Briggs Flathead Mods and aftermarket carb

[panchothedog]

RLS Underground. Please don't include Bultaco on the list of " turd " machines.
They were Killer bikes in their day. Although, like you mentioned, they weren't around for that long. But a lot of others have fallen by the wayside. Most of them British, many of them in business for decades before Japan dominated the motorcycle market place.

 

[Scrambler]

Karting much like dirtbikes had a boom era... there are dirtbikes (many of them turds) that were made by companies that did well for a short time and vanished into the dusty archives.

Chaparral (better know for snowmobiles)
Bultaco
Hodaka
Rupp (they rode the dirtbike, minibike, and kart waves)
just to name a few.

The short of it is the fact you can't find anything means it was a smaller company that may or may not have done well, but disappeared as quickly as the rose up. There's many things that were lost to the pre-internet dust because they just didn't leave a significant footprint of remeberence

I am familiar with rupp, my uncle had a red rupp mini chopper, and it looked pretty darn good. I have to say, i have seen some rupp catalogs and other pictures and the kart i have looks very simmiler with only some minor differences. I think it was a smaller company and the nameplate i belive said made in Dearborn Mi

 

[Scrambler]

You can't power a fuel pump off of the pulse from the valve cover, because being a flathead it has no valve cover. Maybe there's a port somewhere that you can tap
into. I'm not very familiar with that engine. Also I am completely wrong about suggesting a torque converter. Being a dual engine kart it obviously isn't a live axle, which is what is needed to run a torque converter. As many have suggested, figure out what you have before you start cutting it up. Two 2 strokes powering it
would be an absolute blast.

Accually it does, here is a picture for reference i was thinking of running a line from the black connector here on the valve cover to run the pump.

 

[Thepartsguy]

You can't power a fuel pump off of the pulse from the valve cover, because being a flathead it has no valve cover. Maybe there's a port somewhere that you can tap
into. I'm not very familiar with that engine. Also I am completely wrong about suggesting a torque converter. Being a dual engine kart it obviously isn't a live axle, which is what is needed to run a torque converter. As many have suggested, figure out what you have before you start cutting it up. Two 2 strokes powering it
would be an absolute blast.

It has a breather cover over The valve spring chamber. Go to YouTube and type smittys garage vm22 swap big hoss minibike. He directly runs the pulse off the briggs valve cover.

 

[Rat]

You can't power a fuel pump off of the pulse from the valve cover, because being a flathead it has no valve cover.

Actually they do amigo, it's not a rockerbox cover on top of the block No... but there is in fact a valve cover on the side of the block with a phenolic reed over the valve stems and springs right below the ports

Maybe there's a port somewhere that you can tap
into. I'm not very familiar with that engine. Also I am completely wrong about suggesting a torque converter. Being a dual engine kart it obviously isn't a live axle, which is what is needed to run a torque converter.

Not entirely true, but it is a total PITA because you have to use an adapter deck (or cut and weld) to raise the engine and move it over. I'm not sure if a jackshaft motor mount plate would help any but I DO KNOW that the majority don't have the 4bolt case cover needed to use a TC backplate, but they do exsist and can be gotten.



I know altering the spacing to put the drive sprocket (countergear) outboard of the driven instead over where it is intended to be is not a realistic option.

The torque loading and leverage gained on the shaft by having it so far outboard will bust the common aluminum backplate and can twist most steel ones. It can also cause the shaft to fatigue and snap off.

RLS Underground. Please don't include Bultaco on the list of " turd " machines.

I wasn't specifically targeting turds... but there was a lot of them.

They were Killer bikes in their day. Although, like you mentioned, they weren't around for that long. But a lot of others have fallen by the wayside. Most of them British, many of them in business for decades before Japan dominated the motorcycle market place.

I had a 1970 Chaparral ST80, which was powered by an 80cc Fuji 2cycle with a 4speed box. It was classed as a "Middle wweight"meaning too small to be a dirtbike, but too big to be a minibike... it was fun to restore and then ride but then it got stolen.

