How to change the counter shaft sprocket

+1 This is how I used to do it on my old DRZ; hold down brake with right foot and lean over bike with an impact wrench.
I don't know about the new huskies, but on the DRZ's, leaving the bike in gear could cause the primary nut to back off when you zapped the CS nut with an impact.
You can also just put a block of wood thru the spokes on top of the swingarm to hold the rear wheel.

ray_ray off is counterclock, like a normal bolt,and it's a -itch without an impact, for some reason it was the hardest sprocket nut i have ever gotten off, and i've been riding for 41 years.

Where in Jersey are you? I have an impact and have also taken some tough ones off just by using a block of wood to keep the rear tire from moving. I'm in Vineland...let me know if I can help.

Unfortunately I live in the total opposite side in Northern NJ (bergen county). Thanks for the offer though!

cool ... I was thinking they might have reversed the threads to help keep the nut tight while riding ...

I've found other nuts on my bike very hard to remove the first time also ... I guess this is better than having loose ones ....

Probably not a hard and fast rule.

BUT

Chain on left side of bike countershaft has right hand threads.

Chain on right side of bike countershaft has left hand threads.

That keeps the nut tight while riding.

I road my 510 with the 12 tooth CS and what a difference it made! Low speed riding was much easier, not needing to feather the clutch lever as often. Mid-speed was improved too, the bike was more in the power band. On pavement it tended to rev-out still earlier, but the bike has a close ratio tranny. This is one advantage the EXC bikes have over the TEs.

Here's a trick i discovered myself stuck in the bush. Remove guard. Put a 22m ring spanner over the nut, facing up so that the other end of it is wedged against the frame. It is a normal thread. Bike in neutral. Lift rear wheel or lay the bike over and using your hands on the rear wheel, turn the wheel backwards. The chain will turn your CS sprocket and transmission backwards, your spanner and nut stay still, therefore your nut will unscrew! You can reverse the process for doing it up.

Old post, I know, but just had to award you the internet for it.

Genius.