Predator 212 Speed Reduction

[XanderWiFi]

This post is probably the opposite of what most people desire of their engines. I am restoring a childhood go-kart for my own kids and would prefer it not to hit the top speeds the 6.5 hp predator is able to produce (from video review). I am looking for ways to safely handicap the engine to increase the kids' familiarity before increasing speed. I would like to hear any other options people may know. Right now I am looking at the following:

1. Reducing idle speed. Would it help with movement speed at all?
2. Extra slack in the throttle cable. Can't get the speed if they cannot engage the throttle more.

Any other recommendations or suggestions? I would love to hear them.

 

[Mr_mcrib212]

there is a screw right next to the throttle lever, if you turn it so that it hits the lever, that will reduce the engine rpm.

 

[XanderWiFi]

Thanks much. What is this screw commonly called so I can look up visual aid and ensure I don’t start turning the wrong one? Lol

 

[itsid]

there is a screw right next to the throttle lever, if you turn it so that it hits the lever, that will reduce the engine rpm.

TERRIBLE IDEA!

the rpm range of any given unmodified industrial engine is miniscule
(2000 rpms from clutch engagement to 3600 max rpm)

limiting that is a really bad idea.. chances are the kids want to go "half throttle" at one point (cornering or such)
and the engine drops below engagement speed.. burning up the clutch.

nono.. don't

Instead. if you have a centrifugal clutch increase the axle sprocket.
that will slow the kart down and increase the torque (which isn't a bad idea at all.. since it allows for a more solid clutch engagement at slow speeds)

and in case you are using a series 30 TorgueConverter get the speed limiting weights pack
(it can limit the amount of spread the weights can expand to, thus limiting the ratio and resulting in a limited and adjustable speed.

'sid

PS if you insist on following the bad advice given and limiting the throttle.. make perfectly sure to limit to a value BIGGER than 2500rpm
(2800-3000 rpm is about as low as you could theoretically go)
and have a new clutch on speed dial.. I'd bet you'd need that sooner (not later )

 

[Mr_mcrib212]

ye sid's right didn't think of the clutch, try gear reduction gopowersports.com has some good cheap sprockets

 

[jamyers]

Gearing it down is best bet. Cheapest, too.

 

[XanderWiFi]

Awesome guidance. Thanks all.