 

[Denny]

That kart looks like a Rob Ron or a Rupp. Need more pictures. Your brake flaps are upside down.

 

[Rat]

I am familiar with rupp, my uncle had a red rupp mini chopper, and it looked pretty darn good. I have to say, i have seen some rupp catalogs and other pictures and the kart i have looks very simmiler with only some minor differences. I think it was a smaller company and the nameplate i belive said made in Dearborn Mi

Rupp is one of the most documented and well known ones that didn't fall rapidly into the unknown.

Your kart look like this McCullough R1 by chance?

You should take a look under the rear and look for cut or broken off welds on the left side. There was a kart that ran twin B&S 5hp engines and the left used a half shaft under/behind the left one to put power to the wheel.

It is possible the wheels are not original, but that kart was powered independently at each wheel.

 

[Thepartsguy]

I know altering the spacing to put the drive sprocket (countergear) outboard of the driven instead over where it is intended to be is not a realistic option.

If he can get some square holes in a plate and some cap-head square base screws he can move the one engine over very very easy. Other then that no not easy.

 

[Denny]

Not a McCollough.

 

[Thepartsguy]

Doesn’t matter what it is to me really if he wants a gokart to run the snot out of and modify that’s not the one in my opinion.

Could it be a robron after mr. Stanton bought out rupp??

He could EASILY keep the engine and trade the roller for something most likely equally as cool.

 

[Denny]

Robron is what I am thinking. I’m also thinking the rear of the kart has been modified.

 

[Scrambler]

Nope. Not a rupp or a robron unfourtunatly. Cant get pics today gonna have to wait until later this week. The thing is i have no idea how it was run with dual engines becuase the axle is just a threaded rod thats like built in to the frame.

 

[Scrambler]

Found these (ignore the garden hose stickers)

 

[Thepartsguy]

Nope. Not a rupp or a robron unfourtunatly. Cant get pics today gonna have to wait until later this week. The thing is i have no idea how it was run with dual engines becuase the axle is just a threaded rod thats like built in to the frame.

Is there bearings in the side of each back wheel? Round stock is all that is used on yardkarts Back in the 70’s.. Each wheel pushed onto the round stock and sometimes were ONLY held on to the axle with one small cotterpin. That’s called open wheel. The sprocket mounts directly to the rim to spin it. So a chain to each wheel.

 

[Thepartsguy]

Someone started to build a duel engine kart welded down the mount and simply never finished.. unless it was duel engine converted to single engine open wheel. It’s a yardkart conversion just like mine. That second engine mount runs to nothing.

 

[Scrambler]

I dont think the axle spins, there is a sprocket welded to the rim hub.

 

[Scrambler]

Someone started to build a duel engine kart welded down the mount and simply never finished.. unless it was duel engine converted to single engine open wheel. It’s a yardkart conversion just like mine. That second engine mount runs to nothing.

That sounds about right on

 

[Thepartsguy]

That sounds about right on

The good news is the frame already has the second engine mount! AND yours is already single seat. I had to convert mine. So just finish it OR trade it to someone for somthing cool.

I would personally wait a week for parts to arrive and just do it the simple way and find another Briggs. It’s VERY easy to convert them.. The second mount and center steering/seat conversion AlREADY being done would just make my job easier.

 

[Scrambler]

So ur saying that its possible to run dual briggs engines? I see ur making a live axle with pillow blocks there?

 

[Thepartsguy]

The thing is i have no idea how it was run with dual engines becuase the axle is just a threaded rod thats like built in to the frame.

Finish up by swapping in a standard live axle. Then two sprockets fixed to the axle spin both tires also fixed to the axle. The live axle allows you to put your sprocket ANYWHERE you please. So when using two Briggs you mount them the same way and run one sprocket in the middle.