Hey Anciano, you gotta be careful thinking that fuel injection gives absolute altitude forgiveness. Only "closed loop" systems - all of which have O2 sensors - can provide "on the fly" altitude corrections.. The WR250R is not closed loop. It may be that it cannot sample ambient air pressure (barometric pressure) at all. The service manual for it seems to make no mention of barometric pressure being an input.. But I'm not starting or participating in a WRR discussion.

 

Hey, KLX678, with reference to my last post regarding frequent and significant altitude changes I did a little searching about Dial-a-Jet and after looking at numerous ATV forum discussions came across your pretty enthusiastic endorsement on this forum: https://www.kawasakiforums.com/forum...e-these-34472/

Are you still on board with DAJ? It seems like it might be a good choice for the type of riding I do. Do you have any idea of the range of jet sizes it emulates with its variable settings?

 

OK, but to adj "on the fly", you're going to need a kuoba screw. And once you get one, it is a piece of cake to "adj on the fly"... still don't matter whether it is a fuel or air screw. With the stock CV carb it handles elevation changes pretty good due to the fact that the pressure diff lifts the slide.

Also once you get a kuoba screw and do it once, you should remember which way to go on up & down elevations.

 

The easiest way to know how the pilot screw will effect mixture is to look at it's location in the carb venturi. If if is on the inlet side of the throttle plate or slide then opening the screw will LEAN the mixture. If it is after the throttle plate(like the oe carb on the KLX) opening the screw will RICHEN the mixture.

On FI bikes and autos that use only one pressure sensor the ecm will look at the pressure reading before you start the engine or when you go wide open to know altitude or ambient air pressure. That gives a fairly accurate signal and eliminates the complexity of two sensors.

 

The WR uses a MAP sensor to make altitude corrections. The ecm is able to see changes in ambient pressure during KOEO( key on engine off) or when the throttle goes wfo so that manifold pressure is equal to ambient pressure. That system works very well and can compensate for external changes on the fly. If a F/I system has an o2 sensor it can use a feedback system to maintain optimum a/f ratio.

 

well I got the jets in the other day and put in the 40, have not tried the 38, or 42
minimal deceleration popping, but even drilling my stock jet to a 40 solved that problem too
My popping later was due to exhaust leak which I didnt realize until drilling the jet even larger so that was my fault there for not checking over everything
why I decided to buy the real jet as its too hard to fill the pilot jet with solder and drill back smaller




I did get a little fuel screw tool but even the smallest one is still to long to fit, as it hits my starter
So I have to unscrew the throttle lines screw and spin carb over to adjust, which means I cant adjust with the bike running


I tried 3-1/2, 3, 2-1/2 and 2

every ride idle would fluctuate a little at a long stop light, no lower then 1500, but would start off at 2000
I could blip the throttle and instantly drop lower most times to 1500
then it could take 2 or more minutes then go right back to 2000
You can barely hear the idle change, but I could see it on the tach
Im pretty sure before it was always right around 1700 may have moved 1 tick here and there


now there is a chance it could of been doing this as for a while now I would only ride it in group rides and all the bikes were so loud I never paid attention
but lately ive had time to ride it by myself running errands when it caught my attention along with the popping but that was a leak causing that




I also replaced all the smog block off with new caps, with silicone too
and still dont have any intake leaks just incase it was those

if I have an exhaust leak at the header coupler I dont see any signs or feel any air so I think thats fixed now


I am very close to the 8000 mile valve inspection was thinking about getting that done soon maybe just to see if that does anything

and the black rubber valve cover? gasket one small section you can rub your finger on it and get oil
so I figure I can have that changed out with the valve inspection


I may get the extended fuel screw, ive only looked at one place
https://www.procycle.us/bikepages/klx250s.html#

then at least I can do it properly its just impossible on mine to do it running
header and the manual cam tensioner puts alot of stuff in my way


the only difference is the weather is just a little cooler then when I first did the exhaust and jetting mods

But its like maybe 10F cooler still in the 70's here or higher so its not like snow type weather

I dont think that could be an issue unless the packing has burnt out the muffler causing it to flow a little differently
I havent checked it yet