New kart owner in CA

[Clinton]

Hello all! Just picked up a couple of street karts (minus engines) off Craigslist. Stumbled onto this forum while searching for parts and info. Looks like a treasure trove of good info here. I'm new to go karts. Never had one as a kid. Just motorcycles and then cars. My daughters were bugging me for karts so I found these projects. I bought two Harbor Freight 212 engines today. Hope they fit the karts.

 

[Doc Sprocket]

Shouldn't be too much trouble getting those engines on your karts, and we'll help you along. Welcome to the forum.

 

[OzFab]

They hook up pretty much the same as most other horizontal engine.

Having no engines, does that also mean they have no clutches?

 

[Clinton]

They hook up pretty much the same as most other horizontal engine.

Having no engines, does that also mean they have no clutches?

Correct. I was able to determine the sprockets used a #35 chain, so I ordered two 12 tooth clutch and chain sets for the 3/4" shaft engine. I think I got it right after checking out how to measure all that stuff.

 

[landuse]

Welcome to the forum. How many teeth have you got on your axle sprocket? If you divide that by your clutch sprocket teeth you will get your gear ratio. It should be at least 6:1 or a bit lower (higher number). Higher than 6:1 is generall not too good for the clutch as it slips a lot

 

[Clinton]

I think the the sprocket is stamped 72. The one on the other kart is stamped 77.

 

[landuse]

I think the the sprocket is stamped 72. The one on the other kart is stamped 77.

You should theoretically be OK if you have those numbers

 

[Clinton]

You should theoretically be OK if you have those numbers

Ok cool. The only problem I'm having with the sprockets is how close the ground they are, especially the 77 tooth. With a chain on it, there's hardly 1/2" of ground clearance. By the looks of it, I can tell the previous owner had hit pavement with it.

 

[landuse]

Ok cool. The only problem I'm having with the sprockets is how close the ground they are, especially the 77 tooth. With a chain on it, there's hardly 1/2" of ground clearance. By the looks of it, I can tell the previous owner had hit pavement with it.

Yeah, people have this problem with larger sprockets. That is why some karts use jackshafts. This allows you to use smaller sprockets to gain the same gearing. It allows for compound gear reduction. There is not too much you can do about it besides driving carefully or making a jackshaft for your kart.

You could probably get away with a 72T on this kart as weel it would give you slightly more clearance

 

[Clinton]

Yeah, people have this problem with larger sprockets. That is why some karts use jackshafts. This allows you to use smaller sprockets to gain the same gearing. It allows for compound gear reduction. There is not too much you can do about it besides driving carefully or making a jackshaft for your kart.

You could probably get away with a 72T on this kart as weel it would give you slightly more clearance

How small could I go on the sprocket before the the clutch begins to gripe about it? The tires are about 11"-11.5".

 

[OzFab]

You can try going as low as 60t but, be aware of the risks: If it seems like the clutch is working too hard from the get-go, don't push it

 

[landuse]

You can try going as low as 60t but, be aware of the risks: If it seems like the clutch is working too hard from the get-go, don't push it

I agree. A 60T will give you a ratio of 5:1 which IMO is too high. You have nothing to lose trying though, except the price of a new sprocket

 

[Doc Sprocket]

You could try a smaller sprocket. If that kart is small and light, and the driver's not too portly, you might get away with it. Drive around for a few minutes and feel it out. Does it pull okay from a standstill, or does it feel like it's struggling to get moving? After several starts, is the clutch too hot to hold onto with your bare hands? If it is, you're going to kill it.

 

[Clinton]

Ok, got it. Maybe iil try something like a 66t. My 10 yr old daughter will be driving this one so no too much weight there. The other one is a little heavier and will have an adult driver so I stay with a bigger sprocket, like the 72.

 

[anderkart]

Clinton, here's a link to a chart that lists the diamiter of all #35 axle sprockets: http://www.azusaeng.com/Sprockets/AzSDno35.pdf

That chart shows that swapping your 77 to a 60 tooth would only achieved around an inch of additional ground clearance... That'd help a little, but you'll find that even a 60 tooth would still hit the ground quite a bit when riding over bumps, rocks, curbs and stuff. So instead of replacing your sprockets, I'd sugest you simply instal some sprocket guards. They're made for karts that race on dirt tracks to help solve this problem.

The 9" Nylon pair (priced at $12.95) at this link would help protect your chain and 72-tooth sprocket: http://www.out2win.com/catalog/sprkt_acc.html

Larger sized sprocket guards (for your 77-tooth) are avalible here: http://www.cometkartsales.com/store/sprocket/guards.htm

Heres a pic showing tthe sprocket guards on one of my karts:
(another big advantage of instaling sprocket guards is they help keep your chain from flying off)

PS:
Those sprocket guards come with longer bolts/nuts and are super easy to instal. The aluminum ones are 2-piece, and then the lower cost nylon pair (I recommended above) have a split so they can be installed without removing the axle.

From the pic you posted it looks like they'll fit your kart, but just to make sure: They're made to fit hubs using this 6-bolt pattern:

 

[Clinton]

Wow, didnt know such a thing even existed. Now i know what all the noobs feel like on the model airplane and VW forums I frequent.
I'll get some of those nylon ones. They look like just the ticket. Thanks.