G1 Clone Build: Vegas Carts 440

[slonomo]

If I was going to do the carb swap again, I would definitely use a genuine Mikuni carb and good quality corresponding parts. The payoff would be a super clean and low idle, and better throttle response and power at higher rpm.

If anyone is curious, for less than $200 you should be able to do the Mikuni swap. Here's what I found....

Mikuni VM28 $85
Mikuni choke conversion kit $12
Billet adapter $42
Adapter hose $5
Uni Filter $22

Total $166 plus tax and/or shipping

Jets R Us sells the jets if you need them
JRPW Racing sells the carb adapter and hose
Carb, choke kit, and air filter can be found on Ebay

[slonomo]

Here's a video of the test run with the "32" uh hem...."28" mmm carb. This was an aftermarket cheap $30 carb, listed on ebay for a GY6 go kart. Not the best quality carb. But, it did run pretty good. It was a little lean on the top end. I couldn't find jets to match it, seems like an oddball.

When I ordered the carb the listing said "32mm". When I got it, it was clear that it was not a 32mm. After measuring the throat/venturi as best as I could, it looked more like a 28mm. Just wanted to clear that up.

Also, I in the video I was focusing on the tach to see my increase in rpm, but the tach obviously was loose on the plug wire. That engine had a really small diameter wire and the pickup clamp never really fit all that well. So the needle jumps around a bit. But you get the idea. This is a built 460 engine so it would rev to 7000 rpm with that carb. I think my max speed with that setup was 42 mph? I'd have to go back through my threads to confirm that.

This is just to prove that you can literally just bolt on a cheap carb and it will run and drive. If you use a good brand carb, like Mikuni, you can easily tune the jets to get the a/f mix right. This particular carb was never tuned and I drove it around for months, ran really good.

Here's a pic of a similar carb. Its the one with the electric enrichment "choke" and accelerator pump.

https://www.youtube.com/watch?v=IEplO1vwB1g

[slonomo]

Here is my thread about the carb upgrade.

https://www.buggiesgonewild.com/showthread.php?t=97273

In the end, my G1 cart didn't have room for the carb and filter due to the frame upright being in the way. But I was getting super close with the jetting. I finally did get it starting and running good, with good power, but I just couldn't get an air filter on it without making crazy bends in a rubber intake hose and having kinks in the intake.

So, my recommendation?

If you want more power and speed out of your "built" clone engine, definitely invest good money in a genuine Mikuni or equivalent and do it right. Just make sure you have the room in the engine compartment. The difference in performance and quality of idle and throttle feel is worth the investment! Also keep in mind that tuning the carb is a little tricky and be prepared for lots of reading and video watching to learn what to do.

[slonomo]

I was looking for an assembly tutorial video on the VC460 back in the day, never did find one. But now Red Beard's Garage has one from last year. It's actually a well made video and he does a great job breaking down the assembly process, seems to cover all bases. Good video to watch. I figured this video would be nearly the same for other clone engine builds and is perfect for the small engine novice.

It appears in the video that he is using a Mikuni carb. Wonder what size? He doesn't specify.

https://www.youtube.com/watch?v=FKdlwZrYAeo

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