Beta VC 625 install in 87 G2

roadtech

I am posting about the changing of engines in a 87 Yamaha G2. This will be more about results instead of “how to”. I am not a writer but I think this is a great engine (Vegas Carts 625cc).

This engine was sold as a beta stage install and it is. I just wanted to improve on the very tired engine in the cart. I lived close enough to pick the engine up at the VC location (las vegas, NV). The engine and assorted parts came in 2 boxes. I also picked up a new clutch for the Differential. The only instructions were a wiring diagram for the new ignition switch.

The mounting Hardware was a couple specially machined plates to attached the motor to the frame. The install required the removal of old plate and motor mounts. In my install the rear plate required the mounting hole needed to be enlarged a little. The plates installed and the engine fit like a glove. The engine came with a pull start setup, This setup needed to be removed for the install.

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roadtech

I forgot to mention that a shaft at the top front of the differential need to be remove so the engine will fit.

I removed all the electrical of the old engine none applied to the new engine. Hooked up the fuel. Filled the engine with oil, no indication of how much oil was required. Diagram on engine indicates where to fill to. Took just a tad under 2 qt's. Fired it right up and idled fine.

First test spin and the power was unbelievable. The clutch was grabby at start (an attempt to raise rpm over idle the cart would launch). This improved after a few starts. Parked cart for the night.

Next day I tried a longer test run and the engine stalled and would not start. No fuel. Old pump gave out. Decided to adapt an electric pump (Mister Gasket 42S) 2 – 3.5 psi. waited a couple days for pump, hooked up and the engine fired right up. After the engine would warm up it would not idle properly and ran poorly. After trial and error determined that the 3.5 psi was too much for the float and needle after some research I found an easy fix. I added a 1/4” x 1/8 pipe fitting to the fuel tank for a return line. I placed a “T” in the feed line to the carb and pointed it to the fuel tank. This allow the over pressure to return to the tank. The engine runs great and Idles properly.

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roadtech

Since I am able to drive, I added gauges (oil pressure,volt meter, fuel level). I ordered a gps speedometer. To my surprise it registered 36 mph before the engine rev limit cut it off. I set the throttle limit screw to prevent the rev limit from stopping the engine and still see 36 mph. This sound high so I down loaded an app for my Iphone and it confirmed. I checked the Differential and The input shaft turns a little over 5 turns to one turn of the rear wheel. Not sure what that relates to in ratio. I have ordered a Tach to confirm rpm. Hopefully I can get betters answers on the speed. This is a basic Yamaha G2 with standard tires and no lift kit. Not sure what gears are in the Differential.

Shepard

I run an 87 G2 with 20x8x10 tires -- 780 comet clutch -- VC460 -- standard ratio 13 to 1 and achieve 24-25 mph at 4000 rpm. You can't get an accurate count for the ratio spinning one wheel and the other locked. Put the cart on the ground - mark your tire and mark your secondary clutch and move it one rev on the wheel and count how many times your 2nd clutch turns. Have someone help if needed.
The only gears available now are 8 to 1 ratio. There hasn't been 6 to 1 gears for the Yamaha G2 in so long no body can remember. 8 to 1 gear sets are slowly disappearing because of the age of the machine.
I can say 36 mph sounds a little high for 18 inch wheels if there stock. This engine has a 4000 rpm rev limiter -- have you disconnected it? From my personal experience 20 - maybe 21 at 4000 rpm with my 18x8x8 original rubber.

Rooster59

Can you post a photo of how your accelerator cable hooks up to the carb lever?

Sounds like you have a nice finished project.

Sent from my Moto G (4) using Tapatalk

Shepard

xxx

ironmonkey17

Nice, 36mph on stock tires.. impressive..

Rooster59

Thanks Shep. I was actually looking for the OP's cable to carb setup on the 625. tireguy did quite an elaborate linkage to get linear results. The OP didn't mention any issues so I was wondering if it was EZGO TXT related or related to the linkage provided by VC on the 625 in general.

I was staring at the bellcrank setup on my 96 TXT from the axle governor to carb and should be able to salvage quite a bit to arrange a linkage that won't require a longer accelerator cable and give linear feel.

roadtech

I removed all of the diff governor cable, using the main cable from the gas pedal I cut end of the cable so I could thread it through the cable clamp on the throttle lever (red). The lever has a little play at the start so I clamped the cable with about an 1/8" of play before the throttle level in-gauges. I am mindful of how hard I push the gas pedal and don't seem to have any problems. (just regular driving on the street)

The cable in my finger is for the choke, when cold (below 60) I manually set the choke and after starting I use the original choke cable to turn the choke off. The engine starts well with out choke , but the choke will get it started quicker.

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Rooster59

Thanks roadtech. That helps alot. The engine in an EZGO gets mounted 180 degrees from the way yours is, cyl head to the rear. My throttle would have to come across from the clutch to the throttle lever. A bell crank system using the stock EZGO linkage should work fine with what is provided.

That plastic choke lever is a weird one. Might take some serious thought (and thinking fluid) to come up with a true push pull choke system. Getting a longer choke cable looks like the easy part.