Briggs Flathead Mods and aftermarket carb

[Scrambler]

Unfortunately i dont have a welder otherwise i would have had a dual engine kart made by now LOL. My plans are to just mod the engine i have. I know it may not be the perfect kart to hot rod, or engine, but this is what i got and im just looking to make the most of it. In a couple years I probably will just get a 2 stroke snowmobile engine and throw it on a better frame.

 

[Rat]

Or if you got big balls, or a shortage if sense... you do a double open wheel

Prepare Your Last Will And Testament Before You Buy This Twin-Engine Gokart - Jalopnik

How much power does the average gokart have? You know, like the ones you buy at the big box stores for $599 or whatever and your kids you have it wrecked within the space of the afternoon. Usually no more than a couple, right? The best of them have a 5 horse Briggs. This one has two, count ‘em...

jalopnik.com

 

[Thepartsguy]

Or if you got big balls, or a shortage if sense... you do a double open wheel

Prepare Your Last Will And Testament Before You Buy This Twin-Engine Gokart - Jalopnik

How much power does the average gokart have? You know, like the ones you buy at the big box stores for $599 or whatever and your kids you have it wrecked within the space of the afternoon. Usually no more than a couple, right? The best of them have a 5 horse Briggs. This one has two, count ‘em...

jalopnik.com

That’s wild. Looks like it might be easier than/cheaper then a live axle swap!

 

[Scrambler]

Now this looks like something I actually could accomplish, just don't know where to start on building a jack shaft like that

 

[Thepartsguy]

Unfortunately i dont have a welder otherwise i would have had a dual engine kart made by now

Now this looks like something I actually could accomplish, just don't know where to start on building a jack shaft like that

Ask just about anyone in your area for help with welding.

If I was tromping through the muck on the farm and you drive by seen me welding on a tractor and pulled in and asked I would help you for like $20

2 four pound spools of welding wire is $20 so if you gave me a $20 and I helped you out with the jackshaft I’d spend the $20 you gave me on wire. I’d have 16lbs of wire and you would of payed for half of it..

 

[Scrambler]

I just may do that mabey this summer. Any idea what the components of this jackshaft are or how I could make something similar mabey withe pillow bearings? Just seems a lot easier than making a live axle, I have lots of chain laying around and sprockets are pretty cheap

 

[Thepartsguy]

I just may do that mabey this summer. Any idea what the components of this jackshaft are or how I could make something similar mabey withe pillow bearings? Just seems a lot easier than making a live axle, I have lots of chain laying around and sprockets are pretty cheap

To make that I would use

2 pillow blocks
axle itself 1” whatever length
2 10 toothe or 12 tooth c-sprockets for a 1” axle
2 keys that lock the c-sprocket to the axle.
2 plates to bolt down the pillow blocks that would need welded to the frame.

Still that would be extremely simple and I know what way to go if I ever find a cheap open wheel kart now!

 

[Scrambler]

Thanks! I appreciate it, when I get to building one some time I'll let you know.

 

[Rat]

Ask just about anyone in your area for help with welding.

If I was tromping through the muck on the farm and you drive by seen me welding on a tractor and pulled in and asked I would help you for like $20

Lmao a 2lb runs $23 here, and a 10lb is $67 there's not getting other sized spools without making a day trip of it.

 

[Thepartsguy]

Lmao a 2lb runs $23 here, and a 10lb is $67 there's not getting other sized spools without making a day trip of it.

Just awhile ago I picked up 4 2lb spools for like $23 shipped straight to my door.

The ebay wire seems to burn through gokart tubing about no different then the expensive stuff they hock off on people at the big box store.

I’m looking now it seems to have gotten a bit more expensive.

 

[Rat]

Just awhile ago I picked up 4 2lb spools for like $23 shipped straight to my door.

The ebay wire seems to burn through gokart tubing about no different then the expensive stuff they hock off on people at the big box store.

I’m looking now it seems to have gotten a bit more expensive. View attachment 145553

I get E71T-GS .035 Forney wire locally, and I don’t blow through too much of anything usually. You might want to practice more or clean your machine, idk.
I've welded 18ga sheet with my Horrid Fright Chicago Electric rig and had more issues with it puckering than blowing out.

I've been abusing that thing religiously since I got it about 5yrs ago and only recently had some trouble with it, thankfully it was just a faulty (cooked) toggle. Took more time to open the cabinet and diagnose than it took to correct the problem, cleaned it out while it was open.

I have blown out some Chromoly tubes, but they were pretty thin junk.

I've used "Blue Demon" (ebay) and Hobart (Lowes) as well as some bargain wire from ebay and truth be told I've noticed no significant difference beyond the amount of flux ash generated. I do know I had more blow outs with .030 wire though I was horribly out of practice at that point.

My welds still ain't always Purdy, but you won't break 'em and you'll play hell to cut through 'em.

 

[ezcome-ezgo]

Clutch Mount with Jackshaft | 03191

www.bmikarts.com

 

[Scrambler]

does anyone know the measurements between the carb and exhaust bolt threads?

 

[Scrambler]

reason i ask is because i cant get to the kart in storage right now to measure it and id like to order a carb.

 

[Thepartsguy]

reason i ask is because i cant get to the kart in storage right now to measure it and id like to order a carb.

You don’t just order a carburetor and bolt it on/go you need to weld together an intake. You can buy one for $50+ And then a cheap $20 carb.

your other options are a tecumseh intake and that‘s just a flop entirely

weld together an intake

Or your best option yet use that tank carburetor!

 

[Scrambler]

I have a Tecumseh intake and bowl carb, i think the carb is junk though i had it on the engine before and it sucked.

 

[Rat]

reason i ask is because i cant get to the kart in storage right now to measure it and id like to order a carb.

Right about 38mm iirc, but unlike you all my stuff is right downstairs in the garage and I can get you exact measurements

 

[Rat]

Your exact stud spacing measurements should be 35mm Intake, 40mm exhaust.

Why metric measurements on an old American made engine you might ask. It is as simple 99% of the measurements you will find are going to be metric not ASE/Imperial so I'm not going to give you some asinine measurements you likely wont be able to find.

As you've been told already, to swap to a non stock carb you must first completely remove all the governor hardware and make an intake manifold.
A PZ19 is a perfect fit but will very likely run too rich and need to be jetted down a couple sizes on the pilot and main both, I know this because I put a PZ19 from a CRF70 on a 5hp B&S already and it was to my surprise too rich. It ran ok but would load up and stall if left idling for too long

 

[Scrambler]

Ok thanks for the measurements, would a 3hp flywheel be a safe replacement for the 5hp flywheel? If not where can i find a cast aluminum one.

 

[Scrambler]

I dont think its safe to remove the governor until i have a flywheel that can withstand the extra rpm.