1100 acceleration stutter

[Eb90gsx]

Hi I just got a 90 gsx 1100 katana with 43000 miles and I am having an issue could someone please watch the following video and point me in the right direction

it doesn’t do it all the time but does most times and in the video I wasn’t really getting on it because of taking the video but on highway it is more of a long hesitation then multiple small ones bike falls on its face then picks up but still does over 150

https://youtu.be/cRjwds1fqTc

thanks, any help would be appreciated

[Eb90gsx]

Also it only does it below 3500-4000 rpm

[Kreylyn]

My first thought would carb related, and cleaning tuning for the pilot system and transition jets would be a good idea. Then a proper sync, and confirmation no vacuum or air leaks.

Second thought would be a spark break down due to lower voltage to the coils, hard plug wires or poor connections at the boots, and or bad plugs / arcing in general.

Is this an oem setup with stock air filter, air box, and exhaust? Jetkit installed? any other mods? How long has it sat?

Krey

[Eb90gsx]

Don’t think it’s vacuum leaks checked all over with propane while it was running never heard it speed up.
i don’t think it’s stock has k and n filter not sur if it has jet kits
Not sure if stock exhaust or a Canadian stock exhaust it has a Suzuki gsx exhaust but it’s 4 to 1 not 4 to 2.

iknow the previous owner and it Didn’t do it for him but it sat for 4 years since then.
when I got it I didn’t start it I drained carbs filled with sea foam let sit for a day then drained again
drained tank and ran half a can with 1 gallon of gas then filled up normally,.

[Eb90gsx]

Ordered carb rebuild kits got them in too carbs off and they are all filled with rust looks like I’m gonna have to seal the tank too

while I am at it I ordered new valvle cover gaskets too

[wfrpalm]

How did you fill the carbs with Sea Foam, I am thinking doing that also.

[Eb90gsx]

How did you fill the carbs with Sea Foam, I am thinking doing that also.

I drained the bowls then just dumped it in the gas lines till they were full

[wfrpalm]

Thanks, I'll give that a try.

[92xjunker]

Rust, is one issue. That K&N May be the other. Put the OEM type back in there and it could run better. High flow filters cause havoc with some CV carbs. Some bikes don’t seem to mind them, others don’t like them. Plus, you gain nothing from them.