new here

[OasisQc]

Hey , im new here and im from montreal
( be cool my english is not perfect ! )


so i just got a 11hp Briggs engine. ( out from a cub cadet 1100)
there is the spec

Engine Type:	Briggs & Stratton 253417
 	gasoline
 	1-cylinder
 	air-cooled
Displacement:	399 cc [24.36ci ] 
Bore/Stroke:	3.4375x2.625 inches [87 x 67 mm] 
Power (gross):	11 hp [8.2 kW] 
Air cleaner:	dry
Rated RPMs:	3400
Torque:	16.8 lb-ft [22.8 Nm] 
Torque RPMs:	1575
Starter volts:	12
( it rev up to 3600 on engine cover

so my plan is to build a mower style kart ( not for mower racing just for fun )

something like this.
http://www.youtube.com/watch?v=ZAV2uQrnEFM

But im not familiar with this type of engine.
i juste want to have a reference about the clutch that i should use and the sprocket . i dont want a tranny. i will use real go kart wheel and tire.

i am a good welder and a machinist student.

 

[OzFab]

First off, welcome to the forum...

That kart is sweeeet, nice choice

Now, about your engine, is it a horizontal or vertical shaft engine? If it's horizontal, you're good to go; if it's vertical, you're gonna need a tranny of some description

EDIT: From the little research I've done, it appears you may have a horizontal shaft engine, good news for you.

Being that an 11hp B&S has a 1" PTO shaft, you'll need a clutch like this one

 

[OasisQc]

yes the engine shaft is horizontal. this is why i take this engine.

thank for the link but the clutch Engages at 2300 RPM .. it is not to high for a engine that only rev to 3600 ?

 

[OzFab]

That's just the first one I found, if you look around, you may find others. Besides that, the engagement speed is determined by the spring tension, a looser spring will provide a lower engagement speed

 

[OasisQc]

yeah a understand that , but what about the number of tooth ( or teeth lol ) on the engine and on the shaft. the tire will probably be around 10 inch of diameter.

i use that but i think this calculator is not good.

 

[DS13]

A good ratio to start with is 6:1, then adjust to what you want from there... more top end = 5:1, 4:1... more torque = 7:1, 8:1... or course it doesn't have to be a full number

 

[OasisQc]

thank for the advice. and what about torque converter ? ( cvt belt ) they cost a lot more but is this is su much better ?

 

[OzFab]

Nothing wrong with our speed calculator, the problem is probably the numbers you entered...

As DS13 pointed out, you can play around with the gearing to improve top speed or accelereation.

Whether you have a 2hp engine or a 22hp engine, with the governor intact & the same gearing, you will achieve the same top speed; the difference is how long it takes to get there.

The logical conclusion, therefore, is that a 12hp engine has twice the torque of a 6hp engine so, you can safely use higher gearing on the bigger engine which will give you similar acceleration as a 6hp but a much higher top speed...

As for a torque converter, you could use one if you're ready to fork out three times the price of a clutch which will give you better acceleration & a higher top speed

 

[OasisQc]

yeah cvt are very expensive.. and they have no spare part ?

btw i will go with a normal clutch just for the price

10 inch tire
3600 rpm engine
43 teeth on the axle
14 on the clutch 

35 mph ( 56kph )

this i looking good but what about the axeleration ? this engine got a lot if tq lbs .

 

[DS13]

yeah cvt are very expensive.. and they have no spare part ?

btw i will go with a normal clutch just for the price

10 inch tire
3600 rpm engine
43 teeth on the axle
14 on the clutch 

35 mph ( 56kph )

this i looking good but what about the axeleration ? this engine got a lot if tq lbs .

4.3:1 may be a little high for a normal clutch but im not sure... wait for fabro or someone who would know better

 

[OasisQc]

thank you guy you are fine with me . Did my english is good ?

im gonna pull out the engine from the tractor soon.

 

[OzFab]

4.3:1 may be a little high for a normal clutch but im not sure... wait for fabro or someone who would know better

4.3:1 might be ok but, those figures give you 3.07:1 which is starting to push it

Did my english is good ?

Well, er, it was ok, until that happened

 

[Doc Sprocket]

That ratio is far too high. You're going to want at least 72 or so on the axle, with a good quality clutch- more teeth still, with a cheaper clutch. If you were actually racing, you could probably get away with less teeth. The problem is, if you're just goofing off having a good time, you'll be slipping the clutch a lot, and that will burn it up fast.

 

[OasisQc]

72 on the axle ? that kart gonna be slow !!

 

[DS13]

You could go with a jackshift then

 

[OasisQc]

i just got 10 inch kart tire for free

EDIT : what is a jackshift ?

 

[OasisQc]

ok finally gor the tire 10x4.5x5 front 11x6x5 rear

gonna pull out the engine very soon and i will start a real build thread with picture.

http://www.ebay.com/itm/GO-KART-TOR...696?pt=LH_DefaultDomain_0&hash=item5af0755fb8

+62$ shipped. price is good.

 

[landuse]

72 on the axle ? that kart gonna be slow !!

If you don't gear it low like with a 72T sprocket, you are going to destroy your clutch in 5 seconds. It will overheat

 

[OasisQc]

i remove the engine from the lawn mower. I just accidently start the engine by trying to remove the Electric pto clutch .. LOL

I put the impact on the bolt. I try conter clock wise and clock wise and he just start in my house lol. That was funny

 

[OzFab]