Check Out My Squirt! (On my 04 KTM EXC 525 that is ;)

[GunnyB]

Hi All,

Based on a little research I'm of the opinion that the accelerator pump actuation should cause a fuel "squirt" out of the accelerator pump nozzle in the throat of the carby.

(keihin FCR 39)

My bike seems spray a "Mist" of fuel. It's more like a shot of aftershave than a squirt of fuel. I can't upload a video of this in action but I have put an image.

You can just notice the mist/cloud in the left image as compared to the right.

So, if it should be a "Squirt", I suspect there is a blockage in the passage to that nozzle and I'm sure you will tell me it will be easy to check and clean (Not) ?

Lastly, I'm also of the opinion that a couple of blips of the throttle (accelerator pump actuation) aids in starting a motorcycle to give it something to ignite. My bike is hard to start and I suspect it's trying to start dry because she's not a squirter. Is that logical or event such a thing?

Thoughts, comments and guesses welcome.

Thanks in advance

GunnyB 

[GunnyB]

I could not resist after my after shave comment. "Time to musk up"

 

[GunnyB]

"Stings the Nostrils" hahahahahaha

hahahahahahah!

[cobra46]

The squirt should be like a squirt gun.

The purpose of the squirt is to provide the engine with gas when the throttle is turned from low RPM when there isn't enough vacuum to pull from the jets.  The squirt should last long enough for the RPM to build up and start creating the normal intake vacuum.

My cold start routine that works every time is to pull the choke, twist the throttle twice to inject a bit of gas into the cylinder and then kick or press the button.

[KTMForecon]

There is a good post in here about the accelerator pump squirt and timing with video. As for clean I use some high pressure air and carb cleaner to blow out the circuit. Check the diaphragm for hole or small tear. Really shouldn’t be to hard to do.

[GunnyB]

17 hours ago, cobra46 said:

The squirt should be like a squirt gun.

The purpose of the squirt is to provide the engine with gas when the throttle is turned from low RPM when there isn't enough vacuum to pull from the jets.  The squirt should last long enough for the RPM to build up and start creating the normal intake vacuum.

My cold start routine that works every time is to pull the choke, twist the throttle twice to inject a bit of gas into the cylinder and then kick or press the button.

Thanks cobra46. I would very much like to adopt your start routine. ✔️

[GunnyB]

14 hours ago, KTMForecon said:

There is a good post in here about the accelerator pump squirt and timing with video. As for clean I use some high pressure air and carb cleaner to blow out the circuit. Check the diaphragm for hole or small tear. Really shouldn’t be to hard to do.

Thanks KTMForecon. I'll search for that video and do some more research on this part of the carby. 

[outofgas]

Make sure your valve are adjusted properly . this makes a big deffrence on the 04. I start mine cold with the two twist , push the button and kick at the same time. Mite take a  of kicks but it starts.

 

[GunnyB]

4 hours ago, outofgas said:

Make sure your valve are adjusted properly . this makes a big deffrence on the 04. I start mine cold with the two twist , push the button and kick at the same time. Mite take a  of kicks but it starts.

 

Thanks. I'm aware of the importance of regular valve maintenance on this bike. I did the valves not long ago and it make the bike a lot eaiser to kick. It's running quite well once it gets started but I should not have to kick it for 20mins. The E started is working fine. too. It's like it want's to start but there is just something not quite right for it to fire. I'm sure it's fuel/carby related. There is definitely no squirt on blip as #cobra46 described. I think in my case after a bunch of kicking and bliping at some point there is enough fuel/vapor for it to ignite. I decided to let my local KTM dealer take a look at it this time as I'm a bit busy with work to strip it down. I'll report back any findings.

[KTMForecon]

Be interesting to see what the dealer says is wrong. Sounds like a clogged pilot jet. Along with the accelerator pump squirt. There is also a screen where the float needle is that I've seen get clogged and cause the same problems with starting.  I'd be looking at cleaning or a rebuild kit  going through all the circuits  in the carburetor. 

Edited November 30, 2018 by KTMForecon

[GunnyB]

Hi, just an update on this thread.

The KTM dealer said it has a "weak" accelerator pump. I have ordered a new one and hope to install that soon. I'll report back the out come.

Thanks

 

[KTMForecon]

So what did you order? The spring? The rod? Diaphragm? Not a lot to the accelerator pump

[Burnrider]

ACCELERATOR PUMP    Yamaha –(5JG-14940-17) Honda-(16021-MEB-771)

2007 Honda CRF X 450 AP

Did a lot of the watch the squirt timing, but got better results with a the bike running & adjusting the screw with a short blip in 1st gear. whatevevva

Edited December 30, 2018 by Burnrider

[TM530]

Would be better to order the R & D bowl. Works heaps better than original and can be easily adjusted.