All 2st throttle fail-'09 300WR

Caught an odd one this AM on the Mikuni. This carb spring[inside the slide] is stiffer on the '09 than in earlier 2T mikuni carbs. The throttle pull is a wee bit heavier. The surprise was when I inspected the steel cable housing that screws into the carb cap. The cable had cut right through the tube and was exposed for 10-12 mm. Not that many hours on the unit. Nasty. A hole for air/dirt!
New to me.

Yep, same here. I had this on my 11 WR250. Defo one to watch.

Replace with lectron real simple cheap mod, paid for itself in gas within two years!

had that problem as well..replaced the whole carb with PWK

found the same issue on mine recently, only has around 1500km tops. Was cleaning the carb out and relaised there was so much dirt on top of the slide, had me stuffed where it came from and then...

think it is because the throttle return spring is stiffer- more tension on the internal steel cable- I changed my spring and have a lighter throttle pull- could feel it on the first ride with this new to me 300- the throttle was too heavy- best dirt bike i have ever ridden btw!

What Spring did you change it to?

Ball point pen one?

Ahhh Juicy you always seem to make my day I love your smart a$$ sense of humor!

Don't encourage him Clay!

If i only make you happy my lifes worth living.

On a side note anyone felt the slide outta a berg fe400 03? Its made of brass an weights a tonne, dont think it needs a return spring unless it ends upside down.

Pardon the delay- just found this- I used a throttle spring out of an older TMX I had spare- same number of coils but slightly finer spring wire- feels a lot better to me- no arm pump