250r low end bog (vid)

[Fox250R]

https://youtu.be/9vIYCuuMyDw

Hi everyone!
So long story short I just rebuilt my R top end bottom end more aggressive port cool head replaced my 38 a/s with a 38pwk 180m 55 pilot klotz @ 50/1 190 psi. it runs ok but I’m getting this low end hesitation when I stab the throttle.

Any ideas what it might be? Thanks all…

[big specht]

You play with you needle at all? Or try a different plug I’ve had bad new plugs that caused running issues.

[Fox250R]

Checking that today actually. I hope it’s just the plug! Thank you

[yaegerb]

https://youtu.be/9vIYCuuMyDw

Hi everyone!
So long story short I just rebuilt my R top end bottom end more aggressive port cool head replaced my 38 a/s with a 38pwk 180m 55 pilot klotz @ 50/1 190 psi. it runs ok but I’m getting this low end hesitation when I stab the throttle.

Any ideas what it might be? Thanks all…

Wher is your needle? Sounds like an off idle bog. I would raise the need up a clip.

[Fox250R]

Wher is your needle? Sounds like an off idle bog. I would raise the need up a clip.

Never even looked tbh. Just ordered the PWK from Duncan. only thing I did was change the main from a 185 to a 180. I’ll take a look!
Thank you

[shortline10]

Agreed . A hesitation off idle I usually lower the clip which raises the needle , if it’s just slight go one notch , if it’s bad then go extreme and put the clip all the way down .
Also sometimes closing the spark plug gap to about 14 thousands helps with higher compression two stroke motors , I also try different spark plugs . Instead of the typical br8es try a NGK br9eg

[big specht]

Let us know what worked for you . It looks like we were all in agreement needle and/or plug

[Fox250R]

I will thank you. I’ll take it out this week and see what happens!
Thanks again

[Fox250R]

Hi all! So I dropped the main to 175 did a plug chop looks pretty good (light choc brown) Took it to the lake, still has a low end hesitation. Closed the gap on the plug just a bit to see if that might help (nope) played with my air screw 1 turn 1 1/2 and 2 turns also 2 1/2 (same) Air filter is clean. Same thing it was doing before when I stab the throttle it sputters for 1 second or so then it wakes up. Basically low end sucks atm. Going to check my cdi and then start with my needle and pilot. Other than that not sure what it Could be at this point. Fun times!


https://hosting.photobucket.com/images/s313/Fox250R/IMG_4812.JPG?width=450&height=278&crop=fill

https://hosting.photobucket.com/images/s313/Fox250R/IMG_4811.JPG?width=450&height=278&crop=fill

[shortline10]

Raise your needle by lowering the clip , that’s the adjustment for just off idle to about half throttle after that your on the main jet .

[dieseldigger]

Before you start digging into your ignition, you might want to try putting the airbox back in and/or try a smaller carb. I know that's not what you want to hear. You've gone up 6mm in carb size and put on a VERY unrestrictive air intake system. Your intake velocity has been drastically decreased. Porting and a pipe help with flow, but it may not be enough. Too large of carbs are notoriously difficult to jet. You definitely need a richer low speed circuit. Slide, needle and needle jet? Possibly the pilot as well.
Just food for thought before you spend money on ignition.

[Fox250R]

Thank you Going to try the carb first.

[Fox250R]

Raise your needle by lowering the clip , that’s the adjustment for just off idle to about half throttle after that your on the main jet .

I will try that thank you!

[Fox250R]

So after looking at my plug again it seems a bit rich on the top end. So went to a 170 main and pilot from 55 to a 50. Rode it around a bit and seems very snappy but won’t really know until I get to back down to the beach. We will see!

[Fox250R]

Had a Chance to ride it after the carb changes and basically mid and top is explosive but the low end still has a hesitation or something going on. Going to try a dgh needle and see if that changes anything.

[Fox250R]

Soooo my PWK has DGH already in it i changed the clip from 3rd to 4th and switched out the slide from 6 to 7. Still has the low-end bog or stutter. Not sure what to do now...