Lacking power(Surging)

[Hughes8524]

I have a 04 Katana that i bought just over a week ago.. it had been running decent.. But yesterday I got on it to ride over to a buddys garage to clean out my carbs and when I got on the Highway I got up to about 70 and it wouldnt really want to go faster... I literally had the throttle turned all the way and was not picking up speed... There was a couple times where it began to get that power and sort of surge and pick up speed but then shortly after it seemed like it had no more power to give again... After I cleaned the carbs I was hoping that would fix this problem but it did the same thing on the way home.... I also replaced all of the spark plugs... Any help is very much appreciated. Im sure I didnt explain this that well so if anyone has questions feel free to ask and ill try to explain better.. I just want to ride lol.

[Kreylyn]

I have a 04 Katana that i bought just over a week ago.. it had been running decent.. But yesterday I got on it to ride over to a buddys garage to clean out my carbs and when I got on the Highway I got up to about 70 and it wouldnt really want to go faster... I literally had the throttle turned all the way and was not picking up speed... There was a couple times where it began to get that power and sort of surge and pick up speed but then shortly after it seemed like it had no more power to give again... After I cleaned the carbs I was hoping that would fix this problem but it did the same thing on the way home.... I also replaced all of the spark plugs... Any help is very much appreciated. Im sure I didnt explain this that well so if anyone has questions feel free to ask and ill try to explain better.. I just want to ride lol.

Does it have a K&N air filter?

Krey

[Hughes8524]

When I cleaned the carbs I took the Air Filter out it looked almost brand new... But its not a K&N

[Kreylyn]

Check your fuel flow, fuel filter is correct and flowing right, and no kinked fuel lines.

Krey

[Hughes8524]

Ill check that after I get home from work, any other possibilities because it was running fine until i jumped on it yesterday and I hadnt messed with anything.

[shift6]

check ur fuel tank to see if you have any rust / crap in the bottom. What could of happened is when you got on it you injested what ever crap was in the bottom of the tank into your carbs.

Now how did you clean your carbs, i have the suspicion that you did not properly clean them. You need to have completely disassembled the carbs, soaked everything in carb cleaner for a good 12 - 24 hours, blew all the jets out with compressed air, and then reassembled and synced the carbs.

[shpielers]

Sounds like your buddy helped you clean those carbs in a single day - hate to say it but that means they're not clean. Take a gander at carbs 102 for a how to. It might be you just loosened up something that's now clogging you up.
But definitely look into what Krey suggested too.



Misread that the first time - it started acting funny on the way to your friends place, not afterwards. Still, those carbs aren't clean. While you're looking into fuel delivery, check your petcock is functioning properly/flowing well.

[Hughes8524]

Once we got into them there wasnt really much built up in any of the bowls or jets but soaked them for a couple hours and then blew them all out... There was little gunk at all in any of the parts... Ill check the petcock also... If it was the fuel filter would it start acting up just over night like that? I just dont understand how it was running fine the night before then all of a sudden the next morning I have this problem.

[Kreylyn]

Once we got into them there wasnt really much built up in any of the bowls or jets but soaked them for a couple hours and then blew them all out... There was little gunk at all in any of the parts... Ill check the petcock also... If it was the fuel filter would it start acting up just over night like that? I just dont understand how it was running fine the night before then all of a sudden the next morning I have this problem.

Just one possible reason...

Your carbs must maintain a specfic level of fuel in the bowls for the carbs to mix the air flow through them with fuel in the correct mixture.

If the fuel flow to the carbs starts to slow down for any reason, you will not see a problem until it reaches the point where use over comes flow. Higher rpms for long periods of time (and that comes with higher speeds ussually)... is where this is going to become most evident.

So the bike very well may run fine for lower rpms, and even short stints at higher rpms as it uses the fuel in the bowls. Here's a tip for ya... I can turn the fuel off on your bike, and stop flow completely... it will still run for 3-8 mins. That's because it's using the fuel in the bowls, it's just not being refilled.

If it's just on the pivot point of fuel use vs fuel replacemnt, then you will see it only acting up some times... and fill the bowls again.

Thus... check the fuel lines, filter, so on... those are the most common reasons for decreased fuel flow.

And make sure the fuel lines are re-enforced lines... not vacuum lines. Vacuum lines will collapse with heat and cause slower fuel flow too.

Krey