KymcoForum.com
Scooters - 125 to 300 => Agility 125 => Topic started by: Vision on July 15, 2023, 04:01:17 PM
-
This morning I'm running an errand in an area of town with rough roads/bumps. On the way back on a perfectly flat smooth road going a steady 20mph suddenly the power to the rear tire ended (like I had let go of the throttle) and I was coasting and idling. I gave it throttle but nothing changed. While coasting and moving the throttle back and forth a few times the power to the tire reengaged.
A few minutes later the same thing happened but after going over a speed bump.
A few minutes later it happened again while on a flat road.
Then when close to home I hit a bump and this time the engine died. After pulling over and waiting a moment it started back up again and I was able to make it home.
The fuel filter doesn't look dirty. Should it be replaced anyway?
The drive belt was replaced recently but there was no jerkiness to indicate the belt was having trouble engaging.
-
Don't have a cristal ball, but:
- my first suspect would be the renewed belt and CVT clutch
(many years on the shelf, too long, too small, and so on...)
- next would be coil, sparkplug cable, cap and plug itself, somehow loose...
- then I would check fuel and air system
This is to be found.
-
I'm thinking something electrical is going on... like a loose sparkplug cap/wire. Ground cable loose/dirty. Battery cable (s) loose.
Stig
-
I am with loose electrical...
-
Anyone think it could be the cdi?
-
Yes, could be a faulty CDI too, but start with inexpensive checking.
-
Anyone think it could be the cdi?
Do what Ruffus said! Don't start throwing parts at the problem!
-
Agreed. I'm traveling the next few weeks and can't get at the bike, am thinking of ordering spare parts in the mean time.
-
Hey All, I'm embarrassed to say I think the problem was due to a spark plug needing to be replaced and its cap was knocked a little loose.
I usually replace the Iridium plug each spring after putting about 8k km on it a year. This spring I read that the plug can go something like 60k km before needing to be replaced so I didn't replace it. Does anybody else go through plugs like this?
-
One nil to the Mighty Stig!
-
Agreed Neil.
-
Hey All, I'm embarrassed to say I think the problem was due to a spark plug needing to be replaced and its cap was knocked a little loose.
I usually replace the Iridium plug each spring after putting about 8k km on it a year. This spring I read that the plug can go something like 60k km before needing to be replaced so I didn't replace it. Does anybody else go through plugs like this?
Iridium plugs last much longer then regular plugs. Had an Denso Iriduim on my scoot for over 30000km, on my motorcycle (NGK Iriduim) they lasted over 50000km.
Changing it every 8k km is just a waste.
-
Just saying, I only get 8k km out of mine.
-
I vote "loose electrical".
Spark plugs rarely need changing. In the "old" days when we had leaded gasoline they would need cleaning due to the lead deposits on the electrodes, or fouling from an oil burning cylinder. Garages had sand blasting machines that cleaned plugs.
Iridium plugs last at least 50,000 miles due to the use of an iridium electrode, which has an extremely high melting point and doesn't burn away like the old steel electrodes did and which required periodic re-gapping. Platinum electrode plugs are long lasting, too, but apparently iridium is the latest winner in the high price spark plug market.
-
I use Shell Rotella T6 synthetic 5W-40 diesel engine oil and add 2oz of Techron to the gas tank at every oil change. Is it possible these are creating high temperatures that are eroding the Iridium plugs?
-
I use Shell Rotella T6 synthetic 5W-40 diesel engine oil and add 2oz of Techron to the gas tank at every oil change. Is it possible these are creating high temperatures that are eroding the Iridium plugs?
No.
please send all your worn out iridium plugs to me. thank you.
-
Yes the plug needed to be replaced.
-
Would be interesting to see such a plug. If possible take a pic and post it please.
I'm using iridium plugs since years on several vehicles and didn't have such a problem.
Oily yes, but was caused by carb (too rich). Never had an eroded middle electrode. (pls see pics)
These plugs are from one of my GUZZIS taken out after ca. 20.000 kms.
As you can see the right one ran a little bit hotter, having this little specks of baken fuel on it..
Seen on the other pic, there was no eroding in this case.
-
Yes the plug needed to be replaced.
Interesting.
Do you have a picture of one of them?
Iridium plug tips never deteriorate, the ground electrode wears out, but that takes a lot of km.
-
As for adding a fuel additive to the tank every fill up , maybe give some thought to using only a top tier fuel.
Fuels labeled at the pump as Top Tier have all the cleaning and protection additives necessary for any modern engine. TT fuels cost no more than other fuels.
Give a read to TT fuels....and who recommends them.
One less thing to worry about 🙂
Stig
-
Stig, you got me thinking about the top tier fuels so I did a local search...interesting that only the Conoco and Phillips 66 stations are on the list (and they are few and far between, but Cosco is on the list). Most of our available gas is at convenience store chains (Casey's, Kum & Go, Kwik Star).
Looks like top tier fuels must meet a minimum level of deposit control additives and must not contain organo metallic additives that can harm emissions equipment.
