Briggs 8hp advice

#1
My uncle has a briggs 8 horse that he might sell to me, but I have a few questions.

Question one, is there anything I should know about these engines throttle hookups beforehand (are there remote operation throttle plates available if one isn't on the engine)?

Question 2 do these have a 3/4" or 1" shaft (I'm thinking 1" but I'm not sure)?

Question 3, If it is a 1" shaft, should I keep using the 30 series and use a new driver, or should I put the 30 series on my drifter, and run a 40 series. I'd think the 40 series would be more reliable, but would it be worth the added price?

And question 4, do 8 horse briggs's have a similar mounting pattern to a predator 212 (the current engine, which is straining a little bit). The only measurement I'm worried about is the width. The slots are long enough (2 1/2" ish).
 
#3
So, since the 8hp would be wider, could I make a spacer that sits between the engine and the frame out of 5x2 rectangular tubing that has the right slots on top for the engine and on the bottom for the frame? Or would that be a bad idea? But I'll get the mounting dimensions for the frame.

I do remember, somewhere, seeing one of these karts with a 9 horse on it, but I could be mistaken.
 
#4
Welcome to the OldMiniBikes J.S.@SMS...!!!

Good questions. I think with the 8 hp, it's probably the height of the motor that would be the main concern...in relation to the space available in your frame.

Keep us posted, and have fun.
 
#7
Thanks for the replies. Sorry, I should have been more specific about what it'll be going in. I have a Ken Bar Streaker DD9 go kart (a big and very heavy go kart), that's putting a slight strain on the predator 212 that's on it (even with a 30 series 7" driven and 6.6:1 gearing). It is a nice kart, just heavy, and it fits me quite nicely considering I'm 6' 2" and a half. And when I was putting the predator on it I checked to see if there was enough height to fit a motorcycle trans under it, using a Yamaha Warrior 350 case for the height base (12" extra if I remeber right). It cleared by a half a foot. Here's a pic of the kart. It's got 22" knobbies and a differential axle from factory. I really need a new pic, this one is from last summer, when it still had a tecumseh on it (I'm in the process of rebuilding the tecumseh). And that was a true comet, but it was pitted and wore out.
gokart.jpg
 

old shed finds

Well-Known Member
#8
My best advice is fully rebuild your Tecumseh up bore with new piston rings ect.

With the pic now your eng plate will be too small to fit a BB mount pattern.or custom build one .and that rear seat back tube might come way close to the cylinder head of the uncles 8hp...
Then fuel tank mount location?
Let me know what you think?
 

old shed finds

Well-Known Member
#9
So, since the 8hp would be wider, could I make a spacer that sits between the engine and the frame out of 5x2 rectangular tubing that has the right slots on top for the engine and on the bottom for the frame? Or would that be a bad idea? But I'll get the mounting dimensions for the frame.

I do remember, somewhere, seeing one of these karts with a 9 horse on it, but I could be mistaken.
Was the kart purple? Me and son did a 8hp Tecumseh on a purpleYurf Dog kart.but small wheel model live axle on sharp turn matting the throttle the torque would flip it on its side scary power.....
 
#10
I honed the Tecumsehs bore a bit to give it a nice crosshatch, but I wanted to keep the original piston. The engine ran fine when I got it, however it never put out enough power for this thing. And it started burning oil and smoking a bit. When it's done it'll be going on my Manco 415-10.
If you mean it'll hit the headrest, that can come off since it's not attached to the seat, and is purely aesthetic (My head doesn't bend back that far).
And for the fuel tank mount, it has some sort of battery box to the right of the engine (I'll post a pic) that I think might be a good spot.
As far as I know it's the original color, and this thing doesn't have enough torque with the big tires (I'd replace them, but they're in good condition and new ones are just too expensive). And one thing I love about this kart is the turning. Ken Bar thought ahead on this thing, all the big streakers I've seen have the differential axle.

And I remembered where I found the 9hp on one of these.
http://buggymasters.com/forum/showthread.php?t=265

Here's the battery box thing. Again with the old pics, I really need to get some new ones, but this is from before I cleaned it up last summer. Or no, this is from summer 2018.
IMG_1888.JPG
 

old shed finds

Well-Known Member
#11
Sorry for late reply..
Anything is possible. Measure and build the engine mount plate.
When installed the kart will have lots of power. Just #1 rule always hook up and test kill switch.....
Ebay has choices of comet copy clutch 30 or 40 cheap price.... Keep in touch.
 

Addicted 2 Minis

Well-Known Member
#12
I don't know what your budget is but I would get a 301cc 8HP Predator ($235), almost twice the torque (15 ft lbs ) than that of your 212 (8 ft lbs), the mounting pattern is about an inch longer and wider but the over all size would be less than a flathead Briggs. Remember, when adding more power, something somewhere else may become a problem (clutch, differential, etc).
 
#13
I was thinking about getting a 301, and adding a gx270 flywheel, alternator and starter, for electric start and headlights. But the briggs is more period correct. And I might just trade him a manco 415-10 frame (I picked up with two others and a new predator for $300) for it, as opposed to $235 for a predator. But the predator isn't out of the budget (I've already spend like $800 getting the kart to this point, may as well add some more) and it would be new, so no surprises like junk internals.
 
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