E series with H series carb.

[JZ05220r]

I may have started a similar topic in the past. I have an H model carb in my E series. It runs great with the stock jets and needles for an E series. It will bog off the bottom if you go too hard. The bogging was for sure worse with the needle in the middle clip position but I’m now currently at the 4th from top clip position and need to look into a different needle. The difference in jet block height between the E and H carbs is the reason the e series jetting isn’t quite right. I’m thinking maybe whatever needle works well for the 200 H series should work well. CEL is what I’m thinking. Maybe CEK. The pilot and main are on point and the plug looks amazing. Just need to be able to get on it faster off the bottom. Anyone have suggestions? Thanks

[SS109]

I'm running the EK and love it. My bike pulls hard throughout the rpm range.

[JZ05220r]

I'm running the EK and love it. My bike pulls hard throughout the rpm range.

I will give it a try. Btw the carb on that bike is not an RB carb. Thanks

[John_S]

The air screw setting can make a big difference transitioning from the pilot to the needle. Before replacing the needle, try this if you haven't already...

With it fully warmed up, turn the air screw in 1/4 turn and try the acceleration you're having an issue with. Then go back to your current setting and turn it out 1/4 turn and test again. With that little test you've turned the screw a total of a 1/2 turn. If the pilot jet is correct like you're thinking, your bike will run significantly different with that much air screw adjustment. If you have an improvement somewhere in that range, then start making your adjustments 1/8 turns.

Depending on the humidity I'll have to tweak the air screw to tune out a bog coming off the pilot circuit. I'll be lugging in 3rd out of a corner and can tell if my air screw is lean or rich. Sometimes an 1/16 - 1/8 of a turn is all it takes.

[JZ05220r]

The air screw setting can make a big difference transitioning from the pilot to the needle. Before replacing the needle, try this if you haven't already...

With it fully warmed up, turn the air screw in 1/4 turn and try the acceleration you're having an issue with. Then go back to your current setting and turn it out 1/4 turn and test again. With that little test you've turned the screw a total of a 1/2 turn. If the pilot jet is correct like you're thinking, your bike will run significantly different with that much air screw adjustment. If you have an improvement somewhere in that range, then start making your adjustments 1/8 turns.

Depending on the humidity I'll have to tweak the air screw to tune out a bog coming off the pilot circuit. I'll be lugging in 3rd out of a corner and can tell if my air screw is lean or rich. Sometimes an 1/16 - 1/8 of a turn is all it takes.

Just tried this. When I turned it in a 1/4 turn from my current setting it still bogged. The idle also dipped very low almost stalling. I turned it back to my default setting and the idle came back up. It’s not so severe that the engine cuts out. It more so just a dead spot/borderline cutting out, and their wasn’t any smoke indicating a rich bog. Before I raised the needle up a clip, the bog was definitely more pronounced and actually caused a complete cut off in power. I’m leaning toward changing up the needle. Im leaning toward running a smaller diameter needle with a slightly bigger taper and smaller length. I will say there really isn’t a whole lot of smoke coming out of the pipe and I have had zero spooge. Runs excellent when riding it with less of a heavy hand.

[JZ05220r]

I tried the CGK needle. Same length as the BGP (stock e series needle) but more taper and a smaller diameter. Would just barely idle regardless of air screw setting. I didn’t mess with the idle screw though. Still could get it to run flat just off idle. Crawling in 2nd gear for example and quickly holding the throttle at 3/4, it will run flat, and in some occurrences bog/cut out and then catch up and rev out nicely. I was going to move up on the pilot but realized I am using a 48 pilot and based on what I have read the 50 pilot is too big. 155 main. I think a shorter needle length may be what I am after. I also consider the experience I have had with both my kdx’s and how i can’t really get on it hard at crawling speeds without a dead feeling or bog. I have always had to let it get on the pipe a little bit before really getting on the throttle.

[SS109]

Where are you at that you would need such a large pilot jet? I'm at a 38pj at 2000 ASL. I think your pilot jet is way too huge and is causing your problem.

[JZ05220r]

Where are you at that you would need such a large pilot jet? I'm at a 38pj at 2000 ASL. I think your pilot jet is way too huge and is causing your problem.

May be too rich to catch up with itself off idle is what I think you are suggesting. It actually idled great with the 48 pilot jet/stock jetting and was within 2 turns out on air screw. If I turned the air screw in a 1/4 turn in from where I had it it wouldn’t hold a reasonable idle rpm and idle very low. I will try that. However the bog was very pronounced with the stock needle until I raised the needle up a clip. I am at 800 ft above sea level when testing.

[SS109]

I would try a much smaller pj like a 42 or 40.

[JZ05220r]

I would try a much smaller pj like a 42 or 40.

I’ll give it a shot. I’m using the CEL needle now after coming from the BGP so that definitely richened up the jetting across the board anyway.

[JZ05220r]

Just tried the 42 pilot. It seemed to run over all a bit better down low. When I think about trying to get it to bog I can make it happen but when I am just riding normal it seems fine. Just have to stay alittle closer to the rpm in which the power valve begins to open, just off the pipe. I feel like it would be hard not to have the engine run mushy or maybe bog when going full throttle from the low rpm I am at. Like it would be a whiskey throttle machine if it made torque at basically idle speed. Overall I am very happy with the way the bike turned out after restoring it. This E series engine runs like a 4 stroke, roll on power builds and builds just right. My 220 was never like that but I am working on getting it right.

[John_S]

I’m glad to hear it you’re liking where it’s at. One final thing to try with it all the way warmed up is the same thing you’re doing but in neutral. You should be able to go from idle to wide open throttle as fast as you can twist with no bog. If you’re pilot and air screw setting are correct it’ll lean bog while it’s warming up but rev perfectly clean when the engine is at operating temps.

[SS109]

BTW, have you tried following the jetting guide here on the forum? That's what I have used for years to get my KDX's, or any bike for that matter, dialed in.

[JZ05220r]

Yes I have. Unless I’m doing it wrong, when setting the pilot based on the jetting guide, the 48, 45, and 42 all had a noticeable increase in idle within 2 turns out when turning it in and backing it out. Obviously I still had to fine tune from there. As for the main jet I just haven’t done any plug chops but Its feels good with the 152 in it.

[JZ05220r]

I’m glad to hear it you’re liking where it’s at. One final thing to try with it all the way warmed up is the same thing you’re doing but in neutral. You should be able to go from idle to wide open throttle as fast as you can twist with no bog. If you’re pilot and air screw setting are correct it’ll lean bog while it’s warming up but rev perfectly clean when the engine is at operating temps.

I didn’t really want to rev it like that while it was warming up but when fully warmed up it responded no matter how fast I gave it throttle at idle. I do think I am a tad rich on the needle. The BGP needle had absolutely no stutter rolling on. With the CEL for example, when I shift into second and lightly accelerate I get a tiny stutter. I may just lower the needle one notch to get rid of that but I think I’m fine either way. Alittle rich won’t hurt things. Here’s a cold idle of the bike.

[John_S]

That’s a really beautiful KDX with a great idle also. Congratulations on the build coming out so nice.

[JZ05220r]

That’s a really beautiful KDX with a great idle also. Congratulations on the build coming out so nice.

Thank you. I still have a few finishing touches, that being the white side panel decals and the unitrack swing arm decals. Just not sure where to find the template for the oem style side panel decals to send to Cormoto graphics.