Hey guys, I've been lurking around here and with your help, decided to mod my horribly slow 07 KLX.

Mods are as follows

HMF Muffler
Four stoke works header
no airbox lid
Vented crankcase
Dynojet kit with 128 main (drilled slide and needle on 1st position with no spacer)
Air screw out 2.5 turns
Removed EPA crap and capped everything

Bike runs pretty damn good, once I can get it to start!! I think my problem is in my needle position.

See, my OEM carb needle did NOT have that brass spacer that is in everyone's posts and in the dynojet instructions, it had one kinda built into the needle. So, I did not have one to install with new adjustable needle. I guestimated the width of the spacer, and compared the OEM needle height to where I should put the clip on the dynojet needle. Needless to say, I put it on the 1st clip, with no spacer (i didn't have one) to make it as long as possible.

Like I said, the bike doesn't like to start, or idle well. It pops on decel, and I have to keep giving it throttle at lights, if it does stall on me, I have to use the choke to restart it. Seems to me like it is running lean everywhere. At WOT, it seems to run pretty decent, but still lean.

Advice, please!

 

why do you think its lean?
just curious

done a carb sync yet?
if you have to use the choke to restart it are you SURE that at that time the engine is Fully at operating temp?

dang I wish I had a computer and 4 Wide Band oxygen sensors to dial it in perfect!
sorry no help... just wanted to subscribe!

 

is it the stock pilot jet? have you tried adjusting the idle ****? a Dynojet 128 i think is too small for running with no airbox lid... probably should bump it up... and u said " I put it on the 1st clip," is that from the pointy end or the other end... if its from the other end id reccomend moving it down a clip or 2.

 

If the bike will not run when warm - your idle may be too low. This would also stop it from starting. I don't remember what jet I installed from the dymo jet kit- I put in the one they said to and my bike ran fine. I have a klx250s same stuff you have plus the fourstroke works muffler.

 

Your needle is all wrong. The spacer goes ON TOP of the needle. If you do nto have the spacer you are to use the two washers that come in the DJ kit instead--again ON TOP of the needle. Then set your needle at an appropriate groove. You made it horribly lean in doing this.

Dont mess with the idle or pilot till this is fixed.

 

wow, thank you for the fast responces!
For the record, this isn't my first attempt modifying bikes. When I was 16 I installed a 318cc stroker kit in my honda fourtrax 250x. I raced honda cars for years and tuned and built my own engines. I'm just really not good with this style carb and its whole "vacume crap"

Yes, the engine is at full temp when it won't idle. It is not something that the idle screw would fix, I would have to bump the idle to 2500 rpms to idle, which isn't right.

Yes, stock pilot jet. I think the 128 maybe to small as well, but it seems like its lean everywhere, that is why I think KLXer is right about the needle being all screwed up. I have it on the first clip from the TOP, furthest from the point. Because I don't have the spacer, or washers, I figured this position would put the needle in almost the same position if I did have the washer, and had it on the #3 clip.

KLXer, the thing is, I never had a spacer, or washer. Not one stock, and not one in the kit. If I put in the spacer, and moved it down a clip or 2, isn't that the same as running in position 1 without a spacer, if the overal length of the needle is the same?

I really do apperciate the help. I might actually see if one of my old fourtrax 250x/300ex pumper carbs will fit. They came with them stock and you can get them really cheap (50$ or so) if you look around.

 

Your needle is wrong, why didn't you just follow thedirections that came with the kit, they are very easy to follow and extreemly clear? If you do not have them, you can download the directions from the DJ website. The needle clip should be on the 3rd or 4th postition, depending if you have stock or aftermarket exhaust. The instructions are pretty clear about what to do if your bike has a stock spacer or now. Your needle is so low it is hardly lifting out of the main jet, that is why you are so lean.

 

I know nothing about jetting, but welcome to the forums you lurker. [sm=type.gif][sm=welcomesign.gif]

 

I did follow the directions, but I had no spacers, what so ever, either in the kit, or stock, so I had to think of the best setting to make it as close as possible without any spacers That is what I figured, since I don't have any DJ washers, I'll order a spacer from kawasaki and put the clip in the #3 or #4 position.

 

If you're sure your carb is assembled correctly, put the airbox lid back on. You will find it difficult to get enough fuel to offset the massive amount of air coming through that box with no lid. I ran the gamet of jetting on two carbs before giving up and using the lid without snorkle. I could get it to run well at WOT or midrange, but I always had trouble somewhere with the lid off. My bike is a 331, so I would expect the problem to be worse with the stock displacement. From that point, you should be able to work up and down the jetting scale as needed for best performance. Also, try the N1TC needle. It's easier to adjust than using shims under the stocker. ( Belay that last comment. I see that you are using the Dynajet with adjustable needle.) Rock on...

Hope that helps.

Bill Dragoo
Norman, Oklahoma