Powerful, portable, and efficient, the Yamaha EF2000iS Gas-Powered Portable Inverter delivers maximum electrical output without sacrificing portability. Thanks to its innovative inverter system, the generator is able to generate up to 2,000 watts of clean AC power. It can run up to 10.5 hours continuously without refueling and uses premium technologies to maximize fuel efficiency.
At a GlanceCombines powerful output with portabilityInverter system allows you to power delicate machineryFuel-efficient; can run for 12 hours without refuelingLightweight and easy to carryBacked by a 2-year warranty
Compact and ergonomic, the EF2000iS is easy to store and transport. View larger.
TwinTech technology allows you to hook up two units for added output. View larger.Powerful Inverter System Delivers Cleaner Electricity
The EF2000iS is built around an innovative inverter system, which is able to deliver higher-quality, cleaner electricity than competing generators. It produces energy in the form of pure sine waves, which are cleaner and more reliable than most commercial power sources.
In simpler terms, this means that you'll be able to confidently power delicate machinery without having to worry about the damage caused by unrefined energy. An electrical overload breaker is also included, to prevent generator damage in case of an unexpected overload.
Smart Technologies for Optimal Fuel Efficiency
The EF2000iS is exceptionally fuel efficient, able to run for up to 10.5 hours without refueling when in Economy mode. Its OHV engine runs reliably and dissipates heat efficiently, allowing for both a long life and optimal fuel consumption.
With its Smart Throttle Load feature, the generator is able to dynamically adjust engine speed depending on output, resulting in greater overall fuel efficiency. The generator also features an exclusive dual coil alternator stator, which lowers engine speed and reduces total fuel consumption.
Ergonomic, User-Friendly Design
Weighing 44 pounds, the generator is ultra-portable and features an easy-to-carry design. It has a convenient, centralized control panel, which allows you to easily access all of the generator's features at the push of a button. It also starts up responsively due to its auto-decompression system, which reduces compression and makes start-up less difficult.
For added convenience, the EF2000iS is able to recharge batteries with its 8A12V DC output, making it ideal for RV, auto, and boat owners. You can even hook up two EF2000iS units for added output, thanks to TwinTech technology. And you won't have to worry about engine damage due to low oil levels: an oil-watch warning system constantly monitors oil levels and lets you know when an oil change is needed.
Noise Reduction for Quiet Operation
The EF2000iS uses noise reduction technologies to ensure the quietest operation possible. Featuring a special sound-blocking design, the generator has noise-absorbing glass wool construction, which helps dampen noise even during heavy operation. Along with the EF2000iS' super-quiet muffler and vibration-isolating feet, it helps keep noise to a minimum.
The EF2000iS is backed by a two-year warranty.
What's in the Box
The EF2000iS has the EPA's longest engine emission life rating. View larger.
The EF2000iS recharges 12-volt batteries, making it ideal for boat, RV, and auto owners. View larger.
- Item Weight: 51 pounds
- Shipping Weight: 55 pounds
- Shipping: This item can only be shipped to the 48 contiguous states. We regret it cannot be shipped to APO/FPO, Hawaii, Alaska, or Puerto Rico.
- Shipping Advisory:: This item must be shipped separately from other items in your order. Additional shipping charges will not apply.
- ASIN: B002RWK9N2
- Item model number: EF2000iS
EF2000is review – high quality and very quiet
This is a very high quality unit, nicely designed. I chose it over the Honda Eu2000i because it has a fuel gage and is a hair lighter (2 pounds), and liked the styling better. Specs are so close it’s a tie… the Yamaha unit specs a bit quieter in “eco” throttle but the Honda specs a bit quieter at full power. Prior to this purchase I had bought a Honeywell inverter generator (a much less expensive Chinese-made knock-off) from Costco which I returned, because I was unimpressed with the Honeywell unit’s quality and noise level. While the price difference is major, you get what you pay for in this case. Anyone looking at the cheaper knock-offs should really consider that a 5db increase in noise level is a major difference, the way humans perceive it.
