Do they have the little screws on the throttle that if you turn it out it opens up the engine and if you turn it in it detunes the engine?

 

Only on the youth models on outside of throttle assy is a small screw and locknut to limit throttle.

 

Can an aftermarket be bought and installed?

 

ANYTHING POSSIBLE! Have one customer that bought 2 500 Sportsmans, installed twist grip throttle,slid original throttle assy down,from the twist grip had a small line that went into thumb throttle that he drilled a hole through and operated like a motorcycle! Told him several times he's asking for trouble,BUT cant talk sense to some old Texas rednecks!

 

Is there a good, reliable kit available? This thing has way too much go to let my teenage kids or wife ride as is. I hope to buy a smaller machine for them next year

 

Maybe you could repalace with a throttle assy from a Polaris youth model,not sure though.

 

The 400 is def not a beginers bike.You may want to look for a 250 or a 330

 

where theres a will theres a way,you could make an adjustable stop with a hardware bracket some epoxy glue and a small bolt+2 nuts and alittle knowhow....