How do i fix weak spark - Garden

Hi, I do a lot with these bikes, I think if you are getting a weak spark there is a couple things to check. First, do you understand how it builds the power to create the spark? The magnet in the flywheel has to be very close to the magnito or coil, if the gap is too much it will cause a weak spark, if the magnet is weak, weak spark, if the coil is shorting internally, weak spark. If the plug wire is damaged, weak spark. I hope this helps you.

Check your ignition coil. Could be the cause. Also check crank and camshaft sensors with a scope to see if you have a uniform pulses. I hope it helps.

pull flywheel and replace sheer key on flywheel to get spark on time

Sounds like stator pick up or stator its self is rusty causing a weak spark, (Just sand off) , or the coil is bad or spark plug wire is corroded

sounds like you have a stuck valve or out of adjustment

try cleaning the distributor cap and rotor arm and replace spark plugs and leads. hopefully this will fix the weak spark

check cable, spark plug, spark plug cap for good resistance levels. then check the coil. easy fix.

A weak spark can be attributed to a number of issue:
1. Wire from the magnetto to the spark plug is saturated with oil (clean well with degreaser)
2. Spark plug cap deteriorated. (most are not easily replaceable)
3. Spark plug fouled (insure you are using new)
4. Significant build up of rust on the flywheel (lightly sand rust off)
5. Bad Magnetto or CDI (especially if it has gotten wet or is cracked.) Note: (Cost typically prohibitive for replacement).
6. Spark plug gap significantly out of specs. (Regap to specs, retry)

If you are certain you have a weak spark, these are typical causes. Often, more likely problem is carburation, fuel filter and/or fuel lines - which are much easier and less expensive fixes! Hope for the fuel lines being cracked...Good luck :)

How do you know that the spark is weak?
Replace spark plug.
Check spark plug wire for leaks.
Replace fuel.
Clean points and reset.
If there is a battery check that it is at 12.5 during starting.

Check the cable, replace it with another cable to see if it is the wire or the distributor. If the spark is the same with the other cable it is the connection from the cap. I would remove the cap to see if anything is in it of it is corroded. While you have the cap off, look on the inside of it for erosion or corrosion.