Suddenly Stopped Working!

[Quentin's]

Greetings,

I am new to the world of motorized bikes and recently got myself one. It had been running "smoothly" until a few days later when I encountered an unexpected issue. I started the bike, let it idle for a while, and then decided to take it out. Unfortunately, things didn't go well.
As I rode, I noticed that it suddenly stopped working and eventually came to a complete stop. The engine seems to have failed, and it won't start or idle either. Then I tried starting it again, but it wouldn't budge.

What might have gone wrong?

Has anyone experienced anything similar? I want to hit the roads again as soon as possible! Thanks for your help!

 

[Sidewinder Jerry]

When seeking advise from us; a good place to start is by saying what kind of engine you have. Posting pictures/videos helps even more.

 

[Quentin's]

When seeking advise from us; a good place to start is by saying what kind of engine you have. Posting pictures/videos helps even more.

2-Stroke 100CC

 

[Venice Motor Bikes]

My first questions are pretty standard... does it have spark, compression & does it have gas in the tank?
& if so?, how did you do the spark & compression tests?

This is another thing that happens randomly to these 2-strokes... Take off the float bowl from the carb & see if the jet fell out & is laying down in the bowl.

 

[Quentin's]

My first questions are pretty standard... does it have spark, compression & does it have gas in the tank?
& if so?, how did you do the spark & compression tests?

This is another thing that happens randomly to these 2-strokes... Take off the float bowl from the carb & see if the jet fell out & is laying down in the bowl.

To be honest, all I know is that the bike passed the standard checks before its first ride: it had sufficient compression, generated spark, and contained fresh gas inside the tank, which means there is still fresh fuel in the motor.

However, now I noticed: regardless of how hard I used to crank, these days it rarely spins. Only occasionally, on alternating attempts, does it rotate briefly. Why does the engine sometimes react to kicking and other times remain unresponsive now?
This resistance and lack of response concern me.

 

[Venice Motor Bikes]

To be honest, all I know is that the bike passed the standard checks before its first ride: it had sufficient compression, generated spark, and contained fresh gas inside the tank, which means there is still fresh fuel in the motor.

However, now I noticed: regardless of how hard I used to crank, these days it rarely spins. Only occasionally, on alternating attempts, does it rotate briefly. Why does the engine sometimes react to kicking and other times remain unresponsive now?
This resistance and lack of response concern me.

How much oil did you mix into the gas?

 

[Quentin's]

How much oil did you mix into the gas?

It is an approximate ratio of 30:1.

 

[Venice Motor Bikes]

It is an approximate ratio of 30:1.

Well... until you post the results (& methods) of the spark & compression tests; there isn't much more I can help you with

 

[wrench]

However, now I noticed: regardless of how hard I used to crank, these days it rarely spins. Only occasionally, on alternating attempts, does it rotate briefly. Why does the engine sometimes react to kicking and other times remain unresponsive now?
This resistance and lack of response concern me.

Bevel gear could be defective and the gear teeth have ground off

 

[Quentin's]

Well... until you post the results (& methods) of the spark & compression tests; there isn't much more I can help you with

What issues could have arisen with the ignition parts that I should be careful of?

 

[Quentin's]

Bevel gear could be defective and the gear teeth have ground off

It indeed has no such damage or wear.

 

[Quentin's]

I have a picture of the part that may have been affected by the ignition. Showing some red spots near the cable connection. Do you think this could be the cause of the issue?

 

[Quentin's]

ASAP?

 

[Venice Motor Bikes]

As I mentioned before... We need to know how did you got the results of your spark & compression tests?? (because many new builders think they have spark when they really dont)

To test for spark; you remove the spark plug & re-attach the wire to it; then touch the threads of the plug to the metal of the engine (so it has a good electrical ground), Then have someone spin the rear wheel so the engine turns fast... (you should be able to see the spark jumping the gap in the plug)!! If you don't see a spark?, thats your problem.

Next... while the plug is out, use a compression tester in the empty spark plug hole (while spinning the rear wheel) to test for compression

And as mentioned before... remove to float bowl from the bottom of the carb & see if the brass jet is sitting at the bottom of the bowl... (sometimes that happens).

Let me know the results of these tests.

Also... the timing is fine as long as you didn't touch it... but if you did?, simply put it back on with the key slot in the 1 o'clock position. (don't forget to install the woodruff key)

 

[Quentin's]

As I mentioned before... We need to know how did you got the results of your spark & compression tests?? (because many new builders think they have spark when they really dont) remove to float bowl from the bottom of the carb & see if the brass jet is sitting at the bottom of the bowl... (sometimes that happens).

Let me know the results of these tests.

View attachment 115297

Let me make one thing clear: It's also worth it: the carb is not even responsible for the engine not starting. The spark and compression values also proved to be sufficient. Consequently, the search for the cause of the problem must shift to other components and processes outside the carburetor area. I took out the magneto to check if the contact breaker was damaged. Noticing that it was in perfect shape, I put it back in its original position without touching the timing. Previously, the bike ran and suddenly switched off without any active interaction.

 

[Venice Motor Bikes]

Let me make one thing clear: It's also worth it: the carb is not even responsible for the engine not starting. The spark and compression values also proved to be sufficient. Consequently, the search for the cause of the problem must shift to other components and processes outside the carburetor area.

Look bro... I've been doing this for a long time... I'm doing my best to help you. (because you obviously need someone's help with your bike). If you can't work with me here?, there isn't much more I can do. (maybe one of the other guys here will stop talking about hearing aids & arthritis & help you too... (but that's not likely)

 

[Quentin's]

Look bro... I've been doing this for a long time... I'm doing my best to help you. (because you obviously need someone's help with your bike). If you can't work with me here?, there isn't much more I can do. (maybe one of the other guys here will stop talking about hearing aids & arthritis & help you too... (but that's not likely)

Listen, I do fully appreciate your help and vast experience. From what you're knowing now about my situation, the bike has proper spark, it does ignite the fuel, receives fresh gas, and maintains high compression. Yet, it still refuses to start, and strangely enough, it switched off without any noticeable trigger during the last ride. All I want is to immediately identify the bike problem and get a rapid fix suggested for this perplexing situation.

 

[Venice Motor Bikes]

Listen, I do fully appreciate your help and vast experience. From what you're knowing now about my situation, the bike has proper spark, it does ignite the fuel, receives fresh gas, and maintains high compression. Yet, it still refuses to start, and strangely enough, it switched off without any noticeable trigger during the last ride. All I want is to immediately identify the bike problem and get a rapid fix suggested for this perplexing situation.

Did you open up (& inspect) the carb like I suggested?

 

[Sidewinder Jerry]

Let's start with the most basic of basics. Are you using a 100% ethanol free gas. Compression valves??? I've never heard of a 2 stroke having valves.

 

[Tom from Rubicon]

"(maybe one of the other guys here will stop talking about hearing aids & arthritis & help you too... (but that's not likely)"
Jeez Norm, was it getting that bad?

Air, fuel, and spark= run. Any one of the three will have you walking. The conductors in #12 look fine.
Test for continuity. Faulty kill switch? Carb not delivering fuel?
A neighbors bike took a carp. Told him to get a new CDI. Runs like a champ now. I don't power with two stinks. but the forums are full failed CDI's. But carp in a carb. jet comes in second.

Tom