Yerf dog 3202 buggy project

[smgs92]

well the sprocket i got is actually for when i switch to the cvt, but i can run the stock sprocket which would give me a ratio of 4.3:1. which would be a bit closer but there wasn't alot of options for clutches. and is 4:1 that bad? i thought 5:1 was a standard ratio

 

[peterbilt]

I wonder if the bucket seat you are using on yours would fit in my 3203? I also dig the air filter setup also. The build looks great!

 

[OzFab]

is 4:1 that bad? i thought 5:1 was a standard ratio

No, a good "balanced" ratio for a small kart is 6:1 but, since you have big tyres, I'd be heading for 7:1

 

[smgs92]

it was just a jegs racing seat i had gotten for free from work i had to custom make the bracket but the 3203 and 3202 are essentially the same kart. but you won't have room for 2 seats.
when i get the cvt i'll make sure to properly adjust but for the clutch i knew the bigger tires would be difficult so i'm planning on just running the stock 18in tires.
i'm getting the kart running then fixing the issues and installing bigger tires, hydraulic brakes, rack and pinion ect..

 

[smgs92]

minus the fact my buddy cut the chain 1 link 2 short -.- its ready to run with my 212cc predator it looks soo tiny on that kart though

 

[smgs92]

got some pics ran her for abit with the 212 but the engine felt too small for it and struggled in the mud but i think that was more the clutch and too tight of a chain ( it was either too tight or slipping off) but once i get the new plate for the 420cc i shouldn't have any problems

 

[smgs92]

looked at my mini bike and gokart today realized i could pull the 72t off of there and put it on my kart and put the 54t on the mini bike then i'll buy a 10t clutch for it but i wanted a smaller sprocket for it.
that should help my gearing a lot and atleast give me a ratio of 5.1:1 till i get my cvt

 

[smgs92]

So my next plan for this kart besides obviously installing the 420cc is. I'm going to cut those ugly flattened steel tabs they bolted the roll cage on with and weld the cage solid and widen the top of the cage out. Reinforce what parts need it.
Then weld up a chain guard and move on to making dual A-arm front end with probably 16in suspension and 20in tires.
After that convert it to independent rear suspension possibly add reverse not sold on the idea because I want to be able to take jumps and drive it like a quad.

I'm also going to run a snow mobile torque converter I found an adaptor for a 1in shaft. I like these because they're roughly the same price as a comet 40 series but as my engine gets built more it can be adjusted and handle all the power I throw at it.

 

[realfast89gt]

Yeah, a 4:1 is not a good idea. It will be a waste of time and money spent on the clutch you bought

I know this for a fact. My bro had a tec engine pushing about 10hp and that extreme duty clutch was a waste of money, after 10-15 minutes of riding it would overheat and barely move the kart. Even with a 6:1 ratio on my bros kart that clutch wouldnt last. Go tav or dont expect much. We even tryed a $100 fury clutch and with big tires it was a waste.

 

[B man]

So my next plan for this kart besides obviously installing the 420cc is. I'm going to cut those ugly flattened steel tabs they bolted the roll cage on with and weld the cage solid and widen the top of the cage out. Reinforce what parts need it.
Then weld up a chain guard and move on to making dual A-arm front end with probably 16in suspension and 20in tires.
After that convert it to independent rear suspension possibly add reverse not sold on the idea because I want to be able to take jumps and drive it like a quad.

I'm also going to run a snow mobile torque converter I found an adaptor for a 1in shaft. I like these because they're roughly the same price as a comet 40 series but as my engine gets built more it can be adjusted and handle all the power I throw at it.

Snow mobile TC wont work. your engine wont rev high enough to engage it. just get a 40 series.

 

[exenos]

A sled engine clutch system will work, Just need to re-clutch it to engage whenever you want. ( weak straight spring and heavy weights. Make sure you don't use notched weights if you want a low engagement)

 

[B man]

A sled engine clutch system will work, Just need to re-clutch it to engage whenever you want. ( weak straight spring and heavy weights. Make sure you don't use notched weights if you want a low engagement)

yeah, but why do that when you could just use a ready to go 40 series.

 

[Doc Sprocket]

With a sled CVT even fit the 420's PTO shaft?

Also- don't let your "roll cage" modifications lull you into a false sense of security. Even welded and gusseted, it's still cheap tube, and engineered to be a "brush guard". You're about to add more horsepower and of course you'll use it. But if you go over, that tubing's going to fold like a cheap suit.

 

[realfast89gt]

With a sled CVT even fit the 420's PTO shaft?

Also- don't let your "roll cage" modifications lull you into a false sense of security. Even welded and gusseted, it's still cheap tube, and engineered to be a "brush guard". You're about to add more horsepower and of course you'll use it. But if you go over, that tubing's going to fold like a cheap suit.

I am curious? If you had a cheap suit would you fold it? Are you even supposed to fold suits, or hang them up?

 

[smgs92]

Snow mobile TC wont work. your engine wont rev high enough to engage it. just get a 40 series.

Stock yes it will only rev up to 3600rpm but I am going to buy a clutch without the springs I found a both off almost new snomo's for $110 compared to the $200 40 series that won't hold up to the power I'm planning on making.

yeah, but why do that when you could just use a ready to go 40 series.

1 reason is a $90 price difference, and when I'm done I'll have to upgrade anyway the 40 series won't hold up to the power.

With a sled CVT even fit the 420's PTO shaft?

Also- don't let your "roll cage" modifications lull you into a false sense of security. Even welded and gusseted, it's still cheap tube, and engineered to be a "brush guard". You're about to add more horsepower and of course you'll use it. But if you go over, that tubing's going to fold like a cheap suit.

I think it was a page or 2 ago I posted the adaptor that someone who did the same thing recommended me. I have considered upgrading the cage now but I eventually will. I am welding a large bar of flat steel on the back of the cage to bolt the back of the seat and it will help with "folding". I could do the same to the front.

 

[B man]

Stock yes it will only rev up to 3600rpm but I am going to buy a clutch without the springs I found a both off almost new snomo's for $110 compared to the $200 40 series that won't hold up to the power I'm planning on making.

1 reason is a $90 price difference, and when I'm done I'll have to upgrade anyway the 40 series won't hold up to the power.


I think it was a page or 2 ago I posted the adaptor that someone who did the same thing recommended me. I have considered upgrading the cage now but I eventually will. I am welding a large bar of flat steel on the back of the cage to bolt the back of the seat and it will help with "folding". I could do the same to the front.

Won't hold up? I don't know what your planing, but i guarantee that the 40 series can handle any amount of hp thrown at it from a 420 with ease. They have been pushed up to 25hp no problem. If your "modified" 420 could even get 20 hp.

 

[smgs92]

Are you kidding me? Do you not know anything about these engines? They can make 50-60hp. I'm planning on at least 30hp which a comet 40 series would not hold up.

 

[slipknot23]

and what 420cc motor you using???

 

[smgs92]

Harbor Freight gx390 clone. You can look it up on youtube a lot of mini bike racers use them.

 

[OzFab]

If it's possible to get 50hp from a 5hp B&S, I don't see a problem getting that much from an engine twice the size

5hp B&S geometry putting out about 50 hp.

http://www.diygokarts.com/vb/showpost.php?p=250908&postcount=4