Colin, I never heard of a weld failure on a scooter, and only a few incidents on dirt-bikes and owners admitted that they were jumped.
I agree that with some brands, wiring and and general assembly can be problematic - loose or cross-threaded bolts, no grease in joints, bad crimp joints, improper vacuum/fuel line routing, bad hoses and connections, air bubbles in brakes and coolant, etc.
Your experience will depends on the brand and who you are buying from, but most major Chines OEMs have pretty good QC and components (CFMoto, JMStar, Linhali, Lifan, Zongshen, QingQi, Shinray, etc). The problem is private label importer - they seem to have zero interest in preserving they reputation and always go to the lowest bidder, specing bottom-end compomnents. The only exception for private label that I know of is Qlink.
I have an 07 Lifan 200cc dual sport bike that I bought new. It now has 8700 km on the clock and runs great. It did have a few minor assembly glitches that I discovered when setting it up from the shipping crate. Nearly no grease in the wheel bearings and suspension pivots. No oil on the foam air filter. Noisy front brake pads. Misrouted wiring. All easily fixed but it shows poor quality control at the assembly stage.
Overall I really like the bike and have no doubt it will last many years. I paid less than 1/3 the cost of a similar new Japanese bike.
Scooters are getting more and more popular. I purchased a 2005 Tank Touring Deluxe 150cc for $800 with only 85 miles. I spent less than $40 in maintenance in a litte over a year. Insurance was about $92 a year and I spent about $8 a week on gas.
I only had one small electrical problem which was my own fault. I tightened the mirrors too tight without moving the mirrors away from the wires. Other than that it didn't give me any other problems. I saved time everywhere I went because I could just cut to the front of the line at stop lights. I also added an MP3 CD player with Ipod plug in, and some HID headlights to be seen better at night. It was definitely a comfortable ride.
I sold it a couple weeks for $1200 with about 5K miles and I bought myself a sportier 2007 Tank 150cc with 16" wheels for $1300. Although it's faster than my old 150, I want a 250cc Reflex clone like Cat's for freeway use, so my 150 is now up for sale.
I believe that if you keep a "cheap Chinese scooter" well maintained, it will last a long time. There are some on Scootdawg forums that have well over 10K miles on their Chinese scooters and their still running strong.
The last Italian vehicle I owned was a Fiat 128. An execrable P.O.S. that cost me a fortune in repairs, and nearly killed me by running out of gas prematurely. The primary carb throat iced up, made the car only run on the rich secondary, and stranded me west of Ottawa one frigind January night.
But I have to admit that I'm fascinated with Aprillia's fuel injected two stroke 50 cc scooters. They time the injection so there is no smoke and much better FE than any carburetted two stroke.
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