Bound to happen

[CROSSBOLT]

Hope this helps, it's step by step manual for valve clearance Kymco downtown 300i

https://imgur.com/a/4YtWVZV

That's it! Good description, good pitchurs! Take your time and enjoy! Lock nuts don't have to be super tight. Those are really fine threads plus that stuff is super hard.

While you are in there, inspect cam and roller surfaces and make sure the rollers roll!

[moparkid]

Might have solved the problem. Apparently while tightening down the lock nut the adjustment bolt also tightened past the point of the feeler gauge....shoulda double checked my work before reassembly. Battery drained so it will charge tonight and we'll have another go at it tomorrow! Live and learn aye....Will keep everyone in suspense for another day!

[Neil955i]

Sounding promising though!

[moparkid]

Rechecked valve lash, triple checked! All is well there. Checked kickstand, unhooked it from system and bike would not even turn over so kickstand circuit is good. Checked injector, sprays while trying to twist her tail, so injector is good. Ran EFI self diagnosis check, all seems well. Not getting any strange lights on the dash. Starts, runs for 15-30 seconds and shuts off.....Could be faulty fuel pump? Seems that if it were electrical it would not even start or run. Unknown sensor I am unaware of?

[CROSSBOLT]

Rechecked valve lash, triple checked! All is well there. Checked kickstand, unhooked it from system and bike would not even turn over so kickstand circuit is good. Checked injector, sprays while trying to twist her tail, so injector is good. Ran EFI self diagnosis check, all seems well. Not getting any strange lights on the dash. Starts, runs for 15-30 seconds and shuts off.....Could be faulty fuel pump? Seems that if it were electrical it would not even start or run. Unknown sensor I am unaware of?

You did pretty well at eliminating usual suspects. Doubt an unkown sensor not showing a code.
You have a good idea about fuel pump. There would be no code by running out of fuel. Rig up a pressure gage on that line going to the injector and see if the pressure drops when engine quits. Have you checked voltage when either starting or running?

[moparkid]

Update:

Ran CELP self diagnosis after changing plug. Old plug's south end had been eaten away by faulty plug cap, which had been held on to the plug for years with a zip tie due to the fact I couldnt seem to get a new plug cap. Once installed bike ran until I shut it off. Then I ran CELP self test and am getting 06 and 09 reading which suggests faulty TPS and faulty MAP. Then I ran into an even greater problem...,.Kymcopartsonline has gone dark! Oh my....where will I ever get the needed parts???

[Stig / Major Tom]

Update:

Ran CELP self diagnosis after changing plug. Old plug's south end had been eaten away by faulty plug cap, which had been held on to the plug for years with a zip tie due to the fact I couldnt seem to get a new plug cap. Once installed bike ran until I shut it off. Then I ran CELP self test and am getting 06 and 09 reading which suggests faulty TPS and faulty MAP. Then I ran into an even greater problem...,.Kymcopartsonline has gone dark! Oh my....where will I ever get the needed parts???

To clarify.....scooter now runs fine, in spite of seeing codes?!-  - except you want to buy a new spark plug cap?
Would one of the many NGK park plug caps sold on amazon and eBay work?


Stig

[moparkid]

No Stig, my bad. After putting in new plug, bike ran until I shut it off....Then tried to restart, ran 30 seconds and shut off....I think having a corroded half eaten south end of old plug prevented CELP from operating as it should. Once I tried to restart then the CELP light flashed 6, then 9 times. Ran it three times and it still spit out 6 and 9. I might be mistaken by what my meaning of plug cap is...my meaning should be spark plug "boot" and not cap, as in threaded piece on south end of plug. I found Powersportswarehouse has kymco parts and ordered a new MAP, TPS sensor and a coil ignition assy. I hope I have clarified previous post.

Well it looks like Powersportswarehouse is no longer stocking kymco parts.....guess I might have to go to Taiwan and get the parts huh......

[CROSSBOLT]

No Stig, my bad. After putting in new plug, bike ran until I shut it off....Then tried to restart, ran 30 seconds and shut off....I think having a corroded half eaten south end of old plug prevented CELP from operating as it should. Once I tried to restart then the CELP light flashed 6, then 9 times. Ran it three times and it still spit out 6 and 9. I might be mistaken by what my meaning of plug cap is...my meaning should be spark plug "boot" and not cap, as in threaded piece on south end of plug. I found Powersportswarehouse has kymco parts and ordered a new MAP, TPS sensor and a coil ignition assy. I hope I have clarified previous post.

Well it looks like Powersportswarehouse is no longer stocking kymco parts.....guess I might have to go to Taiwan and get the parts huh......

6 long then 9 short CELP flashes or 6 short pause 9 short? Bet it's both short. Have you tested both TPS and MAP as per service manual?

[moparkid]

All flashes were short and 06 with picture of engine and 09 with picture of engine shows up on dash. I have not tested either sensors, will get around to that tomorrow....baby steps...lol

[CROSSBOLT]

OK, waiting to hear what you find!

[An Orange Crush]

Well after 60,000 miles my sweet baby has decided to leave me stranded by the side of the road. Today I did a full blown maintenance of the bike...oil and filter, tranny fluid, air filter replacement and valve adjustment. Got out on the road and it was performing better than ever....that should have been a red flag right there!

An hour into the ride she started cutting out and then she died. Would not restart immediately but after sitting for about 20 minutes started right up but would die after a minute or so. Managed to get it back home and this morning it started right up but died after 3 minutes and wouldnt start again. But an hour later started right up, but then again died after a minute or so. Sounds like a fuel problem to me but have no idea where to begin.

I know you'll read this Karl and I await your expertise!

Thank you!

My 2012 DT300 was just having the same issue and I was able to limp it home. The first thing I went for was the spark plug and immediately noticed that it wasnt very tight. I am the one who put it in there about 10,000 miles ago. It looked just fine so I put it back in, started it up and the problem was gone in my case.
I have 19,000 miles on mine.

[moparkid]

Finally made contact with someone in Taiwan who is going to get me my parts.....my only concern is the TPS on order is a  1614-868-0000 in the parts diagram but the one they are sending is a 1614-868-0000-S.....does anyone know what or why there would be a different part number? Would there be different TPS's for different countries?

[CROSSBOLT]

Finally made contact with someone in Taiwan who is going to get me my parts.....my only concern is the TPS on order is a  1614-868-0000 in the parts diagram but the one they are sending is a 1614-868-0000-S.....does anyone know what or why there would be a different part number? Would there be different TPS's for different countries?

Guessing don't KNOW) the "S" is different supplier. You will KNOW when you get the new one in a side-by-side comparison. Meanwhile, why don't you unplug the ECU, goober up the connector with silicone dielectric grease and plug it back in. Try your start-run-stop-start test again. Better yet, goober every electrical connector on the bike while at it!

[moparkid]

Are we talking removal of a lot of plastics to get to the ECU?