First build ever!

[sied_wayz]

My first go kart build! I've been wanting to do one for years and this is the first chance I've ever gotten. I took a welding shop class this semester at college. I bought plans from spidercarts for the scorpion design and sort of made my own touches to it. I haven't finished it yet but here is everything so far!

This was the first I really did. I started by welding up the rear frame. It actually changed quite a bit from what you see here. I made some bad measurements because I ordered different parts from what the plans called for.

Here is the lower subframe of the front end sitting next to the rear end.

Here is the building of the chair frame. This part sucked. I needed a 67 degree cut and my saw only goes to about 50ish. So I had to do a lot of grinding and a lot of stacking beads to fill the gap but it came out sturdy!

Here's the engine I'm using. It's a 212cc 6.5hp predator from harbor freight. Atm it is stock, but I love to build engines. I teach an engine building class at my college and we go from small Briggs engines up to the 454 I'm building now. My plans for it are a new cam and a metal cam gear to replace the plastic one, 26lb springs, aluminum billet flywheel, exhaust, and intake, and ported head. That's about all I really want for now.

After UPS Royally pissed me off and two weeks passed by, I finally got a big box of parts!

Parts assembled

Here is the update on the rear frame with one of the hangers welded in place. (Vertical welding is my specialty)

There's more to come! I still have to decide between a torque converter and a clutch. I also still need to decide on a suspension set. After that, all I need is a steering column and pedal cables and then it all just comes down to installation! I'm so excited for this kart.

 

[KartFab]

There's more to come! I still have to decide between a torque converter and a clutch..

hey man, its really an obvious choice. Here are your options

1)clutch: slow, doesnt climb hills well, poor torque, lube very time you drive it

2) torque converter, 2.5 times faster, 3x the torque, minimal cleaning.

price ranges nowdays (thanks china) allow you buy a torque converter kit for about $130

 

[BirdFanatic]

hey man, its really an obvious choice. Here are your options

1)clutch: slow, doesnt climb hills well, poor torque, lube very time you drive it

2) torque converter, 2.5 times faster, 3x the torque, minimal cleaning.

price ranges nowdays (thanks china) allow you buy a torque converter kit for about $130

not trying to be a buzz kill but there is one down fall no matter how much performance you add to the engine it will always be limited to 45 mph where a cc can go well over .

 

[KartFab]

not trying to be a buzz kill but there is one down fall no matter how much performance you add to the engine it will always be limited to 45 mph where a cc can go well over .

Bird, this is an offroad kart. He needs the torque, and a centrifugal clutch and industrial engine that is geared to go over 25 mph (on a light kart) will burn up. Sorry man I'm going to call you out on this one. So lets be clear here.

1) gearing+rpm limits top speed, not the clutch or torque converter itself. The clutch and torque converter is only part of the equation
2) torque converter multiplies (not adds, MULTIPLIES) your gearing by about 3x upon start, then reduces it to .9:1 when you are accelerating so you get 3x torque and can have a nice top speed. When geared correctly, there is minimal slipping with a torque converter belt on start so you get more torque to the wheels.
3) centrifugal clutches do not modify your gearing, so you do not get the torque on start, only a portion of the available torque on start is transferred to the chain because the shoes on the clutch are slipping (hence the burning up if you want to gear it for a high speed, and the low torque on start). Thats why centrifugal clutches are bad for off road karts.

Bird, If you want to be taken seriously when speaking you need to say relevant, useful, and factual information (you know the stuff everyone automatically knows is true if they know anything about karts).

Again, a centrifugal clutch is a big no no for an offroad kart, unless you want to use a jackshaft reduction and go about 15 mph. That is fact, and that is generally accepted by most people. There are always going to be those out there that think otherwise, but it does not change the facts.

To FURTHER emphasize this here is WHY i am saying what I am saying

1) i have seen with my own eyes that centrifugal clutches on small go karts with industrial engines (like the engine he showed a picture of) are geared for a 7:1 or 6:1 ratio for these karts. They only go about 22-25 mph and do not climb hills nor can do any off roading

2) i have SEEN with my own eyes that off road mini bikes (baja200) have a compound jackshaft reduction to give the bike hill climbing ability and a top speed of 15-17 mph

3) i know that this kart of his is larger, and heavier than both the karts that i have seen and worked with, it has rear swing arm suspension and front suspension so i know that its going to go off road, hence the 15 mph comment for off road use

4) i have restored 10+ off road go karts that are geared for anywhere from 28 to 35 mph that are comparable in weight, size, and engine displacement to what he has. NONE of which had centrifugal clutches.

5) I have read countless threads of new and experienced people on this forum asking "why is my clutch smoking/burning up" only because they installed a centrifugal clutch on a large go kart meant for off roading (that i suspect originally had a torque converter on it)

BirdFanatic, that is why i dont take your comment seriously. Please feel free to explain using facts and experience that are relevant to the original posters situation.

 

[sied_wayz]

Thanks for the help! So do you think I can make 45mph with the torque converter?

