Honda Spree and Elite 50 Forums

Even though my bench test of the bystarter showed the barrel/needle moving about 1/8" when 12v was applied (indicating a properly functioning bystarter), I tested the bystarter air circuit with the syringe. When the bystarter is cold, air will flow through the circuit when air is squirted in. When 12v is applied and the bystarter heats up, air will flow through the circuit. The air flow test indicates that my bystarter is not closing off the circuit when it should. So...conflicting test results. Also, the scoot is difficult to start if it sits for a couple days and it seldom seems to "fast idle" when cold. If the bystarter is stuck in the open position, cold starting should not be an issue. Comments?

Hi, difficult to start after a few days seems to be a common issue. I think what's happening is the carb empties over a few days due to evaporation and that includes the bystarter chamber in the float bowl. I found that turning the engine on the starter for a few seconds to allow the petcock to let fuel into the carb, then leaving things for about 20 seconds it will then start as per normal.
No idea about the bystarter circuit, perhaps 1/8" is not enough?

I have a brand new Polini in mine and I will experience this after letting it sit for a week. All I do is give it a couple kicks from the kick start, then turn on the key and hit the starter button and it fires right off every time. Even on the coldest days. But then, I use a manual choke on mine, not an auto choke. Love the manual choke. I use a remote extender cable so I don't have to reach down to engage/disengage it. I'll never go back to a bystarter. With a manual choke, you don't have to second guess anything, and you can disengage it when YOU feel like it, not when a potentially defective bystarter feels like it.

We all know how 2-strokes work, right? A mixture of oil and fuel enters the crankcase, the fuel ignites in the combustion chamber and the residual oil lubricates EVERYTHING inside the crankcase...Crank bearings, lower/upper rod bearing, cylinder walls, etc.... Oil is tossed around and essentially coats every nook and cranny when the crank is spinning and the piston is jumping like it just stepped on a Lego barefoot. Once everything is beautifully lubed up and you STOP the motor, what happens to all that sweet lube that has made everything so slickery?.....over time it finds its way to the bottom of the case ever so slowly. Its not an excessive amount but enough to create a "hard start" situation. Once the motor finally fires, the lovely oil at the bottom is vaporized or simply forced out of the exhaust port until your mixture stabilizes and you have ignition. Hence the big smoke plumes when you cold start.

Thats my lesson for the day. Late assignments will be graded at half credit. Quiz on friday.

mikehailwood wrote:Even though my bench test of the bystarter showed the barrel/needle moving about 1/8" when 12v was applied (indicating a properly functioning bystarter), I tested the bystarter air circuit with the syringe. When the bystarter is cold, air will flow through the circuit when air is squirted in. When 12v is applied and the bystarter heats up, air will flow through the circuit. The air flow test indicates that my bystarter is not closing off the circuit when it should. So...conflicting test results.

1/8" extension is about right.

Is this an aftermarket bystarter? If so, measure when cold from the bottom of bystarter body to top of the brass air valve tube.
It should be around 0.38 to 0.42 in. If the cold measurement is too short, the bystarter will never extend far enough to close the air valve.

If your carb is a Spree NQ50 or Elite E SB50, carb body damage can block the bystarter from extending. Inspect the carb body bore for the bystarter air valve. You would be looking for a bulge on the rear side - facing the carb mounting bolt.