Hey guys , I just noticed that my dyna box on my 05 700 prairie is going bad . It worked fine for the past 2yrs and it just started low end sputtering and back firing .
The machine is low hrs , has a few clean mods , pro circuit full system , mild jetting , air box mod ...
Plugs looks good , I replaced them any way still ran like crap ... I swapped out the factory box and the quad was fine .. the carbs clean , nothing changed but runs fine now .
I guess the box has to go back to dyna ... any one else run into a problem like this ?

Thanks

greg