I will be doing a lot of blazing through trails probably maxing aroun 25-30 but there will be plenty of times where I'd like to be doing 45 or faster because this will see some street use out on back roads. I will have a set of knobby tires and sticky tires for each situation.

 

[alexV]

Great build so far. I recently started on my own spidercarts go-kart, the arachnid, and transmission is indeed a big question.

If this is any help: I use a wet clutch instead of torque converter, with a 7:1 fixed gear ratio on 19 inch tires, 270 cc Honda engine. Should max at 28 mph. TC are simply not an option in this side of the world., so the best advice from this forum was about the gear ratio.

In my opinion, you will enjoy the kart alot either way

 

[firemanjim]

Get a TC......

 

[MatthewD]

Just to put my little point here.

I have an offroad kart, with 4.8:1 gearing, 145/70/6 tyres and a centrifugal clutch. For the general offroading that I do, this is fine, although I am looking to change it to a 5.4:1 ratio. The reason I haven't got a torque converter is because there wasn't sufficient room for it.

Now, I agree that you will burn out clutches, but this is the way it comes stock and I see nothing wrong with it.

I do confess that the take off is quite slow but it's not that bad really.

 

[firemanjim]

MatthewD, switch to 5.8:1 or 6:1.... I'm running 5.4:1 and you would want more oomph down low than what I have, at least for light off road use. My clutch gets hot just driving through 6-8" tall grass.....going just over clutch lock up rpm. I'm using a modded gx160, so it's not a lack of power......

 

[chancer]

Ok you guys have beat the gearing thing to death, So... With all those engine mods billet parts etc. Why no mention of removing the governor, that will get you 1500-2000 more revs equaling a higher top speed for the back roads.

 

[BirdFanatic]

Bird, this is an offroad kart. He needs the torque, and a centrifugal clutch and industrial engine that is geared to go over 25 mph (on a light kart) will burn up. Sorry man I'm going to call you out on this one. So lets be clear here.

1) gearing+rpm limits top speed, not the clutch or torque converter itself. The clutch and torque converter is only part of the equation
2) torque converter multiplies (not adds, MULTIPLIES) your gearing by about 3x upon start, then reduces it to .9:1 when you are accelerating so you get 3x torque and can have a nice top speed. When geared correctly, there is minimal slipping with a torque converter belt on start so you get more torque to the wheels.
3) centrifugal clutches do not modify your gearing, so you do not get the torque on start, only a portion of the available torque on start is transferred to the chain because the shoes on the clutch are slipping (hence the burning up if you want to gear it for a high speed, and the low torque on start). Thats why centrifugal clutches are bad for off road karts.

Bird, If you want to be taken seriously when speaking you need to say relevant, useful, and factual information (you know the stuff everyone automatically knows is true if they know anything about karts).

Again, a centrifugal clutch is a big no no for an offroad kart, unless you want to use a jackshaft reduction and go about 15 mph. That is fact, and that is generally accepted by most people. There are always going to be those out there that think otherwise, but it does not change the facts.

To FURTHER emphasize this here is WHY i am saying what I am saying

1) i have seen with my own eyes that centrifugal clutches on small go karts with industrial engines (like the engine he showed a picture of) are geared for a 7:1 or 6:1 ratio for these karts. They only go about 22-25 mph and do not climb hills nor can do any off roading

2) i have SEEN with my own eyes that off road mini bikes (baja200) have a compound jackshaft reduction to give the bike hill climbing ability and a top speed of 15-17 mph

3) i know that this kart of his is larger, and heavier than both the karts that i have seen and worked with, it has rear swing arm suspension and front suspension so i know that its going to go off road, hence the 15 mph comment for off road use

4) i have restored 10+ off road go karts that are geared for anywhere from 28 to 35 mph that are comparable in weight, size, and engine displacement to what he has. NONE of which had centrifugal clutches.

5) I have read countless threads of new and experienced people on this forum asking "why is my clutch smoking/burning up" only because they installed a centrifugal clutch on a large go kart meant for off roading (that i suspect originally had a torque converter on it)

BirdFanatic, that is why i dont take your comment seriously. Please feel free to explain using facts and experience that are relevant to the original posters situation.

Sorry didnt see anything in the first post about being an off road kart to me there is not picture of shocks in the pictures posted or even a place to mount them .

 

[sied_wayz]

Ok you guys have beat the gearing thing to death, So... With all those engine mods billet parts etc. Why no mention of removing the governor, that will get you 1500-2000 more revs equaling a higher top speed for the back roads.

Governor is already gone lol. First thing I did after I ran it on the test stand for the 3 hour break in.


But I've made my decision, torque converter it is. Please, no more gearing posts! I've had about all I can handle haha.

 

[CoroTheCat]

Looking good McDoubleByPass

 

[OzFab]

Sorry didnt see anything in the first post about being an off road kart to me there is not picture of shocks in the pictures posted or even a place to mount them .

Your reasoning is irrelavent, a TC is always better than a CC...

 

[firemanjim]

Your reasoning is irrelavent, a TC is always better than a CC...

Pound for pound....... Ayuup......