The retailer pays a fee to the marketing group to be able to display the Top Tier logo. What bothers me is that the non 'top tier' fuels may be just as good, containing the same level of additives but they haven't paid the marketing fee or had the testing done to get the approval?
Similar to some oil companies and approvals on engine oil..if you don't pay for the certification you don't get it...but you may be just as good...hmmmmm...
I do wonder about the fuel quality in much of the world where these scoots are sold in much larger numbers than in the tiny US market.
I guess with top tier you know they've passed the test..with the others you hope they have but don't know.
-
It's hard taking good pictures of the plug.
(https://images2.imgbox.com/1c/90/2d6uFfwL_o.jpg)
(https://images2.imgbox.com/64/4b/vlwbLdHe_o.jpg)
(https://images2.imgbox.com/e5/5c/lxn8JhjZ_o.jpg)
-
Interesting to see, seems like eaten off this electrodes upper tip. Saw this on standart plugs but until now, not on iridiums.
My hypothesis would be that, somebody tried to tap the clearance, demaged this tip and compustion did the rest.
Iridium has a melting point of above 2200°C, such temperatures are never reached in a motor.
Cannot think right now of something else as a cause.
Fuel and additives also might not cause that.
-
Thanks. I have no reason to think the plug was physically damaged since this life expectancy is normal for plugs in my scoot.
-
Stig, you got me thinking about the top tier fuels so I did a local search...interesting that only the Conoco and Phillips 66 stations are on the list (and they are few and far between, but Cosco is on the list). Most of our available gas is at convenience store chains (Casey's, Kum & Go, Kwik Star).
Looks like top tier fuels must meet a minimum level of deposit control additives and must not contain organo metallic additives that can harm emissions equipment.
The retailer pays a fee to the marketing group to be able to display the Top Tier logo. What bothers me is that the non 'top tier' fuels may be just as good, containing the same level of additives but they haven't paid the marketing fee or had the testing done to get the approval?
Similar to some oil companies and approvals on engine oil..if you don't pay for the certification you don't get it...but you may be just as good...hmmmmm...
I do wonder about the fuel quality in much of the world where these scoots are sold in much larger numbers than in the tiny US market.
I guess with top tier you know they've passed the test..with the others you hope they have but don't know.
Shell, Sunoco, Mobil around my town. Lots of them. Have yet to find a reason not to use TT fuels. Price is the same. Others not bothering to be certified is not my concern 🙂
I use the Shell Super 93 in everything but the cars.
Turns my mower into a hovercraft!
Stig
might have made up some of this....
Nasty looking plug!
Too much additives....or really lousy gas?
-
Nasty looking plug!
Too much additives....or really lousy gas?
I only use Shell 93 and the Techron a few times a year.
-
I only use Shell 93 and the Techron a few times a year.
With the Shell , you'll not need any additives.
Wrong heat-range spark plug?....because it sure seems like something strange is going on to do this routinely to your plugs.
Stig
-
Wrong heat-range spark plug?....because it sure seems like something strange is going on to do this routinely to your plugs.
Stig
I don't think so, it's the NGK (7544) CR7HIX Iridium IX Spark Plug.
-
Maybe it's the Shell Rotella T6 synthetic 5W-40 diesel engine oil.
-
One spark of suspicion came in my mind:
Little bit farfetched but...
-all sparkplugs with an "R" in its code have an built in resistor of 5 ohm, be it iridium or other
- if you have a sparkplug cap which has also a built in resistor of 5 ohm, resistance cumulates to 10 ohm and might show such a picture
Maybe we do have an electric engineer within here, who could go into this theory to say possible or nonsense?
-
-
That's interesting Ruffus. This is the coil, maybe it's running the plug hot.
https://www.amazon.com/Performance-Ignition-Scooters-Sandrail-Coolster/dp/B00N2HG57K
-
Dunno, to be honest. It's guesswork like a lot with this, our scoots. But could be a nail on this iridium coffin.
-
Maybe it's the Shell Rotella T6 synthetic 5W-40 diesel engine oil.
a friend is a former Toro commercial lawn mower sales rep. He says nearly everyone uses the wrong kind of engine oil in their mowers. This is an air cooled engine 4 stroke not a diesel. and if your cap is loose like you mentioned that would be another concern. Doubt the plug is the problem. Small air cooled engines need different additives than a diesel engine does. My mp3 400 revs quite high, over 5000 rpm and needs a certain kind of oil. Dont' see why the kymco 125 wouldn't do better with motorcycle oil. or something better suited than diesel oil. Diesels don't rev very high.
-
T6 is popular with scooter, ATV, small engine owners so I started using it about 10 years ago.
-
T6 is popular with scooter, ATV, small engine owners so I started using it about 10 years ago.
diesel engines have no spark plug so maybe oil designed generally for diesel is part of the problem. I am a late comer to this area of engine maintenance so I will add a link to what I am currently reading for anyone who is interested. I am sure many of you are already aware of this material.
https://www.mototribology.com/articles/jaso-explained-part-1
-
The evidence from the many and long-time Rotella users here, strongly suggests that the Rotella is not causing his problem.
Stig