Power Issues 2010 250EC
 

So I have combed the threads, and I found a few similar, but wanted to post my own with my own issue. here are the details:
2010 250 EC
185 PSI Compression
Brand new Pack on FMF Turbine Core
Fresh clean air filter
Kehein Carb
Fuel: 50:1 Motul 800 oil
Decent size dent in pipe (i think this has NOTHING to do with this)
Jetting:I can't remember the jet #'s but all of them are leaner than stock.
Spark Plug; NGK BR8EG, color looks slightly wet, but not horrible.
My problem is: i have absolutely ZERO mid range power. after 1/4 throttle its bogging VERY heavily til i get up into 3/4-full throttle, I moved the needle down one notch (it was all the way up) and even then its weak at best. I am also getting a TON of spooge (black) out the tail pipe already with the silencer freshly re packed. COnventional wisdom says its rich, but the plug tells differently and the bike is already jetted lean. I have heard crank seal, but i have no experience with this. any help is greatly appreciated. thanks guys!

Pull the pipe and make sure the power valve arm is correctly attached, these break on the early models. Then put just the pipe back on and run it to see if the power valve is moving under engine rpm.

Pull the pipe and make sure the power valve arm is correctly attached, these break on the early models. Then put just the pipe back on and run it to see if the power valve is moving under engine rpm.
Other than that do a leak down test on the motor, it will tell you if you are leaking oil in to engine via the transmission.

You can't tell squat looking at the plug. It's a roadrace thing for full open (mainjet) and only counts for a set test procedure.

Above good suggestions.

Then pull carb. Clean and blow through every hole and check hoses. Then with good light and a magnifier of some sort check you needle jet hole. The orifice should be round, not even slightly oval.

Then read what needle you have . If it's a N1FE or whatever std is that will be a large part of the problem. Moving it on the clip won't help it being too skinny to start with. Cut it in 1/2 so you're not tempted into using it again. Really.

Read the jetting threads here.

As F5 has already mentioned, it sounds like you need a different needle in your carb. Identify what needle you have and read through some of the jetting threads.

I've tried a few different needles but I've settled on a Suzuki NECW needle, it's running great, but mines an old 2004 EC300 with an AS1 PWK38 carb.

If you're in the UK or Europe and need any Keihin jets or carb parts I can recommend this guy based in Holland...

https://www.frankmxparts.com/

He also has a shop on eBay...

https://www.ebay.co.uk/str/frankmxparts

I've used him quite a lot, very helpful and great service. :)

All the best, Dave.

Okay thanks guys. Just an update:
Idle jet is a 40
Needle is an N1EG
Main is a 170

Haven?t Checked the power valve. Pretty new to 2T all together so I?m not sure how to check the ?arm? I guess seeing if the power valve moves freely? Sorry, and thanks!

Oh and idle screw is all the way in and the air screw is 3 turns out

Definitely try a different needle, myself and others have had success with the Suzuki needles. As I said before, on my old 2004 EC300 I'm using a NECW and another guy found the same needle suited his 2019 EC300.

See this thread... http://www.gasgasrider.org/forum/showthread.php?t=23994

All the best, Dave.

So a JD needle would work better? I bought a kit for my KTM 200 and it did absolutely nothing, felt like i wasted my $$, but with all the comments here it seems my needle might be my problem.

on another note, the guy i got it from said it needed to be HOT to run right. I have not been able to run it for more than 10 minutes at a time, is this common with the bikes? Thanks again so much guys.

For sure, please try a different needle.

I've heard good and bad reports about the JD jetting kit, my own personal opinion is you'd be better buying a selection of 2 or 3 Suzuki needles, think this would work out better value.

Try the NECH and NECW and NECJ.

No, your bike doesn't need to be run HOT. Just get it warmed up gently before you give it any hard acceleration or high RPM but once it's up to normal running temperature it will perform fine...as long as it's jetted nicely. :)

All the best, Dave.