2010 EC300 or not?

[Jakobi]

http://www.gasgasrider.org/forum/showthread.php?t=9517

Lots of good info here

Double that. Its a sticky in the 2T Engine section. Always at the top of the page. The process is simple. Drain coolant, drain trans oil, remove the pipe and the brake pedal pivot. Remove the pri side cover and pv cover using an 8mm socket. Allen key is used on the pin that attaches to the governor setting. Set it up so that the plate pushes up against the stop under its own force. Reinstall everything. Job done.

 

[Boom Boom]

Double that. Its a sticky in the 2T Engine section. Always at the top of the page. The process is simple. Drain coolant, drain trans oil, remove the pipe and the brake pedal pivot. Remove the pri side cover and pv cover using an 8mm socket. Allen key is used on the pin that attaches to the governor setting. Set it up so that the plate pushes up against the stop under its own force. Reinstall everything. Job done.

BINGO !!!!
Not that bad of a wrench job and well worth the results.
If the case does not come off easy odds are it is the case allignment pin close to the water pump. My pin was seeing a little antifreeze slipping by the original gasket and was a pain to get free. Worth pulling the case just to make sure your case does not have a failing gasket.
The allen that pinches down on the PV pin was not snug on mine and was allowing it to slip. As my exhaust flapper gathered some carbon it just worked worse till I had to open it up and have a look.
The exhaust flapper (where the rod connects thru the flapper) had poor castings and would not allow nice smooth action. A little time with a file and all smooth now and works great. Should have pulled the case long ago. I felt the bike worked OK before but now I am very happy.

 

[Jim Cook]

I have three things to add to this thread:

With the stock carbs, definitely get a different jet needle. If you stay with the same series needles, go to the N1EG and try the second groove from the top for starters.

For squish band and head mods, I highly recommend Ron Black, of RB Designs. ( www.rb-designs.com )
After he worked on the head of my 2006 DE300, I found it prudent to add a 10oz flywheel weight for better control in off-camber rocky single track situations. Plus, the fuel mileage almost doubled from before the mod.

When working on the bike with the right side cover removed, and the bike on it's left side, make sure to support the bike so that the gear shift lever is not bearing weight. (I usually do this when I work on the clutch, and use a "floor jack" under the left footpeg as I lay the bike over.) If the gear shift lever is supporting any weight, the right end of the shift lever will move enough to keep the side cover from seating properly.

Good Riding and Wrenching to You!
Jim


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[Beta Steve]

300

After you get the rb head mod, go to jd jetting http://www.jdjetting.com You'll find it to run WAY better with these two cheap mods...

 

[Jakobi]

How is JDs kit cheap?? You could buy a $12 needle from KTM/Suzuki and get it just as good.. if not better.. JD makes a good kit that gets you in the ball park reasonably quickly and easily. I found his needle worked stellar in my 250F but I've found better combinations on the 2T using OEM needles.

 

[estwudsracer]

I sent my head and carb to Ron @ RB Designs in Oregon. It is now the best, most cleanest running bike I have ever owned. Strong-Fast-Smooth-Amazing! I have had several orange bikes before GG, AND I race against a sea of them here in the S.E. I love blasting by them. It was the best $ I ever spent on a dirt bike.