Jump to content
Sign in to follow this  

Ktm 250exc spooge problem!?

Recommended Posts

I have a 99 ktm 250exc and have been battling spooge for a while now. I just replaced the right side crank seal as I found the o-ring was missing from behind it causing it to spooge insanely bad! The crank bearings had absolutely zero play from what I could feel. Replacing the crank seal has helped some of my spooge but there's still a lot running about 3/4 of the way down the silencer. I'm running a 42 pilot jet with the air screw 1.5 turns out, a n85c needle and a 170 main and 50:1 with amsoil interceptor at sea level. I trail ride with some higher speed stuff but a lot of technical as well. My bike has a fmf fatty pipe and an fmf silencer (don't know which exactly) which has the turbine type spark arrestor. I've heard that spark arrestors can cause a bike to spooge, but have also heard that the older ktms ran rich in the low to mid range and a yamaha needle would help significantly. Do any of you guys have any tips, suggestions, ect? I don't mind a little spooge as it's a 2 stroke and some is normal, I just don't want a bunch. Thanks.

Share this post


Link to post
Share on other sites

How long has it been doing this ? pilot is usually the culprit in a spooge athon . you should jet by your plug not pipe . takes some time . mark your throttle in 1/4" increments using a fixed point on the housing. start doing some plug chop readings. 0-1/4 pilot  1/4 -3/4 needle  3/4 - full open main keep in mind they overlap.

Share this post


Link to post
Share on other sites

And repack the pipe when you get it jetted correctly, all that spooge built up in there isn't healping your cause, it has to have some place to go so it dribbles out the pipe.

Share this post


Link to post
Share on other sites

  • im running a 168 main and a 40 pilot with a stock needle on a 01 300exc at about 900 feet above sea level. I have bought a necj needle 165 main and 35 pilot im going to try. I would say try lowering the pilot and raising the clip on the needle to lean it out on bottom. Im in the highest clip now on the stock needle. Hope this helps.

Share this post


Link to post
Share on other sites

Had similar issue with my300, changed clutch side crank seal, still had the problem. Finally split cases found a bad clutch side main brg. I could not feel any play even with the jug off but it was roasted.

Share this post


Link to post
Share on other sites

Here is the jetting chart for your bike. You bought a 'C' needle. The other numbers and letters are the taper but the letter on the end is the diameter of the needle. At sea level the 'C' needles are good from about 60° to about 100°. That is pretty optimistic for one needle to cover that much range in temperature. Because the taper is different than the stock KTM needle it will change the idle jet size and the air screw setting from what is listed on the chart.

I run the FMF turbine core sparkys on all my bikes. They do make your bike run really fat. I jet two steps leaner than the KTM chart says to compensate for this on all my bikes.

Good luck.

99KTM250-300mxc-excJettingChart_zpsd6215

Share this post


Link to post
Share on other sites

Thanks a lot guys! And i rode it for a good 2 hour trail ride today, and when I got back it only had about a 1/4 inch line that ran about 2 inches down the end cap. I did repack the silencer, but I think it's just taking a bit to run all the oil that's stuck all in the pipe, not just the silencer.

Share this post


Link to post
Share on other sites

If I can remember the old ones have a # 6 slide ...if so that and the n85 needle is not good.

Try a # 7 slide and Nedw

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

Sign in to follow this  

×