Jos is looking for a mx bike
- Thread starter josmoloco
- Start date
If your bike is running good, and starting good you may want to just disregard the popping on decleration, or fix the exhaust airleak. If your bike starts easily, I have the HARDEST time imagining that it is LEAN on the pilot circuit. If you have an O2 sensor and gauge or access to one you will see what I mean. Backed off throttle and compression braking situations will have your engine running at it's richest, not leanest. In a closed throttle higher rpm situation you have lots of unburned fuel in your header. It can reach a temperature that it gets hot enough to partially ignite. Or you can get enough oxygen to light it when there is an air leak. Some people get so nervous about it, thinking their valves are burning that they richen up even more to stop it. You know how you can throw enough wood or paper on a fire to put it out? Anyway once done they swear up and down it was lean, and they richened it and "fixed it". Those same people can often be seen kicking and kicking and kicking when their overly rich bike won't start hot. A shorter silencer will make it do the same thing sometimes. Enough air can more easily get sucked back into the header to make it easier for the unburned gas to light off. Rich running engines still have combustion trying to take place as the exhaust gases exit, since it is slowing the burning process.
Anyway, that "story" along with a glowing header on idle are two of my favorite "it is idling lean" stories.
Kaw was still using the older design in 2007 looking at the notes I have. I had forgotten that the happy, arranged marriage went on the rocks in 06 though. Now that I look further Kawasaki had their own engine then, changed the crank in 2009, and that is the only one I worked on.
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If your bike is running good, and starting good you may want to just disregard the popping on decleration, or fix the exhaust airleak. If your bike starts easily, I have the HARDEST time imagining that it is LEAN on the pilot circuit. If you have an O2 sensor and gauge or access to one you will see what I mean. Backed off throttle and compression braking situations will have your engine running at it's richest, not leanest. In a closed throttle higher rpm situation you have lots of unburned fuel in your header. It can reach a temperature that it gets hot enough to partially ignite. Or you can get enough oxygen to light it when there is an air leak. Some people get so nervous about it, thinking their valves are burning that they richen up even more to stop it. You know how you can throw enough wood or paper on a fire to put it out? Anyway once done they swear up and down it was lean, and they richened it and "fixed it". Those same people can often be seen kicking and kicking and kicking when their overly rich bike won't start hot. A shorter silencer will make it do the same thing sometimes. Enough air can more easily get sucked back into the header to make it easier for the unburned gas to light off. Rich running engines still have combustion trying to take place as the exhaust gases exit, since it is slowing the burning process.
I thought it was a lean condition that crated the popping.... I may have it backwards as your detailed description makes food for thought.... been a while since I actually tuned bikes...
Anyway, that "story" along with a glowing header on idle are two of my favorite "it is idling lean" stories.
this is news to me, kawi got a nice ass yo