This one has me confused! She starts right up. She idles great. As soon as she hits 4000 starts to shutter and spit and sputter. If I'm on the throttle it will keep on going and calm down a little after 5000RPM. Most of my riding is around 35 -40 mph. Well that is right around 4000 RPM. Any thoughts guys?
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Shutters at 4000 RPM
- Thread starter MjrYam
- Start date
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- Tags
- electrical ignition
4,000 rpms is right in the mid range. Check your float height and main jet sizes as well as the condition of the diaphragms and emulsion tubes and the needle height if it is adjustable.
Does the bike feel like it is losing power during the shuttering at 4,000? If so you're likely too rich.
Any exhaust or intake mods? Any mods done to the carbs or jetting? How do the plugs look? Are your air filters restricted or dirty?
Does the bike feel like it is losing power during the shuttering at 4,000? If so you're likely too rich.
Any exhaust or intake mods? Any mods done to the carbs or jetting? How do the plugs look? Are your air filters restricted or dirty?
She is 100% stock original. No mods to exhaust or carbs. If I'm a betting man they may be the original plugs. The bike only has 10000 miles on it. I just changed out the original tires. I was thinking about getting new plugs and wires. I do need to get new air cleaners and I need to do an oil change. I took it on he highway last night. It seemed to run a little better after that. I was only on the highway for 5 or so minutes. Not a fan of cleveland highway riding!!!!
I would suggest replacing the plugs just because they are so cheap.
Focus on cleaning the air filters, intake, and the carbs. You need to open the carbs and inspect and clean them. If you're all stock there is no real reason to change any settings. At most you might want to richen the idle mixture as these bikes tend to be set fairly lean from the factory.
Definitely ride the bike more, but change the oil first. Just running it around a bit can prevent and even fix some issues. Sitting without running is not good for the bike.
Focus on cleaning the air filters, intake, and the carbs. You need to open the carbs and inspect and clean them. If you're all stock there is no real reason to change any settings. At most you might want to richen the idle mixture as these bikes tend to be set fairly lean from the factory.
Definitely ride the bike more, but change the oil first. Just running it around a bit can prevent and even fix some issues. Sitting without running is not good for the bike.
