Hard starting when cold
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Hard starting when cold
When I got my NB50 it started easily, but it had no power after a few minutes.After many weeks of frustration such as numerous carb cleanings and elcetrical checks I replaced the reed valve and it solved that problem.Now the bike is hard to start after replacing the reeds.Not sure what could have caused it to hard start just by replacing the them?Checked to make sure everything is correctly installed.One thing that is weird is that if I park it for a day and then try to start it will start easily, but if it sits for a few days it is hard to start.Very strange problem.I tested this a few times and it does this everytime.Thought maybe I have a compression issue.Could it be the crank seal of a bad head gasket?
85' Aero
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Wheelman-111
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- Location: Deepinnaharta, Texas
Hard Cold Starting
Greetings:
How does it run once it's started?
The symptom you describe is typical of carbs fed by a vacuum-controlled petcock. The fuel in the bowl evaporates down in a few days - the carb is vented so as to permit gravity flow to fill the bowl. It takes several seconds of cranking time to pull vacuum on the petcock, then several seconds to refill the bowl to operational level. All those hoses Honda-san had put on the carb to control evaporation are long-gone by now.
Check your vacuum lines for cracks and iffy fit at the barbs. You can test for yourself by sucking - er, applying vacuum with an EPA approved vacuum application device (of course after donning all appropriate PPE) for a few seconds and see if it starts the way it does after 1 day sitting. I had cobbled something up using extra line and a windshield-washer 1-way valve to have a hose under the saddle to suck - er,... you know... - after a week away from Scootage. Noiseguy or someone was going to make some kits - USPMale? - for sale but I haven't heard anything in several months.
How does it run once it's started?
The symptom you describe is typical of carbs fed by a vacuum-controlled petcock. The fuel in the bowl evaporates down in a few days - the carb is vented so as to permit gravity flow to fill the bowl. It takes several seconds of cranking time to pull vacuum on the petcock, then several seconds to refill the bowl to operational level. All those hoses Honda-san had put on the carb to control evaporation are long-gone by now.
Check your vacuum lines for cracks and iffy fit at the barbs. You can test for yourself by sucking - er, applying vacuum with an EPA approved vacuum application device (of course after donning all appropriate PPE) for a few seconds and see if it starts the way it does after 1 day sitting. I had cobbled something up using extra line and a windshield-washer 1-way valve to have a hose under the saddle to suck - er,... you know... - after a week away from Scootage. Noiseguy or someone was going to make some kits - USPMale? - for sale but I haven't heard anything in several months.
Wheelman-111
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
Re: Hard starting when cold
thanks-I will give it a try.I never saw gas evaporate that fast that the bowl would get low in acouple of days.It always seemed to have plenty of gas in it.
85' Aero