Alright, so my jetting is pretty close to spot on for most of my riding (recipe in my sig line), I occasionally have a light miss around 5K but not so often that I am motivated enough to look for the issue.

The weather has cooled off enough to spend some time playing in the woods, and as I get faster and more experienced, I'm catching more air than I used to.

Yesterday I hit a few terraces more aggressively than usual and spent more time with one or both wheels in the air... big fun, but a couple of times the engine bogged down afterwards a hundred or so yards down the trail. It usually cleared it's throat within a few seconds, but felt like it might stall as if I was running out of gas.

I figured I might have stirred up some trash in the float bowl but wanted to get an opinion from the more experienced before spending the time pulling the carb. Other than bogging after small jumps, she ran like I beast (at least as much a beast as an CV carbed 250 can be expected to be....lol)



Anything in particular I should look for.

 

Yep, intermittent fuel starvation that lasts long enough to cause a temporary running issue.. Since you provided a succinct description of the exact environment before and during the issue, I would guess the gas left in the bowl gets you "a hundred or so yards down the trail" , and that the problem lies with a failure to replenish the bowl (even though the gas tank has plenty of fuel ?)... So,,,, petcock system, all fuel filters and in tank screens, needle/seat/float assembly, Hose routing for all tank and carb venting.. etc

 

Thanks for the input Klxster, I read a few threads around the web that mentioned fuel level being too low can cause a similar issue, and I don't believe I have ever checked it. I'll plan on taking a look at it next weekend, and worst case I'll pull it apart, clean the bowl, and reset the float height.

On an unrelated note... I kept my Christmas spending under control and barring any odd tax surprises in the next couple months, I'll be doing some serious big bore research/shopping sometime soon. I'm not so sure I'm ready to trust the economy class Chinesium 300 kit, but BB's 351 or maybe even KK's 330 kit are sounding pretty sweet right now. I'm also due to replace all the fuel and water hoses on both my '09 KLX and '08 Versys. It makes me sad that the 3 stock fuel lines for the KLX run over $60 for the set....

 

Use the quick and dirty clear tube method - clear tube hooked up to the bowl drain and held up alongside the bowl, open the drain and check the fuel level in the clear tube against the "bowl to carb body" mating surface.. Fuel level needs to be .5 mm above the bowl-to-carb mating surface..


See post 7 on my CVK issues thread below, for more details...

Assuming it is too low, perhaps you've found your problem.. If your level is correct, your problem lies elsewhere.,

 

Finally got a chance to pull the carb... float level looks spot on

What I did find was a float bowl full of garbage. Looked like a few strands of shredded tobacco (I'm an occasional pipe smoker). Have no clue how anything got in there as I've had a filter between the carb and tank for most of last year.

Anyway... bowl is now clean and I'll give her a rip this weekend and see if she runs cleaner. WOOT!

 

On second thought..... last major group ride back in early November, I stalled out in a creek crossing when the vent lines sucked up a bunch of water. That would explain how the junk got in the bowl. *grin

 

Happy to report she's running like a beast! (well, a little 250cc, CVK carbed beast!)

I've got an FMF 1-1/8" quiet insert one the way... I'll let you know how the lidless formula runs mildly stopped up once it arrives... *grin