Won't go above 3500RPM

[Guest]

So I just started another thread on this bike in rebuilds. I did a complete carb rebuild, I bought a new head and had a valve job done, readjusted the valves, synced the carb and put it back together. Now it revs until about 3500 then won't die, but it won't go past the 3500 mark. I don't really know where to put this on the forum, so I figured I start with the carb. I also suspect it could be a timing issue, or a result of a bad battery.

What should I do?

[Nessism]

Got the airbox installed?

Please check the Newbie Mistakes thread linked in my signature to see if anything strikes close to home.

[Triam]

Got the airbox installed?

Please check the Newbie Mistakes thread linked in my signature to see if anything strikes close to home.

Don't worry. I read it when I first joined. I went through it again and don't see anything.

I started it with the pods on (this may be a newbie mistake from the PO) and it started great, but it doesn't go past half throttle without shuddering.
I then took the pods off wondering if it was too ritch. It now takes a longer time to return to idle, but it runs great from half open and above. Jetting issue? If so, do I need to drop my needle or do I need to put in a smaller main jet?

[Nessism]

Don't worry. I read it when I first joined. I went through it again and don't see anything.

I started it with the pods on (this may be a newbie mistake from the PO) and it started great, but it doesn't go past half throttle without shuddering.
I then took the pods off wondering if it was too ritch. It now takes a longer time to return to idle, but it runs great from half open and above. Jetting issue? If so, do I need to drop my needle or do I need to put in a smaller main jet?

If the bike runs to high rpm's with no air filters that indicates someone messed with the jetting. Sorry, I'm not a jetting guy, so can't help you sort it out. I much prefer to keep my bikes stock so I don't have to monkey with such things.

[Triam]

Anyone else? I am thinking I'll take the top cover off my carb tomorrow and see if anything has been done to the needle to make it sit higher. Should I do that or should I just go to a smaller main jet?

[Triam]

my needle says 5gz6. Is that right?

[Triam]

also, there's a washer between my c-clip and the plastic part. Is that supposed to be there?

[tkent02]

You haven't answered the question, is the airbox installed?

[BassCliff]

Hi,

You'll find the stock specifications for most of the GS carbs in a chart on my little website. Compare those to what you have now. If the air intake system has been modified you will need bigger jets to compensate for the increase airflow. Do you also have a modified exhaust?


Thank you for your indulgence,

BassCliff

[Triam]

You haven't answered the question, is the airbox installed?

I did answer it. I don't have an airbox. I first ran it with pods, then started it without.

[Triam]

Hi,

You'll find the stock specifications for most of the GS carbs in a chart on my little website. Compare those to what you have now. If the air intake system has been modified you will need bigger jets to compensate for the increase airflow. Do you also have a modified exhaust?


Thank you for your indulgence,

BassCliff

Thanks. I'll get on that. I think I have a 130 main jet in, and you have listed a 115 stock. I do have both a modified intake and exhaust, but this makes sense because it runs very lean on the low end, but rich on the high end. That's probably the 130 jet screwing me up.

[tkent02]

I did answer it. I don't have an airbox. I first ran it with pods, then started it without.

No, actually you didn't until now. Which pods, real ones or the lousy screen sand sifters Emgo sells?

[Triam]

No, actually you didn't until now. Which pods, real ones or the lousy screen sand sifters Emgo sells?

I started it with the pods on (this may be a newbie mistake from the PO) and it started great, but it doesn't go past half throttle without shuddering.
I then took the pods off wondering if it was too rich. It now takes a longer time to return to idle, but it runs great from half open and above. Jetting issue? If so, do I need to drop my needle or do I need to put in a smaller main jet?

They're sand sifters. Not sure if they're from Emgo or not.

[tkent02]

Either find the original airbox, and put in all stock jets and have a perfectly running motorcycle or get some decent pods (K&N or APE) and start tuning the carburetors. It will take some trial and error to get it running perfectly, which few bother with. Most just get it so it fires on all four most of the time and haul ass.

Those crappy pods neither filter any dirt nor flow any air. Tuning is a nightmare, as the airflow is through them is all ****ed up.

[Triam]

Either find the original airbox, and put in all stock jets and have a perfectly running motorcycle or get some decent pods (K&N or APE) and start tuning the carburetors. It will take some trial and error to get it running perfectly, which few bother with. Most just get it so it fires on all four most of the time and haul ass.

Those crappy pods neither filter any dirt nor flow any air. Tuning is a nightmare, as the airflow is through them is all ****ed up.

The original box is a few previous owners back. I'd rather go the new pods route since it'd be almost the same amount of money. I've never heard of APE pods, but I'm new to this.

As for tuning, I want this bike to be a "one kick" bike, and to run wonderfully anywhere I take it. In the meantime I'll save my sheckles and get an K&N or other filter.