G-29 speed increase help

[11yammy]

First time posting so please be patient with me. I have a 2011 Yamaha G-29 Gas golf cart that I bought from a golf course. I brought it home and used a GPS to check my speed, the GPS only read 9 MPH. I adjusted the 10mm nut on the govenor to were i have roughly 1/2 in left. I now read about 14mph on the cart which is close to the factory setting on my dads 02 gas Club Car. The only problem is that my cart backfires every once in a while and its embarrassing. I would like to take the cart up a few more mph but I am affraid to do so with the backfiring thats already taken place every so often when I let off the gas. please help?!?! how can I make it faster without spending a lot of money and not damaging my engine? Thanks in advance

[seoighs]

That backfiring is a common problem, and I had the same symptoms when I got my (2007) G29. It's often corrected by nothing more than cleaning the carb thoroughly and avoiding the use of ethanol-tainted gasoline.

You can get zero-E gas at stations which cater to operators of farm equipment, or take a 5 gal jerry can to your local airport and treat your buggy to a refreshing fix of 100 octane Avgas. I purchase ethanol free, 100 octane racing fuel at a road racing track where I pursue my 'other' hobby. My G29 runs like a top now.

For increased performance, there are things you can do to tinker (carefully) with the governor, and check the width of your drive belt and state of your clutches to ensure that they are within spec. You'll want to explore Don Plowman's site (or just search 'plowman's' here) to learn what's possible from a Yamaha. You've chosen a sound foundation. Where you take it is governed only by your imagination...and your budget.

'Hope this helps.

[SandbaggerYDRA]

Backfiring usually occurs due to a throttle that does not close completely at idle. The way golf carts are designed, there really isn't an "idle", so the idle speed screw on the carb should be adjusted to make sure the throttle closes completely.

A G29 cart, with the governor screw completely tightened, should reach a speed between 19 and 21 MPH on stock tires. If your speed is lower than that, it may indicate a worn drive belt and clutches. The original G29's were notorious for clutch problems. Give Don Plowman a call. He really knows how to dial in a G29's clutch system for maximum performance.

[NHRA_Racer]

Originally Posted by SandbaggerYDRA

Give Don Plowman a call. He really knows how to dial in a G29's clutch system for maximum performance.

I couldn't agree more with this statement. He has been helping me with an '07 G22 and has been absolutely phenomenal to work with.


http://www.plowmanscarts.com/

[11yammy]

I will give him a call, I have put in 93 octane ethanol free about a week ago but still no difference. I will leave the 100LL for my 172. I need all the fuel I can get for her.

[cgtech]

If i am chasing a backfire problem i follow this. First, check that there is some slack on the throttle cable at the carb when the pedal is NOT pressed. If that checks out, pull the carb and shine a flashlight into the opposite end to check the throttle blade (as shown in pics). If backfire is still present (maybe 1 in 20 carts still backfire), check valve lash. When fuel related, backfires in the intake airbox (muffled pop) result from lack of fuel, or lean mix. Backfire out exhaust (loud, tinny pop) are from too much fuel in the exhaust tract (carb not closed when pedal at rest), or rich fuel mix.

[11yammy]

Update, I contacted plowmans and have a clutch puller on its way,I decided to go with their upgraded kit for $375. Hopefully it will take speed up a considerable amount from where it was at 14mph. Im not sure I understand how everyone is getting 18mph out of thei governor being fully adjusted on a stock cart.

[dbmachine]

Many variables to get a bone stock cart to the 19 mph area with a simple tightening of the nut on the governor arm. Belt must be in good condition, clutch and clutch weights must be good, throttle cables adjusted properly, good air filtet etc. none the less im glad you went ahead and got the plowmans kit. Once you get it all installed and dialed in you wi be one happy camper smiling from ear to ear.

[Cas4621]

You will be happy with plowmans fur sure!!

[NHRA_Racer]

I just finished my Plowman's performance kit install and also replaced my primary clutch.

With the installation of the kit, the mods to the airbox (which is a little frightening), the carb adjustment and jetting, resetting the valves to .008 and locking down the governor, I am hitting 26 mph with my 2007 G-22. Don said he can get me to 30 mph with some throttle cable adjustments but with two younger kids, 26 mph is enough for me.

I am more excited with the expected low torque/hill climbing that I expect to have. If anyone has been to Bristol Dragway and camped at the top, you will know that you need a lot of low end torque to pull the junior dragsters up the hill!

And finally, Don was absolutely great to work with on the phone to complete all the work. This was money well spent and Don's help is really where the value comes from.