| Chinese scooters suffer from some of the
worst press ever imagined. Most of it isundeserved and propagated by
those unwilling to take the time to figure out whats going
on. Here, we'll detail a couple of the oddities and what
you can do to work with these affordable and fun vehicles.
Some of the most common problems with these are listed
here. But first a warning: we CAN NOT fix/diagnose your scooter over the phone.
Unless you're mechanically inclined, you shouldn't
be working on the bike in the first place. More scooters have
died because the wrong people 'fixed' them than anything
Spark Plugs - they're garbage, usually Torch
or LD, and we will replace them as soon as we take them
out of the box with quality NGK plugs. You should too;
we have the plugs, just drop by. Most of the two strokes
seem to come with decent plugs, so this is mostly a 4
Fuel Filters - the Chinese don't
add Ethanol to their gas, because they're not crazy and
driven by oil politics.The fuel filters shipped with
some scooters are paper element type and fall apart with
ethanol gas, and the goopy bits of paper end up in your
carb. We use ethanol friendly metal core filters.
Valve Clearances - often set poorly at
the factory, these tend to go out of adjustment in the
early miles (under 500) of many of these bikes. This has
lead to the premature death of many a good bike when people
don't properly understand this very basic problem. It's
sometimes a time consuming job to do, but once done, rarely
needs doing again for a long while. The trick is knowing
what to set these to, which we can do for you.
Carburetors - these mainly suffer from
things we do to them, they're usually copies of Keihin
designs and sometimes Walbro's (50cc). The auto chokes
crap out occasionally, but not nearly as often as
people will tell you, it's often a misdiagnoses of
something else. The jets in these tend to block up with
our volatile and fast to evaporate ethanol containing
gas. The previously mentioned fuel filter problems don't
help one bit.
Gas Tanks - More ethanol bashing. Being
as ethanol absorbs water over time, when it sits in your
gas tank for more than a few months it can cause rust
problems. Bikes with external gas caps
suffer most because people leave them in the rain and
water gets in through the key hole and seals. Gas treatments
like Stabil can help, especially if you're not using your
ride regularly (once a week at least). The petcocks (fuel
valve) can also cause problems. They can stick open, possibly
flooding your motor or they can stick closed, obviously
stopping fuel getting to the engine. Or worst of all, the
lines can crack and allow a vacuum leak to your
Tires & Wheels - Generally, these are
problem free, but the alloy wheels on some are easily cracked
and bent, but this goes for all scooters and motorcycles.
Hit a curb or big pot hole and it'll cost you. A bigger
problem is valve stems; they dry rot (at least
here in the south) and either leak or can pop out at speed! This mostly happens through neglect, being left outside
on unused for long periods.
Oil Leaks - The engines need oil! Four
strokes need it inside the engine, not on your driveway.
Check this regularly, it takes five seconds and we're
happy to show you how to check it. Two strokes need oil
in their oil tanks - and not lawn mower, marine, engine
oil, vegetable oil or any other garbage you find - they
need motorcycle specific two-stroke oil ! We have it.
Some even smells like Strawberries, I kid you not. Put
the wrong stuff in here and your engine will not last
Engines - Most chinese scooters use a
few basic engines; lets start with the 50cc class and work
up from there. 50cc four-stroke: 99% of these are based
on an engine called a QMB139 GY6. Reputed to be an
old Honda design from the 80's that was stolen
and cloned, it is possibly one of the most popular motors
in the world. The story of how it came to be cloned is
well documented in industrial engineering circles. The
easiest way to identify if you've got one of these is
to look for a raised area on the bottom left of your engine
with the 139 number somewhere. The 39 portion is the bore
size of the motor in mm. These motors can easily be improved
on by upping capacity to 80cc - a kit we're happy to fit
to your scooter.