Flathead twin go kart build

[u500771]

Because i have summer break and probably will be working on my go kart almost every da, I‘ve decide to start a little build log. Today was a pretty good day because i found the stationary engine version of the engine i already have (the main difference is the oil pan. On the stationary one it has mounting bracke in the corner like an old grinding machine or vice). I quickly bought it and picked it up. Gianni and I ha decided that we completely disassemble the two engines and build one for the go kart with the better parts and one out of the remaining parts to sell again. There came also a fan housing with the new engine, so i don‘t need to improvise that myself.

Here you can see the new oil pan that doubles as mounting points (the old oil pan is the silver thing with the gasket in the top left corner).




Those are the partly disassembled engines. The one on the right i‘ve bought last year and its cylinder block/head and valves are in way better condition than the one i bought today. We are going to use the block, head, valves, pistons&connecting rods and the camshaft from this engine. The oil pan, flywheel and the crankshaft will come from the other one because it has almost the same ignition than the mofa‘s we have in Switzerland (those are small 50cc motorcycles that will do something like 19mph and you are allowed to drive them with 14). The next thing to do is taking out the crankshaft of the engine i bought today and disassembling the one i already had. I‘m also going to remove the rev limiter which is set at 3000 rpm.



Here you can see the new fan housing. Its made from cast aluminum and i think I’m going to polish it before i the go kart is finished. My hand also gives a little bit of comparison on how large the engine is.
On what chassis/frame would this engine look the best? Please tell me your suggestions

 

[BaconBitRacing]

Look best? Something like this:
Or this:
But these Rupps are beautiful (and expensive) karts what ever engine is on it. You could build a custom frame similar to a Rupp if that's what you want. But truly, these aren't the most practical. They have little leg room and will break your back over bumps. We have comparatively few members that prefer driving this style of kart over bigger, more comfortable karts, Namely Hellion. Panchothedog, redflash, etc. like the suspension karts best. Are you building or buying? No suspension is easier to build and cheaper to buy.

 

[u500771]

Look best? Something like this: View attachment 140273
Or this: View attachment 140274
But these Rupps are beautiful (and expensive) karts what ever engine is on it. You could build a custom frame similar to a Rupp if that's what you want. But truly, these aren't the most practical. They have little leg room and will break your back over bumps. We have comparatively few members that prefer driving this style of kart over bigger, more comfortable karts, Namely Hellion. Panchothedog, redflash, etc. like the suspension karts best. Are you building or buying? No suspension is easier to build and cheaper to buy.

I thought about building it myself. I really like the look of those vintage go karts but unfortunately I don’t have access to a pipe bending machine so i can’t build one with those beautifully curved pipes. I’ll probably have to build it from 1“x2“ box sect with no curves.

 

[G.W]

Those are sick engines! I love old flathead engines, I've got a handful, but they are only single cylinder . What make an model is that engine?

 

[Denny]

Build a kart of you’re dreams. That beast will make it move.

 

[u500771]

Those are sick engines! I love old flathead engines, I've got a handful, but they are only single cylinder . What make an model is that engine?

Its a MAG 2055 ( MAG stands for motosacoche, an engine and motorcycle manufacturer in geneva, switzerland). They where mostly used in Einachsschlepper (basically looks like the front end of a tractor with some handlebars behind it. they are mostly used on small farms or in the mountains where normal tractors can’t get for mowing grass or plowing snow). Unfortunately i don’t think you can get them in the US and sending one over would probably cost a fortune because those things are pretty heavy because of the cast iron block (150 pounds approximately).

 

[u500771]

So today I started to take out the crankshaft from the stationary version engine (I’m going to call that one engine 2 and the other one engine 1). It was a lot harder than i thought because you had to pull of the gear for the camshaft which was held on by a press fit ring. The press fit ring had 2 holes for some m4 bolts (they are about .16 inch in diamete) but the bolts kept bending and cracking when i tried to pull it off with a puller. I had to pry the ring back about 0.4 inch which took about 4 hours. After that everything went smoothly and the crankshaft was out in no time. The plan is to use the crankshaft, crankshaft bearing plate, flywheel, fan housing, camshaftgear cover and the oil pan from engine 2 and the engine block with the valves and everything as well as the cylinder head and pistons from engine 1. I piled the parts i need for my engine on a little wooden palett. So i started to dismantle engine 1. the pistons and almost everything else came out pretty smooth and fast. Then it was the flywheels turn. It is secured to the crankshaft with a 41mm (1.6 inch) nut. So i secured one side of the crankshaft in place so it doesn’t turn and tried to undothe nut with my largest adjustable wrench but without success. Because the flywheel curves inward (almost like a dish) the wrench kept slipping off. I went to my granddad and looked in his garage (he was a trucker most if his live and still has a lot of those big tools he used on his trucks) but the biggest socket he had was 36mm (1/5 inch smaller than i need). Has anyone an idea how i could maybe loosen this nut without buy a new tool that costs 50-100$ and would only be used to work on this specific nut in this specific engine?

 

[Denny]

Sorry, I can’t be of help. What about a friend having one? As for the ring when you go to put it back together heat it up with a torch and just slide it on when hot and then tap it down gently.

 

[u500771]

Sorry, I can’t be of help. What about a friend having one? As for the ring when you go to put it back together heat it up with a torch and just slide it on when hot and then tap it down gently.

Thats what i have done after 3 hours of just blindly trying to pry it of xD. Unfortunately he only has sockets to about 20mm or 4/5 of an inch.

 

[Denny]

Hate to say it but you’re going to have to bite the bullet and buy a socket. After all you will need it to properly torque the nut back on.

 

[Bansil]

do you have a welder? if so cut 6pc of steel, weld it together to make a "socket" then weld a bar across it and hit said bar with a hammer
@u500771

 

[ezcome-ezgo]

Do you even know which direction to turn that nut?

 

[u500771]

Do you even know which direction to turn that nut?

Well, it’s a normal nut so counter clockwise i‘d say

 

[u500771]

Since my last post I’ve ordered the right wrench but they didn’t have it in stock so i‘m still waiting that it arrive. In the mean time i started to visualize some ideas in my CAD program of how the go kart could look like. I really like the idea of putting the engine in the front (makes also sense concerning the balance). Because the engine fits better lengthwise i‘m probably going to attach a 90 degree transmission.

 

[Denny]

I hope you make it longer than that.

 

[G.W]

Since my last post I’ve ordered the right wrench but they didn’t have it in stock so i‘m still waiting that it arrive. In the mean time i started to visualize some ideas in my CAD program of how the go kart could look like. I really like the idea of putting the engine in the front (makes also sense concerning the balance). Because the engine fits better lengthwise i‘m probably going to attach a 90 degree transmission.View attachment 141655View attachment 141654

Rat rod wagon inspired?

 

[u500771]

Rat rod wagon inspired?

Yess but only because i‘ve found a pretty affordable 90 degree transmission

 

[Denny]

Yess but only because i‘ve found a pretty affordable 90 degree transmission

But will it be strong enough? Handle the shock loads?

 

[u500771]

But will it be strong enough? Handle the shock loads?

its rated for 12hp and 190ish N/m of torque sl probably yes. the only thing that concerns me is the max rpm of 540 xD

 

[u500771]

But will it be strong enough? Handle the shock loads?

just looked it up, it seems like cars and cameras used the same gearbox