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Scooters - 125 to 300 => Downtown 300 => Topic started by: moparkid on April 15, 2019, 03:07:19 PM

Title: popping sound at high speed over 50
Post by: moparkid on April 15, 2019, 03:07:19 PM
Got a problem folks! Got up and went for a ride and then stopped and filled up with gas at Valero, where I seldom if ever get gas. Ran great and is running great other than it sounds like there is a popping sound at high speeds. Thought it was my helmet strap slapping up against my helmet but that isnt it. Could be backfiring but it could also be bad gas? Valve adjustment? Runs great other than the popping sound. Thanks!
Title: Re: popping sound at high speed over 50
Post by: CROSSBOLT on April 15, 2019, 06:40:18 PM
Not a clue except for the gas. I stopped using gas from both Citi and Valero in 2009 when I found that Hugo Chavez of Venezuela owned them. Their sales have been poor since so there is probably water and who knows in their stuff. My opinion. Your mileage may differ....
Title: Re: popping sound at high speed over 50
Post by: moparkid on April 15, 2019, 11:23:45 PM
I hear you on that Karl. I have always used Shell or Chevron and only because I was out in the sticks and wasnt sure how far I could go on a flashing low fuel indicator I made the error of filling up at Valero. Guess I will just add a few bottles of injector cleaner (rocket fuel) and run it out. Thanks!
Title: Re: popping sound at high speed over 50
Post by: Stig / Major Tom on April 16, 2019, 02:05:07 AM
Yes, but meanwhile no more high speeds until Hugo's gas is gone. That noise cannot be good for the engine.

Stig
Title: Re: popping sound at high speed over 50
Post by: moparkid on April 16, 2019, 03:57:42 PM
Well like always my initial diagnosis was WAY OFF!..lol....A few years ago (maybe less, maybe more, at this age who knows!) I dropped the bike when dodging a car changing lanes, and apparently the rear fender had also sustained damage that I didn't catch when assessing the damages for insurance purposes. It appears that three out of the four hold down screw mounts for the rear fender had been damaged and only one bracket was keeping the fender in place. It finally gave way and for that day only the fender was just riding and bouncing off the rear tire. The way I figured it out it was not a mechanical/fuel issue was while driving 65 mph and hearing the popping I shut off the motor to coast and the popping never stopped until the bike got down below 35 mph. I guess I should be glad the fender didn't jam up into the spoke of the rear tire and cause a major accident. So now after looking at kymcoparts.com I located all the replacement parts needed to fix it and it's all under $60 total. But now I question the need for that rear fender since I never ride in the rain. Thanks to you guys for input. But we're back on the road...minus a part or two but hey, we be ridin!
Title: Re: popping sound at high speed over 50
Post by: stuo on April 16, 2019, 11:34:00 PM
When I wash my scoots I wiggle the parts that are most likely to vibrate loose and finger turn/check the attaching bolts and screws. I recently caught the exhaust pipe cover on my DT300 that had lost one fastener with the other almost off.  Locktite to the rescue! I had to chuckle at the forum member who thought someone had "stolen" his pipe cover when he saw it was missing.
Title: Re: popping sound at high speed over 50
Post by: moparkid on April 16, 2019, 11:59:21 PM
good idea Stuo...I'll keep that suggestion in mind when doing maintenance and washings.
Title: Re: popping sound at high speed over 50
Post by: Tromper on April 17, 2019, 12:12:33 AM
The rear fender also deflects rocks & debris so adds a degree of politeness to those behind ya & probably saves some other plastic from damage as well.
I'd replace it, but then I'm fussy.

...But now I question the need for that rear fender since I never ride in the rain. Thanks to you guys for input. But we're back on the road...minus a part or two but hey, we be ridin!
Title: Re: popping sound at high speed over 50
Post by: CROSSBOLT on April 17, 2019, 01:03:54 AM
Well like always my initial diagnosis was WAY OFF!..lol....A few years ago (maybe less, maybe more, at this age who knows!) I dropped the bike when dodging a car changing lanes, and apparently the rear fender had also sustained damage that I didn't catch when assessing the damages for insurance purposes. It appears that three out of the four hold down screw mounts for the rear fender had been damaged and only one bracket was keeping the fender in place. It finally gave way and for that day only the fender was just riding and bouncing off the rear tire. The way I figured it out it was not a mechanical/fuel issue was while driving 65 mph and hearing the popping I shut off the motor to coast and the popping never stopped until the bike got down below 35 mph. I guess I should be glad the fender didn't jam up into the spoke of the rear tire and cause a major accident. So now after looking at kymcoparts.com I located all the replacement parts needed to fix it and it's all under $60 total. But now I question the need for that rear fender since I never ride in the rain. Thanks to you guys for input. But we're back on the road...minus a part or two but hey, we be ridin!

Har, har! Do- do do occur!
Title: Re: popping sound at high speed over 50
Post by: moparkid on April 17, 2019, 05:17:15 PM
Already ahead of you Tromper...ordered the necessary parts from a kymcoparts.com and will replace the fender and you make a fine point about road debris.