Bike won't stay running

BikerZack941

New Member
I am having a issue with my bike. It was running fine then started to lose power and now I do not have any power behind the engine. The motor is turning over but won't stay running. I have spark, compression and fuel. I am at a loss as to what the issue may be. I have cleaned the carb, tightened all bolts, nuts and screws, disconnected the Killswitch. I have also changed spark plug from the original to an ngk plug. The engine is pretty new I think right at three weeks old. It has been my daily driver. The kit is an Amazon bbr tuning engine.
 
Hello BikerZ and welcome to the forum!
bbr tuning - Good Stuff! Curious to know your fuel mix. Before starting a new / re-build engine, I always squirt the top end with straight oil through the plug hole and roll the bike around with the plug out giving it an initial lubrication. I treat a new engine as if the insides are dry only because we don't know how long they sat on a shelf in a warehouse before we get them. I use basic 2 stroke oil mixed 32:1= 4oz oil 1 gal gas from the start, which I know contradicts the rules of break in, yet never had a problem after many new engines and rebuilds - doing a pre-lube with straight oil in the cylinder first. Plug gap should be .23 - .25. a gradual power loss hmmm? I can think of a couple reasons for this. Electrics, only 3 things--- you already put in a good quality plug so that takes care of the first concern. 2. Check wires @ the Horse Shoe (pick up coil) that surrounds the spinning magnet my experience is when this goes bad it happens instantly and creates a no spark no start situation which doesn't sound like your prob. Now the mysterious black box (CDI) which creates the spark can weaken and burn-up over a short period of time. If defective this IS a gradual occurrence in my experience. Certainly will cause you to pull your hair out but rears it's ugly head only after engine has come up to temp and gets worse the longer you ride before a cool down. Compression issue/concerns? check crank seals - pull left side mag cover (4 screws) and look for oil seepage behind the spinning magnet. If clean go to the other side then pull Clutch cover (5 screws) and look for oil or fuel behind the small gear. If all that looks good. Check for leaks @ the base of cylinder and around the two halves of the block itself.
With all that said there is one more thing left to check and I hope you need not go there yet so to wave off bad JuJu i will not discuss that as of now. My experiences may not be exactly as others so it's good to have others chime in. Do all of the above, watch your post often, then get back to us.
With all the knowledgeable Good people here we'll figure it out together. Good Luck!
Also curious of your elevation / where you are @ close to sea level?
 
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Hello BikerZ and welcome to the forum!
bbr tuning - Good Stuff! Curious to know your fuel mix. Before starting a new / re-build engine, I always squirt the top end with straight oil through the plug hole and roll the bike around with the plug out giving it an initial lubrication. I treat a new engine as if the insides are dry only because we don't know how long they sat on a shelf in a warehouse before we get them. I use basic 2 stroke oil mixed 32:1= 4oz oil 1 gal gas from the start, which I know contradicts the rules of break in, yet never had a problem after many new engines and rebuilds - doing a pre-lube with straight oil in the cylinder first. Plug gap should be .23 - .25. a gradual power loss hmmm? I can think of a couple reasons for this. Electrics, only 3 things--- you already put in a good quality plug so that takes care of the first concern. 2. Check wires @ the Horse Shoe (pick up coil) that surrounds the spinning magnet my experience is when this goes bad it happens instantly and creates a no spark no start situation which doesn't sound like your prob. Now the mysterious black box (CDI) which creates the spark can weaken and burn-up over a short period of time. If defective this IS a gradual occurrence in my experience. Certainly will cause you to pull your hair out but rears it's ugly head only after engine has come up to temp and gets worse the longer you ride before a cool down. Compression issue/concerns? check crank seals - pull left side mag cover (4 screws) and look for oil seepage behind the spinning magnet. If clean go to the other side then pull Clutch cover (5 screws) and look for oil or fuel behind the small gear. If all that looks good. Check for leaks @ the base of cylinder and around the two halves of the block itself.
With all that said there is one more thing left to check and I hope you need not go there yet so to wave off bad JuJu i will not discuss that as of now. My experiences may not be exactly as others so it's good to have others chime in. Do all of the above, watch your post often, then get back to us.
With all the knowledgeable Good people here we'll figure it out together. Good Luck!
Also curious of your elevation / where you are @ close to sea level?
Well it turns out that I must have gotten something pulled in to the head because it was toast the piston looks like it go into a fight with a blender on one side so I have to rebuild the top end. New piston, rings, cylinder the works.
 
WOW! that sucks. Exactly what I didn't want to talk about in my welcome post.
Be sure to flush the motor of any broken pieces before the new top end is installed.
The smallest piece of metal left inside could easily be sucked in to the cylinder and destroy it again. Before starting for the first time, do the oil pre-lube mentioned above.
During the autopsy you should determine cause. Broken Ring? Retaing clip? Blown out wrist pin bearing? -----Sorry you had a bad beginning.
 
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