having trouble eliminating a low speed bog

[2-strokes-4-life]

my 125 has a problem as is if you are in a low rpm situation and snap open the throttle quickly it will bog down.i noticed oil under the flywheel so i changed the crank seal thinking that would fix it but its still doing it.i just started running 110 fuel in it and as of right now have the air screw at about 3/4 from completely closed needle clip in the the third position with a stock main.with the air screw at that setting it loads up to the point were it wont idle and i think it helped alittle with the throttle response but it will still bog.should i try a bigger pilot or does it sound like i have some other kind of prob?should the bike be able to acellerate cleanly from really low rpm to instant full throttle without bogging?

 

[NacNac250F]

Just to clarify, when you say it bogs do you mean it will just kill it if you snap the gas open or it will just be really slow and hesitate to go? Because race gas makes the motor run richer rather than lean out, and if you are bogging out then it would be a lean condition. What kind of bike is it and what year?

 

[2-strokes-4-life]

sorry for the lack of clarity on my part,2001 cr125.yes it bogs as in if i dont back of the throttle some and let the rpms rise it will eventually die. if i back off for a second or so and let the revs increase and then give it full throttle again it will accelerate smoothly.this only happens if im going really slow and suddenly give it full throttle.

 

[NacNac250F]

If it is right off of idle then you could probably fix it with your air screw. If you have to go more than two turns out from all the way in on your air screw then go a size up on the pilot.

 

[2-strokes-4-life]

ok,i went to the dealer and ordered a one size larger pilot.i guess the pilot it the prob since even with the air screw at 3/4 from closed it still bogs of the bottom.but what i dont get is with the screw at this setting it wont even idle because its loading up but it bogs as if its lean? if i turn the screw out to about 1 1/4 the bike will idle fine but bogs worse at that setting.does it sound like i need the bigger jet or could this be caused by something else?just for the info the bike has a clean filter,new piston/rings and a new left crank seal.any info will be much appreciated as i am stumped at this point

 

[usgpru27]

I also have an 01 CR125 and I had fits trying to jet it. If you have the original carb the book states like 2.5 turns out on the air screw. I use a 50 50 mix of C-12 and premium. Hondas are SO rich from the factory. They could run good in alaska. I went from a 45 to a 35 or 30 in really hot weather on the pilot. 2 to 2.25 on the air screw. 2 sizes leaner on the needle at a 70 or a 71 and a 360 main. I rode it last week on a really nice day and it ran great. Maybe like 65-70 deg and low humidity. I had the problem SO bad that you are describing that I would actually crash. I only trail ride in a really rocky area. Everytime I needed some power at low RPM to do some technical stuff BOGGG. Now I have none and it is actually very responsive and no detonation. I also have 2 stage reeds.

 

[2-strokes-4-life]

as far as i know the jetting in the bike is stock.i was told however that the cylinder head had been cut for more compression.if this is the case the jetting would need to be richened to compensate correct?if it hasn't, im hoping that is why i have the bog.these are the jets i was thinking of ordering:20-69 and 20-70 needle's, 50 pilot,40 pilot,390 main and a 370 main.do you guys think this is overkill or would getting these help to get me in the ballpark?the temps around here right now are ranging between the 60's and 80's.