motor placement ?

[pearl111]

I heard you should move the motor as far forward as possible on a go-kart frame. I also heard you should mount the motor so that you have the shortest amount of chain possible. Where I have it mounted now, it has the shortest amount of chain. As the picture shows I have room to move the engine forward. If I do I will have to add more chain. Does ether way really make a difference? It's only a yard kart.

 

[itsid]

you can -especially on this setup- have the chain too short
chains like to stick to sprockets at speed, and therefore need a bit of slack to have the 'time' to break free

usually the clearance beteen the two sprocket shouldn't be
much smaller than twice the diameter of the smaller sprocket
and ideally not much bigger than twice the diameter of the larger sprocket
(very general rule of thumb.. with room for exceptions in special cases and slow running chain)

I'd say: it'd be safe to move the engine forward a bit.
say one or two full links added to the chain

keep in mind that you might need to remove the chain someday (say for engine maintenance)..
and it's easier if you can shorten the distance enough to slip it off the engine sprocket without opening it back up
(especially with rivited chain of course)

but if it's all set up already it'll be fine
I personally wouldn't bother to lengthen the chain if it's cut to that length for now,
if everything runs fine I'd leave it as it is for now;
once it's worn out and needs to be replaced I'd get a longer one though.

Only exception: if the chain runs especially noisy having not enough slack or
acts up occasionally (sticking and giving you a jerky ride)
in that case I'd add two more links sooner

'sid

 

[pearl111]

Great itsid this as always is good info. I will use. For this build and all my other projects also I believe this should help the life of the chain and sprockets. Thanks

 

[mcordell]

I have a similar question. Does the motor sprocket/clutch need to be in front of the axle or is it OK for it to be just slightly behind? I'd like more leg room.

 

[65ShelbyClone]

Well, we're not dealing with mid-engine race cars so put the engine wherever it's practical to put it. Placing it behind the rear axle will reduce weight over the front wheels and increase understeer, but it's such a small part of the total kart weight that I don't think it makes a lot of difference.

 

[mcordell]

You have a great point. Understeer is already an issue. Thanks for the quick reply.