Powerloss

[Aero]

Hello

I am a new user to this forum, all the way from Norway 

My ZX50 has started to loose power. The engine seems to be running fine, and when the scoot is left on the stand, everything works as normal. The problem is with hills. When travelling uphill, the scooter does not have enough power to get me to the top. The engine is still running, but no forward motion.

Do you have some pointers as to what the cause of the problem can be ?

Thanks

[sidthesloth]

G'day Aero, welcome to the forum, lots of info and fun here. There are a lot more experienced here than me but it sounds like your cvt needs some attention, check your drive belt and variator rollers for wear and also check your clutch while you are there. How many kilometres on your scoot?

[thebatman]

good morning/ good evening....not sure which.      welcome to the forum areo..... with that it sounds like you need to take off the belt cover and check your belt....check the belt, rollers for flat spots...it may be good idea to change belt, rollers, for sure. that alone will make an improvement for you.... what yr zx do you have?....any mods done......yet?...

[Aero]

Hello.

Thanks for the feedback. My scoot is a 2005 model, and it has only run 5800 km, so almost new :-)

I have checked the cvt, but no obvious errors to be seen, but then, I am no mechanic. Could the problem be related to the carb ? The engine runs perfectly when it has no load, but after a short periode of transporting me, it almost dies if I do not step off.

Hope the explanation makes sence :-)

[sidthesloth]

That is very low kms for that kind of problem, have you had a look inside your exhaust and exhaust port on your cylinder? Maybe a build up of carbon restricting the gas flow. When art comes on line, he will give you a better idea of what to look for.

[sidthesloth]

Oh, I forgot to ask, does it splutter at all? if so, it could be the air filter needs cleaning.

[art]

  I would agree clean air filter carb and put in a new plug if it still acts the same than might be time to replace the belt and rollers, Hard to say what rollers are in there now maybe going a hair lighter will help on those hills,but if not running right it wont matter what you do,
  It's common for the bike to perform o.k. on the stand and completly different under a load. Take note of the plug and main jet size when doing your basic tune up,It can help out if more changes are needed. Good luck!

[Aero]

Thanks for all the good tips from the kymco experts :-)

I will start with changing the sparkplug and see if it helps. The airfilter was my first thought, so I have tried to run it without filter, but this did not change anything.

Yes, it does splutter sometime, but not all the time :-)


I can't really make this out. The scoot worked perfectly on my way home from work. I left it outside for about one hour, and then when I was going out for a new ride, it started to act up, and has not been itself since.

[Aero]

A dealer said the problem might be moisture in the carb. Do I have to take the whole thing apart, or can it be drained somehow ? I have the service manual and can see a drainage plug on the carb. Can this be used ?

The scoot is all original, no mods yet, but I am tempted to make some mods once I get it running again. It is not the fastest scoot :-)

[art]

  Yes there is a drain screw on the float bowl and should have an overflow hose at the bottom.Try to catch the run off and look for some water droplets,this will deffinatly make your bike act up. Got some gas from a local shell station a few weeks back that left me about a teaspoon full of water in the float bowl. Did not run well at all,may want to do a full carb clean at this point anyway.

[sidthesloth]

+1 to what art said. I know what you mean about not being fast, mine is not fast, but it is the fastest zx in town.

[Hoolander2]

If it's still running you should be able to cure it by putting some Seafoam or Startron in the gas tank and run it.  YOu won't have to take anything apart.  Startron is at Walmart in the marine section.  Oh and keep using it right along.

[Aero]

Hello again.

The scoot is still running, but not good  . I changed the sparkplug, and drained the carburettor. This did improve the situation a bit, but not much. I am able to run the scoot, but uphill I only reach 10 km/h, and about 25 on the flats. Seems the rpm is not getting up. If I hold the throttle at max, the engine slowly dies.

Could this indicate a problem with the fuelflow, so the next step would be to take the carburettor apart ? How big a job is this for a novice mechanic ? I am afraid to break something :-)

I have ruled out the airfilter since running without airfilter did not change the situation at all. Could the airflow to the engine be clogged after the airfilter ?

What is Seafoam or Startron ? We don't have Walmart in Norway :-)

[sidthesloth]

Seafoam is a fuel stabiliser and cleans the system, I have not used it myself but it is suppose to be very good. It sounds like your carb will need a clean. have you done a compression test? That may tell more.

[Hoolander2]

You could have more water in the gas tank.  It is no use to clean the carb if more water keeps coming in from the tank and or petcock.  Drain tank and carb both at the same time and refill with good gasoline.  Or, find a fuel additive that you can pour in. 

Also, clean the small vent in the fuel cap.