Japan model)

Changed CVT belt/rollers 8,000 kilometers ago, at 26,000 kilometers.
Changed spark plug, oil and filter, air filter 3,000 kilometers ago (frequently changed).
Taken CVT system apart. Looks OK and clutch not at service limit yet.
Brakes cleaned and adjusted (not sticking).
Tire condition and pressure OK.
Bike is ridden quite gently.
About to take air-intake-to-throttle body assembly off.
Might be dirty throttle valve but doubtful at 34,000 kilos on a serviced bike.
I will also check the crank case breather is not clogged and check the valve clearances.

Questions
1. Can I use engine conditioner to clean the throttle valve or MUST it be 'Throttle cleaner'?
2. What else can I safely use for throttle valve if dirty?
3. Any other causes come to mind?

Thanks
http://www.fuelly.com/motorcycle/honda/pcx150/2015/staninjapan/408151]Image
pxc-in-japan
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Re: Power loss, speed loss and high fuel consumption.

Post by pxc-in-japan »

Crank case breather hose is clean.
Spark plug is not fouled.
Air filter is clean.

It seems that 'engine conditioner' does not clean throttle valves, though.
http://www.fuelly.com/motorcycle/honda/pcx150/2015/staninjapan/408151]Image
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Re: Power loss, speed loss and high fuel consumption.

Post by homie »

Should go straight to simple compression test. You can eliminate rings and valves right off.
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Re: Power loss, speed loss and high fuel consumption.

Post by pxc-in-japan »

homie wrote:Should go straight to simple compression test. You can eliminate rings and valves right off.
OK thanks.
Not used any more.
Sits under a cover on my drive but I would like to have it right.
Only 33,000 kilo / 20,00 mile on it, with very frequent oil changes at about every 3,000 kilo, so likely not a compression problem I think (but I am a DIY mechanic only).

I will see if that can be done cheaply by one of my students who is a pro mech.
I have no tools for that.
http://www.fuelly.com/motorcycle/honda/pcx150/2015/staninjapan/408151]Image
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Re: Power loss, speed loss and high fuel consumption.

Post by you you »

pxc-in-japan wrote:
homie wrote:Should go straight to simple compression test. You can eliminate rings and valves right off.
OK thanks.
Not used any more.
Sits under a cover on my drive but I would like to have it right.
Only 33,000 kilo / 20,00 mile on it, with very frequent oil changes at about every 3,000 kilo, so likely not a compression problem I think (but I am a DIY mechanic only).

I will see if that can be done cheaply by one of my students who is a pro mech.
I have no tools for that.

If it's not used regularly and has a carb I'd be looking at checking/cleaning that first.
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Re: Power loss, speed loss and high fuel consumption.

Post by Mel46 »

If it has been sitting for some time and has a carb, clean the carb and put additive in the gas tank. How old is the gas that is in It? You may need to remove the old gas and add new gas after cleaning the carburetor with some carb cleaner. The additives in gas start separating after a while of sitting. You can also get condensation in the tank that can cause rust on the inside of the tank. Hopefully a good cleaning and new gas will do the trick.
Currently own:
Red 2013 Honda PCX150

Givi tall windshield & tailbox - Lots of extra lights
Custom seat from Thailand - Bad Boy Airhorn
Takegawa Lowering Shocks - Michelin City Grip Tires
Headlight assy upgraded to LEDs w/HS5 main bulbs
NCY variator, drive face, and rollers
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Re: Power loss, speed loss and high fuel consumption.

Post by fish »

Testosterone.
It's low. They have a patch.
You're welcome.
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pxc-in-japan
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Re: Power loss, speed loss and high fuel consumption.

Post by pxc-in-japan »

you you wrote:
pxc-in-japan wrote:
homie wrote:Should go straight to simple compression test. You can eliminate rings and valves right off.
OK thanks.
Not used any more.
Sits under a cover on my drive but I would like to have it right.
Only 33,000 kilo / 20,00 mile on it, with very frequent oil changes at about every 3,000 kilo, so likely not a compression problem I think (but I am a DIY mechanic only).

I will see if that can be done cheaply by one of my students who is a pro mech.
I have no tools for that.

If it's not used regularly and has a carb I'd be looking at checking/cleaning that first.
Fuel injection, not carb, but thanks.
Reckon it might be the air-intake pressure sensor, but cannot remember now how I came to that tentative assumption.
It has been sitting unused since, and not before the problem developed.
As per earlier in this post, I fitted new CVT belt, rollers and dampers (plastic vario side pieces) and cleaned and inspected all other CVT parts inc the clutch and all are clean and in great conditiopn according to the dealership that sold me / services my Suzuki V-Strom.
I am (tentatively) convinced for the time being that it is not a CVT / drive train issue, but a fuel / air feed / electronic control issue.
http://www.fuelly.com/motorcycle/honda/pcx150/2015/staninjapan/408151]Image
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Re: Power loss, speed loss and high fuel consumption.

Post by pxc-in-japan »

Mel46 wrote:If it has been sitting for some time and has a carb, clean the carb and put additive in the gas tank. How old is the gas that is in It? You may need to remove the old gas and add new gas after cleaning the carburetor with some carb cleaner. The additives in gas start separating after a while of sitting. You can also get condensation in the tank that can cause rust on the inside of the tank. Hopefully a good cleaning and new gas will do the trick.
Almost certainly not that but thank you.
Please see just above / just below in this post, thanks.
http://www.fuelly.com/motorcycle/honda/pcx150/2015/staninjapan/408151]Image
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Re: Power loss, speed loss and high fuel consumption.

Post by E. Foster Salsbury »

All signs point to a valve being to tight. If one valve cannot close all the way during the compression stroke you lose power and thus increase fuel consumption.

34,000 km is a good time to do a valve check. Were they ever checked?
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