What's The Diagnosis: Easy Edition

JHScoot · Post by **JHScoot** » Fri Oct 05, 2012 2:19 am

My scooter is a 125cc Kymco Agility. It starts perfectly all the time. Except recently if not started for over 2 days it takes several tries to start. It doesn't cough or backfire or do anything in particular. Opening the throttle seems to do nothing, although it MIGHT have something to do with it eventually starting? I don't smell gas when trying to start it.

The weather has been hot but the bike is always cold when it does this, first start of the day. And again, after sitting two or three days.

Bike has been serviced within 2000 miles, runs like a champ. It's two years old, 9000 miles. It would be nice just to know what I can check, look for first, and to know what i am looking for?

Thanks!

Lostmycage · Post by **Lostmycage** » Fri Oct 05, 2012 2:22 am

Test your battery. They typically last about 3 years.

JHScoot · Post by **JHScoot** » Fri Oct 05, 2012 2:25 am

awesome. i thought of that but its reassuring to hear from someone taking an educated guess

that will be my first foray and i am eager to hear from anyone with a "if it isn't the battery check......" advice

BuddyRaton · Post by **BuddyRaton** » Fri Oct 05, 2012 2:48 am

Carburated? Sounds like a bad float needle

jrsjr · Post by **jrsjr** » Fri Oct 05, 2012 3:45 am

Page 21 of the Kymco Agility 125 Service Manual has a flowchart for troubleshooting hard starting or non-starting. I mention this because it's a handy backstop in case it actually turns out to be something non-trivial.

I vote with LMC to suspect your battery first. Pull that bad boy out and get it checked at the Battery Store or some such place where they have serious battery diagnostic equipment, not just a voltmeter, because the situation you describe is exactly the kind of problem that a voltmeter test will NOT detect.

Good luck!

MGM · Post by **MGM** » Fri Oct 05, 2012 1:58 pm

I'm not familiar with Kymco, but I assume it's a GY6 type of scooter. If so they have a temperature controlled auto choke on the carb. If that isn't working if could affect cold start. I am not aware of a way to test/check.

BeefSupreme · Post by **BeefSupreme** » Fri Oct 05, 2012 3:13 pm

If it's anything like my Like200i, some came with loose connections on the solenoid posts. Seems to be somewhat common, and super easy to fix. Just snug em up. Mine wouldn't engage the starter but 1 in 8 tries sometimes, then boom, it would start right up. After tightening the connections I haven't had the problem since.

jrsjr · Post by **jrsjr** » Fri Oct 05, 2012 3:18 pm

MGM wrote:I'm not familiar with Kymco, but I assume it's a GY6 type of scooter. If so they have a temperature controlled auto choke on the carb. If that isn't working if could affect cold start. I am not aware of a way to test/check.

JHScoot, a bit of terminology , if you look at the troubleshooting flowchart I mentioned above, the manual refers to the auto choke as the "auto bystart." It's mentioned toward the bottom of the flowchart. Of course, since it's electric, it's also shown on the schematic, page 1-20, where it's referred to at the "auto b/s."

tortoise · Post by **tortoise** » Fri Oct 05, 2012 4:02 pm

JHScoot wrote:It would be nice just to know what I can check, look for first, and to know what i am looking for?

Unclear if the electric starter is energizing properly? If the issue is carb related . . might try accessing the carb through the bottom seat tub door, rotating up the carb overflow tube (page 1-18 in previous referenced service manual), and spraying in a couple shots of carb cleaner. The gas-cleaner mixture in the carb fuel bowl may be strong enough to dissolve pilot jet and "choke" passageway obstructions (if that is the issue).

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az_slynch · Post by **az_slynch** » Fri Oct 05, 2012 5:02 pm

There's already a lot of good troubleshooting in this thread, but one of your comments caught my eye.

JHScoot wrote:Opening the throttle seems to do nothing, although it MIGHT have something to do with it eventually starting? I don't smell gas when trying to start it.

Modern carburated scooters with a gravity-feed fuel system have a vacuum operated fuel tap. There's a vacuum line that runs from the tap to a fitting on the intake manifold. When the engine is cranked over at startup, prior to starting, manifold vacuum is lower than it would be when the engine is running. Keeping the throttle closed keeps a higher vacuum pressure in the intake and engures that there is enough suction to keep the fuel tap open until the engine starts (at which point there's plenty of manifold vacuum to open the throttle and keep the tap open).

JHScoot · Post by **JHScoot** » Fri Oct 05, 2012 8:22 pm

great! all this info is fantastic and not just a help for me but anyone on the 'net with similar issues. so keep 'em coming although this thread is fruitful already!

i will be tackling this when i have time this weekend. its nice to know where and how to start, though. and i do have a shop manual jrsjr and will be going through the troubleshooting section as you say. but just looking at it without real world advice and guidance? for me its a bit daunting. so the good stuff from you and others "in the know" about these things from experience is most valuable =]

jrsjr · Post by **jrsjr** » Fri Oct 05, 2012 10:40 pm

JHScoot wrote:..and will be going through the troubleshooting section as you say. but just looking at it without real world advice and guidance?

The thing is, the best mechanics are handy with tools and have experience, but, at the end of the day, they're mentally running through those flowcharts, too and combining that with experience, observation and a little intuition. The secret is to be thorough. Don't skip, for example, the battery load test we've suggested, or you can drive yourself crazy running around and around in circles and never find the problem.

As I said before, good luck!

Modern Buddy

What's The Diagnosis: Easy Edition

What's The Diagnosis: Easy Edition

Re: What's The Diagnosis: Easy Edition

Re: What's The Diagnosis: Easy Edition