Sputtering and lagging between 3000 and 4000 RPM

[brianinpa]

Today I was able to get out for a decent ride on the 1200 and I started to see that between 3000 and 4000 rpm in 5th gear, the motor is sputtering and starts to fall on itself. It seems like every other gear there is no problem: accelerated right through. In 4th, when tickling the red line... oh boy - that was fun! As soon as I shift into 5th, it starts to fall over. Eventually I realized that even in 4th gear it was sputtering too, just not as bad.

I have had problems with these carbs in the past, (https://www.classicgoldwings.com/forum/viewtopic.php?f=24&t=7192) so I am thinking I may need to open all 4 of them up and take a look. I just want to see if there is one specific thing I should look for or am I looking in the wrong direction.

 

[joedrum]

keep the gas off on this when sitting its liable to load a cylinder up with gas

 

[brianinpa]

joedrum » Sun Feb 23, 2014 8:21 pm[/url]":19lr9yem]
keep the gas off on this when sitting its liable to load a cylinder up with gas

Way ahead of you Joe. I never had that happen before and I didn't want to take a chance now either.

 

[slabghost]

Sounds like the slides aren't lifting right.

 

[dan filipi]

Just a clue what you might go after...
Mine was doing that once and turned out it was one carb flooding over making that cylinder run real rich.
Was worst under load.

 

[backyardtrouble]

Hmmm.....i think i would make sure that the sync is correct, if it is, then i would be thinking of pulling the carbs and checking the vaccum diaghrams, these often tend to dry rot and get small pin holes in them. If you take the carb apart, take the diaghrams and look closely at them looking at a light behind them. You may see some holes or deteration. Also check the floats, correct adjustment. And while your in there, check the jets. Stalling is a lack of fuel source when you need it, so i would assume it will be carb related, since it is running good before you get to these 4th and 5th gear.

 

[charles franz]

Brian, If it started at the high end and started to do it in the the next lower gear, I would check the fuel filter and progress to the the pump pressure, If it runs thru the lower gears fine and starts on the high end, Try choking it a little and see if it helps, Hope this helps, Thanks Charlie in NC

 

[dan filipi]

charles franz » Sun Feb 23, 2014 7:35 pm[/url]":2aovx0ga]
Brian, If it started at the high end and started to do it in the the next lower gear, I would check the fuel filter and progress to the the pump pressure, If it runs thru the lower gears fine and starts on the high end, Try choking it a little and see if it helps, Hope this helps, Thanks Charlie in NC

Very good suggestion.
Good process to help narrow down the culprit.

 

[brianinpa]

dan filipi » Sun Feb 23, 2014 10:48 pm[/url]":3flc1kar]

charles franz » Sun Feb 23, 2014 7:35 pm[/url]":3flc1kar]
Brian, If it started at the high end and started to do it in the the next lower gear, I would check the fuel filter and progress to the the pump pressure, If it runs thru the lower gears fine and starts on the high end, Try choking it a little and see if it helps, Hope this helps, Thanks Charlie in NC

Very good suggestion.
Good process to help narrow down the culprit.

Yup, that right there is some good stuff!