Crf150r bog!:[

Hey guys I have a terrible bog problem on my crf150r I was wondering if anybody could give me advice. I live in Texas around 600-700 feet and I ride and munster and rockyride and some local tracks. I'm 14 and been riding since I was 5. Sorry if this has been posted before

Sorry I meant rocky ridge.

It has been posted a bunch, you should do a search because there are a few ways to solve it. I went with a 48 pilot and R&D power bowl with adjustable leak jet. Some people go 42-50 pilots, 40-50 leak jets, wire the return spring, quick shot and I'm sure a few other combination of ways.


First thing to do is drop in a 45 pilot ... costs less than $5. Adjust fuel screw to 2 full turns out.

Do the AP mod (o-ring) on accelerator pump. Go to hydraulic hose or auto supply store and buy an O-ring like a #78 O-Ring (7/16" O.D. X 1/4" I.D. X 3/32" thick).

VERY SIMPLE procedure (do a quick search on AP mod)

For only a few dollars and less than 10 minutes work, you'll probably fix your problem. :thumbsup:

I would suggest buying a few different size pilots because the your carb is going react different than other places in the country or even different parts of the same city, or even different times of the day. Like if a thunderstorm moves in and the humidity goes way up. Something that doesn't really happen here, but might there. But also pipe selection, some pipes might require a 45, some a 48. I have a DMC pipe and a 45 would be too lean. And the fuel screw just depends on the condition that it runs the best. Like the poster above lives in BC, and it might be 25 degrees or something so he might need to run 2 out. It's all about jetting it to your specif set-up and location. A bigger pilot ($5 each) get three different sizes just in case. Better safe than sorry, also get a 40 or 50 leak jet, and try the AP mod (wired or o-ring). I chose the R&D Power Bowl of the adjustable leak jet and the better AP pump. Plus the bowl is supposed to be different But I didn't really compare them. I do know my set-up works, no bogs out of corners, landings, through the whoops, and it has instant throttle response. I also get a deal on them so I knew it wasn't going to break the bank.

get us a deal on them! LOL, I've posted in another thread but socalxr is spot on, this is what everyone seems to be doing, I've ordered a 40 leak jet and we'll see if that takes care of my bog issue, if not i'll get a 45 pilot, I've got a 48 on the way to but that's too big I think.

I think it's a cold weather issue that is until I saw where this guy lives so there goes that theory.

a 48 pilot jet is working for me right now, but i still need to try a different leak jet. the ap mod did not work for me.

so i cracked open the carb last night and this is what I found, it's not stock in there.

135main, 42 pilot, and the stock 60 leak jet.

I gave it a good cleaning and after playing with the air screw for about 10 min, it runs like a champ, 99% of that low end bog is gone and it was only 32 degrees last night, I have the 40 leak jet on the way but for now I'm happy.

So give that baby a good cleaning I'd guess that's 90% of your problem, especially if the bog just started to happen, if that's the case then it's 100% of your problem.

Thanks everyone I'll be trying that out! I bought a 45 pilot last night.

So what's the update???? I cleared the bog out of mine by adjusting the air screw in, simple as that, because it was upside down I was actually turning it out not in... silly me. Now the bike runs like a champ, and good quality gas is a must, 93 octane.

today I dropped in the 40 leak jet and the bike ran like junk, I had to turn the air screw out 4 turns for the bike to even idol, so I slapped a 48 pilot in the carb just to see, and put the air screw 1 3/4 turns out and the bike is spot on, I live in indiana and i'm at 850ft above sea level.

48 pilot, stock main, 40 leak jet, air screw out 1 3/4 turns and I've reached perfection, the bike can practically stand still in first or second and just throttle out of it, no bog at all.

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