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Wayne S.
Wayne S., Motorcycle Mechanic
Category: Motorcycle
Satisfied Customers: 1255
Experience:  Experienced and Licensed Motorcycle Mechanic - all sizes and brands welcome.
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I have a 1988 yamaha xv250 (route 66). The bike started up

Customer Question

I have a 1988 yamaha xv250 (route 66). The bike started up fine and I rode around for a while, then stopped it but now it wont start. It turns over but will not start at all. I had the carburator, "fuel pump" and spark plugs replaced. It keeps turning over as if it wants to start, but just wont. What major problem should I look for?
Submitted: 1 year ago.
Category: Motorcycle
Expert:  Wayne S. replied 1 year ago.


Pull a spark plug and see if it is wet/dry/oily or sooty.
You need compression which can be affected by overly
tight valve clearance, also proper fuel supply and good spark.
See if the spark to the plugs is strong blue or other.
You can also try some carb cleaner or starting fluid
in the rear of the carbs to see if it will fire on that.
Use starting fluid sparingly though.
Let me know what you find.
Customer: replied 1 year ago.
The spark plugs are new, they were just put in but ok. is that it? It couldn't be a bad starter or coil? The headlight turns off when I try to start it.
Expert:  Wayne S. replied 1 year ago.
Does the engine sound like it is spinning normal
starting speed? If not the battery could be weak.
If you have spark then the coil is okay.
Lay the spark plug against the engine with
the wire connected and see if it sparks when
starting the engine. If the spark looks good
then you might have fuel or compression problems.
Let me know what you find.
Expert:  Wayne S. replied 1 year ago.
As far as the headlight turning off that can be normal
as long as the battery is good. Many bikes have
a starter button that disables the headlight temporarily
so the starter gets more battery power for starting.
Just make sure your battery is good or turning the engine
over normally.
Customer: replied 1 year ago.
Thanks the engine sounds as if it's trying to start normally but it just wont. More this weekend.
Expert:  Wayne S. replied 1 year ago.
Okay, thanks. the spark plugs are new but still check
them to see what the engine is doing. Wet means flooded,
dry might be lack of fuel, oily is bad rings, sooty
means lack of air, like a plugged air filter.
The plugs can help you to find the problem.
Customer: replied 1 year ago.
Thanks, ***** ***** sense!
Expert:  Wayne S. replied 1 year ago.
Good luck checking things out, valve clearance
is set at .003" for intake and .004" for exhaust
when the piston is at the top on compression stroke.
Usually there is a line for the rear and two lines
for the front cylinder on the timing marks.
Customer: replied 1 year ago.
It's been raining so we haven't yet had a chance to check yet. Will keep you updated. :-)
Expert:  Wayne S. replied 1 year ago.
No problem, check it carefully to eliminate errors, thanks.