Need help

[Desha D]

So this go kart originally had a 150cc engine with reverse... can anyone tell me how this 9hp 270cc engine would be better for this? I dont understand the difference between the motors and one using gear drive. While the 270cc is using a 40 series torque converter.

 

[MacGyvers Workshop]

If I may offer my humble input...

First;
if you use the 9HP motor and torque converter setup, you will lose the reverse ability (obviously) unless you do some really crafty "MacGyver" type fabrication back there. I think that the original motor actually uses a similar torque converter setup, its just enclosed inside the case with the addition of a reverse gear. It works great, just limited in power handling capability.

Second;
It will go like stink with that big motor on it. The existing brakes should hold up (I couldn't tell if it had front brakes or not, but either way you will have some fabrication work to do.

Looks like it will be a great project! Best of luck, and I am sure everyone here on the forum will be happy to offer any build advice

 

[itsid]

well the 9hp would NOT be better at all!
it has slightly more torque,
less HP, less rpm to get you to speed and worst of all:
you need to reweld a whole new motormount
definitely replace the rear axle sprocket for a MUCH larger one (otherwise you'll just not move)

and to add reverse you will have to invest in a reverse gearbox
and add a mount for that as well (130 bucks 'ish)
https://www.amazon.com/AlveyTech-Reverse-Transmission-Go-Karts-Converters/dp/B07CJY4DWH
(as an example.. make sure to buy the matching shaft diameter and sprocket version for your TC and rear sprocket.)
or this (5/8" shaft though)
https://www.gokartsupply.com/gearbox.htm

the good news is that gearbox replaces that stupid series 40 backplate
that is not going to make you very happy anyways..
it eats belts and costs hp (at best you now have a 6horse setup)

the gy6 engine you had originally on the kart does not use gear drive exclusively..
it too has a CVT (variable belt pulley system just like a Torque Converter)
it's internal pre and post cvt gearing however and it's much higher rpms
make it a superior vehicle mover compared to the industrial engine the gx270 is

So if you could.. repair the original engine (it's often the best chance you have)
or buy a gy6 replacement engine of the same size and style

an engine swap against an industrial engine is IMHO a stupid idea
and only to be performed if you have a very good reason for that.
lots of welding and fabrication to do...
and if not careful you can run into a space problem in the end
hitting the engine against the chassis at the end of suspension travel or something.


'sid

 

[Desha D]

You guys dont think that 9hp will push that go kart? I knew I was losing reverse. The old motor is shot to crap, and I'm completely redoing this I hope this 9hp will work for what I'm doing. It does have front brakes

---------- Post added at 02:44 PM ---------- Previous post was at 02:44 PM ----------

I will try to post more pics of it

Here is two pics redone frame

 

[mckutzy]

You have to turn the phone to landscape to get the right orientation... otherwise they are on side...

 

[MacGyvers Workshop]

What matters in the end is what you want to do with your project. If you want to use the big Briggs motor, then by all means do it, and make it work! Mine was a regular kids go kart, strengthened and modified to use a 600cc sport bike engine. No reverse, and is the textbook definition of insanity! I didn't build it that way because it made sense, I built it that way because I wanted to embrace the challenge.

 

[itsid]

well sureely 9horses are enough to move the kart around..
the engine is just not able to do so at nearly the same speed as it moved with the original engine.

Sure you can add another few hundred bucks and mod the engine to propell the kart to the same speed
but by then you added the same amount of money you would've paid for the original engine (or more)
and added four to six times the amount of work.

IMHO pointless..
but the decision is yours to make..
if you WANT an industrial engine, go ahead..
if you want just the kart to run again..
go and buy a gy6 instead it's certainly the better option

'sid

 

[Desha D]

So far things are going, that 9hp has done pretty well I'm pushing near 40mph. 60 tooth sprocket, 20inch tire and rim with 12 tooth sprocket on clutch. So far I'm happy but waiting to see how long it will last

 

[Desha D]

Max speed 47mph opened wide up on flat road.

 

[950speed]

I’m sure it will last a good while, good to hear it works