Cleaning carbs

Tomorrows job is cleaning out the carbs of the shit that got in from the tank (it was full of rust but it was the only tank we had) along with any scum from the old fuel. The engine starts and idles well, but once it get's over about 4-5K it bogs down and stutters and tried to die.

Since it appears to be little more than a blocked main jet I was wondering if it's possible to simply open the throttle all the way and spray carb cleaner into the jet to clean it out? Or am I going to have to disassemble the engine carb to clean out the main jets? Either way isn't a huge problem but I just wanna know if I can just spray directly into the jet? I'm thinking I can't but wasn't sure.

Pull the carbs off, open the bowls and assess the condition.
Steve
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882

I suggest you install an inline fuel filter after cleaning the carbs. Otherwise they may quickly become contaminated again. Ed

Your pilot jets are a LOT smaller than the mains and 9/10 plug up first (unless you have a thick layer of crud in the bottom of the bowls) you can drain the carbs individually (each has a drain plug) and see if they have crud come out.

It is always a good idea to pull the carbs on any new to you bike, But, stuttering and bogging out at 4-5k sounds like it may be too cold to be revving the crap out of (is it riding or just sitting on the stand) valves out of adjustment (check valves first ALWAYS) or possibly you are trying to run it without the air box, or with crappy rotted out intake boots?

floivanus wrote: Your pilot jets are a LOT smaller than the mains and 9/10 plug up first (unless you have a thick layer of crud in the bottom of the bowls) you can drain the carbs individually (each has a drain plug) and see if they have crud come out.

It is always a good idea to pull the carbs on any new to you bike, But, stuttering and bogging out at 4-5k sounds like it may be too cold to be revving the crap out of (is it riding or just sitting on the stand) valves out of adjustment (check valves first ALWAYS) or possibly you are trying to run it without the air box, or with crappy rotted out intake boots?

Already checked all the valve clearances and they're all perfect (only 8k old), thankfully all the intake boots are fine (well, they pass a basic spray can test, I'll have a closer look later), but the carbs definitely need cleaning, the bike had none of these poping or bogging issues till we tried feeding it from the fuel tank, only then did it do this, we found out why when we drained the tank and a load of sludge and rust came out with the fuel. (thankfully a vinegar treatment worked perfectly and the tank is not spotlessly clean inside)

I've decided I'll just take a few days cleaning the entire thing, will do some good cleaning the entire thing and not just a quick spray down, and I need to do other stuff on the bike anyway.

Make sure you clean the fuel tank and petcock and install filters or cleaning carbs will become a weekly pastime.

You can get these at any dirt bike motorcycle shop.
Steve

Note the metallic filter element.

As carb-fitted motorcycles are gravity fed (gasoline flow from the fuel tank is dependent on the force of gravity alone -- not a fuel-pump), Inline filters with a paper element are likely to allow insufficient fuel flow through the filter and result in fuel starvation.

Good Fortune!

Patton wrote:

Note the metallic filter element.

As carb-fitted motorcycles are gravity fed (gasoline flow from the fuel tank is dependent on the force of gravity alone -- not a fuel-pump), Inline filters with a paper element are likely to allow insufficient fuel flow through the filter and result in fuel starvation.

Good Fortune!

Yeah don't worry guys I'm not a total fool, I've been cleaning out the tank for days on end and am going to use a fuel filter, that's more than obvious, thanks for the help though. Turns out my carbs looked like they had been on the Titanic, they where full of rust and green death, still ran but I'm kind of amazed they did at all, but now they're clean inside and relatively clean outside. Considering getting an entire rebuild kit, some of these seals are more than questionable after sitting for over 2 decades

When it comes to fuel filters, fuel lines, and fuel line clamps for the KZ I've tried a few and here's what works best for me (see link). Ed

www.kzrider.com/forum/3-carburetor/59932...the-fuel-line#685995

650ed wrote: When it comes to fuel filters, fuel lines, and fuel line clamps for the KZ I've tried a few and here's what works best for me (see link). Ed

www.kzrider.com/forum/3-carburetor/59932...the-fuel-line#685995

Nice solution Ed, this is nearly identical to what I did on mine as well, using the Pro Motion tygon line and a brass 90 elbow to solve a partial kink. Thanks for sharing for those not aware of it

Brett

Irish-Kawi wrote:

650ed wrote: When it comes to fuel filters, fuel lines, and fuel line clamps for the KZ I've tried a few and here's what works best for me (see link). Ed

www.kzrider.com/forum/3-carburetor/59932...the-fuel-line#685995

Nice solution Ed, this is nearly identical to what I did on mine as well, using the Pro Motion tycoon line and a brass 90 elbow to solve a partial kink. Thanks for sharing for those not aware of it

Brett

Once the bike is all said and done I'll probably have a look into doing this, but for testing purposes some cheap line and a crappy filter will have to do, not as if we're gonna be spanking it around for a while yet. The entire bike is gonna be stripped, powder coated, cleaned and all sorts of lovely things between now and then. Haven't had any issues with that kinking, maybe it's not always an issue, or only happens with specific fuel taps, but now I know how to fix it if or when it happens.