Hello guys,
I am shifter kart racer with just one season of experience and I am still in the process of learning my YZ-125.
My YZ-125 is ported for short tracks and I have a Swedetech straight intake manifold. The reed cage is the stock YZ-125 year 2000 (four petals total) with Carbon Tech low tension reeds (142LT). The carb is a Keihin PWM with a pump around system. I've been told this is is the best intake combo.
For exhaust I have an RCE T3 pipe with an RVL titanium 12" silencer.
Spark plug is NGK BR10EIX
I race in Florida (at sea level pressure and like 90-100 F temp)
After my on-line research, I think I've got the proper method of reading spark plugs, by looking the ring that forms around the base of the insulator with an otoscope. So, I have started to lean down my engine up to a point were I run out of smaller main jets. I started from 165 and now I am at 150. However, the spark plug still looks wet and the dark ring at the insulator base is about 1~2mm tall.
Also, I have started to experience reeds problems. Last race I had reeds failure. The engine won't pull from the bottom range and when it hits 12,200 rpm it makes a cracking sound and acceleration is flatten out (usually It could go as high as 13,000 and still pulling). After inspection of the reeds I found that the corners were chipped to the point that I can see through to the other side of the reed cage.
Last Saturday (testing session) I replace the reeds for a new set of Carbon Tech low tension reeds (142LT) and chipped them again in just five laps.
Can somebody give me a clue of what is going on. I have a race next weekend and I am not certain if a new set of reeds will solve the problem. I am not sure if the reeds problem is related to the jetting, because it looks that the engine is still running rich.
Thank you!
I am shifter kart racer with just one season of experience and I am still in the process of learning my YZ-125.
My YZ-125 is ported for short tracks and I have a Swedetech straight intake manifold. The reed cage is the stock YZ-125 year 2000 (four petals total) with Carbon Tech low tension reeds (142LT). The carb is a Keihin PWM with a pump around system. I've been told this is is the best intake combo.
For exhaust I have an RCE T3 pipe with an RVL titanium 12" silencer.
Spark plug is NGK BR10EIX
I race in Florida (at sea level pressure and like 90-100 F temp)
After my on-line research, I think I've got the proper method of reading spark plugs, by looking the ring that forms around the base of the insulator with an otoscope. So, I have started to lean down my engine up to a point were I run out of smaller main jets. I started from 165 and now I am at 150. However, the spark plug still looks wet and the dark ring at the insulator base is about 1~2mm tall.
Also, I have started to experience reeds problems. Last race I had reeds failure. The engine won't pull from the bottom range and when it hits 12,200 rpm it makes a cracking sound and acceleration is flatten out (usually It could go as high as 13,000 and still pulling). After inspection of the reeds I found that the corners were chipped to the point that I can see through to the other side of the reed cage.
Last Saturday (testing session) I replace the reeds for a new set of Carbon Tech low tension reeds (142LT) and chipped them again in just five laps.
Can somebody give me a clue of what is going on. I have a race next weekend and I am not certain if a new set of reeds will solve the problem. I am not sure if the reeds problem is related to the jetting, because it looks that the engine is still running rich.
Thank you!
