Bike won't go past 4400 rpm

[blmiller8]

I can't figure out why my bike won't go past 4400rpm in any gear. I think my problem might be that I am running pod filters and the hose the is coming from the head to the stock airbox is diconnected. I also thought it might be a jetting problem. But the bike feels like it just won't go past 4400 almost like it runs out of gas. If anyone has any ideas please tell me.

[mcneilk]

i'm not the best at answers but i'll let you know a bit about the question. what is the bike? did it run good before? if so what did you change?

my guess is that if it feels like you are running out of gas then you might be. probably to lean with the pods. change the main jets and the clips/shims on the throttle needle. could be fuel petcock as well. switch it to prime and see if that makes a difference. i don't think the crankcase breatherhose will make much difference unless the hose is plugged.

[doctorgonzo]

Make sure there are no bends or crimps in your fuel line, are you running any type of inline fuel filter, if so what kind, gunked up filter on the petcock maye... The symptoms are fuel starvation. I had it happen once when my fuel line got crimped. It flows enough fuel to handle low rpm fine, but when you open it up the compromised fuel line can't flow enough gas.

[Don-lo]

Yup, jetting may need to be bumped up, could be fuel delivery problems (kinked hose, bad petcock, plugged filter), or could also be a bad diaphram (won't lift with vacuum). These would be the first places to check.

[Dave8338]

TOO LEAN...

Pods, as mentioned, will lean out the fuel mixture to the point where you simply don't have enough fule in the mixture to spin the engine any faster. Do you have a header on the bike? If so...that just makes things worse. If you want to set things up without a kit, you'll be spending time on plug chops. If not, you might rather buy a jet kit (stage 1 should work with just pods alone) or maybe a stage 2 if you have a header.

Also as mentioned you can raise the clips on the needled but that will only help in the bottom end and up to the midrange (about 4500). After that, you're going to need to bump the mains up a bit...

[ThAzKat]

so many different things
1. fuel delivery
2. jetting
3. proper output from reg/rec
4. float setting
5. petcock clean?
6. foreign material in tank clogging petcock
7. coils-I had this problem with a cb I had, would run great up to about 4500 rpm, did a resistance test on coils, they were bad
8. all the above?

without knowing what you have done and haven't or knowing carb, tank, petcock condition it is tough to answer.

[blowerbike]

GS CV carbs will pull to about 4k give or take when the air box is removed and ((((NO)))) jet kit is installed.

[doctorgonzo]

GS CV carbs will pull to about 4k give or take when the air box is removed and ((((NO)))) jet kit is installed.

Yeah, I tend to think it's not jetting. The jetting may well be wrong, but don't think it would cause it basically stop running when it hit the main jet. More likely a spark or fuel flow problem.

[Dave8338]

Shall we takes some bets?

First I need a total list of the mods, then we gamble!

[anthonygs1000]

I think all pod filters should come with a WARNING can not be used alone must have carbs reJetted to make bike run right. I have seen it a bunch of times "the bike ran great I spent $160.00 on these K&Ns and it wont get out of its own weight I dont understand" you add way more air now it needs way more fule. My bets on the jets

[blowerbike]

follow me on this...
stock carbs/main jets/remove air box/engine will signal off when it hits the stock main jet and goes lean.
fact!
and just replacing with bigger mains wont make the transition any smoother, it will just pull higher revs than with stock mains...
its like flipping a switch folks..
when it stops pulling roll back the throttle a little bit and it will start pulling again.

[Dave8338]

follow me on this...
stock carbs/main jets/remove air box/engine will signal off when it hits the stock main jet and goes lean.
fact!
and just replacing with bigger mains wont make the transition any smoother, it will just pull higher revs than with stock mains...
its like flipping a switch folks..
when it stops pulling roll back the throttle a little bit and it will start pulling again.

Also as mentioned you can raise the clips on the needled but that will only help in the bottom end and up to the midrange (about 4500). After that, you're going to need to bump the mains up a bit...

Hmmmmmm...sounds familiar.

[blmiller8]

Here is a list of mods. I know its bored when I bought it I cant remember the bore but other than that the bike was stock. The airbox boots were bad so I took it off and my girlfriend threw it away when she was cleaning my shop. He also told me he had allready rejetted for the bore. But I have put a 4-1 exhaust.

Mods:
4-1 Exhaust
Pod Filters
Bigger Bore with Stage 1 kit from what the seller said

The shop I took it to said it was just the stock filter not being on there which I have a hard time believing its just that. They did take my carbs apart and clean them for me. It runs a little better but still bogs at around 4800-5000 and cant get past like 50mph. Im thinking I might need to just go ahead and get the stage 3 kit. Dynojet has one for a Katana 550. Does this kit require me to do any fabrication to make it work on my bike.

Does that hose coming of the top of the valve cover need to go somewhere. Or can I just put a small filter on there.

I understand the needing of more fuel with more air. I am a helicopter mechnic but these carbs are kickin my ass.

Start the bets Dave8338

[doctorgonzo]

Here is a list of mods. I know its bored when I bought it I cant remember the bore but other than that the bike was stock. The airbox boots were bad so I took it off and my girlfriend threw it away when she was cleaning my shop. He also told me he had allready rejetted for the bore. But I have put a 4-1 exhaust and Im getting cone filter in the mail soon.

Mods:
4-1 Exhaust
No Airbox just some simulated filters cut t-shirt with a clamp
Bigger Bore with Stage 1 kit from what the seller said

The shop I took it to said it was just the filters not being on there which I have a hard time believing its just that. They did take my carbs apart and clean them for me. Does that hose coming of the top of the valve cover need to go somewhere.

Well looks like the guys voting for jetting were right. The shop is correct, no air filters in place makes it run so lean it croaks out. With no air filters of any kind and a stage 3 kit you'd just be kinda lean, with a stage 1 kit you are so lean it won't run. If you're going to install pods, go ahead and buy a dynojet stage 3 kit, around 120 bucks. You could try and jet it yourself, but unless 120 dollars is worth more to you than the hair you'll pull out, just cough up the money.

That hose is the breather. It stops pressure from building up inside the engine. Buy a $6 breather filter from autozone and enough hose to route it to the back of the bike somewhere.

[blmiller8]

Ok I have no problem spending money on jetting the bike I just wanted to make sure I was going the correct route. Thanks for the help I will let y'all know what happens. Recip engines that are carburated can be tricky if you aren't familiar with them I am so used to turbines. Sorry I don't mean to sound like a retard to y'all.