The most impressive thing about this unit is how quiet it is. Even at full engine speed you can stand about 6 feet away and have a normal conversation without raising your voice, or talk on a cell phone without undue distraction. It features an “eco” setting which tapers down the engine throttle and noise when full load isn’t required. At half-throttle or less, from about 6 feet away it is about half as loud and amazingly quiet. I used it to run a 50-amp 12v battery charger and at full charge level the charger only required the generator to operate at about half-speed, and when the charger tapered down the charge level to under 30-amps the generator became so quiet I literally forgot about it. It is MUCH quieter than my boat’s inboard diesel engine, and more efficient than running the main engine just to top off the batteries. I also used it to power a heavy duty 120v grinder and it had no problems supplying the needed power, even on electric motor start-up.
I got this mainly for charging our boat’s batteries at anchor but I also wanted the ability to run power tools. The lighter 1000-watt inverter generators could easily handle the charging application but not the more power-hungry tools. Having the extra power also means the eco-throttle will likely kick in earlier and the unit will operate quieter. The number-1 purchase criteria was “quiet” because I don’t want to be distracted by incessant noise or be a bad neighbor in anchorages. The Honeywell was not quiet enough in my opinion.
If generators are abused it will lead to regulations banning them, so an appeal to other boaters and to campers: Please don’t settle for “cheap”. Get a better quality inverter-generator unit that’s quieter so you minimize noise pollution in get-away places. (Leave your “contractors generator” at home!!!) Also, please be considerate of neighbors and limit running it to times/places you aren’t as likely to disturb others… and don’t leave your boat or campsite while it runs and runs. We all like our electric conveniences, but if you really need 120v power more or less constantly you should either stay home or get a dock/parking space where you can plug into “the grid”. It’s rude to disturb others who are trying to get away to find some peace and quiet.
Negative: The unit ships without engine oil, so you need to buy a quart of standard 4-stroke engine oil and fill it. You will also need a funnel, and a pan to catch excess oil. There is no dipstick; you need to fill to the level of the bottom of the filler hole until any more runs out. It uses less than 3/4 quart. I think they should have included the required amount of oil, and a plastic filler container with a spout, marked to show the proper amount of oil to use.
Update 2/22/2012: In general still very happy with the unit, but checking oil level is inconvenient (you need to open the case with several screws) and changing the oil is a messy operation involving rags and clean-up because there is no neat way to capture the waste oil or overflow directly into a container. I think the next generation of this product should improve on that design issue and provide a dip stick or oil level indicator that’s either externally accessible or located behind a quick-access panel.
Having owned this for almost 2 years now I would add the following:
1) I have found that it has enough power to run the charger AND the hot water heater’s 120v heating element at the same time. It is near-max (running full speed) but doesn’t light the overload light when doing that and the charger is in bulk phase. Nice when you’re in an anchorage for a few days and haven’t run the engine. Why run a 57hp diesel just to heat water and charge the house bank?
2) If I shut off the fuel and let the carburetor run dry before putting it away, it does not smell of gas with the fuel vent and fuel valve both closed. The maker advocates storing in a well ventilated area or garage, but odor from fumes is not a problem.
3) It’s also useful at home during power outages. I have a larger much louder 5500w contractors generator that plugs into a 12-circuit transfer switch wired by an electrician, but as a courtesy to neighbors I shut that off overnight. I can use this Yamaha unit with an extension cord to keep just the refrigerator running overnight and it stays in ‘eco mode’ so it practically purrs. Also the fuel burn rate is extremely low so it uses a fraction of what the larger generator would use.
Have had zero problems with this unit so far.
Super quiet and CARB compliant
This generator is super quiet and the engine runs really smoothly. It instantly changes it’s operating speed just as fast as I can move the speed switch on a 1850 watt hair dryer I used to test it. It doesn’t include oil and the angle of the oil fill hole is nearly horizontal, making it a little difficult to fill even with a funnel, but they did put a nice little drip tray right below the opening so it doesn’t go everywhere. The gas gauge is really nice. Made in Japan. Their competitor (Honda) has some nice videos on their website demonstrating the sound level of actual generators running and the equivalent size Honda generator is very close in noise level to this one. Yamaha should do the same but until then, check out the Honda website.
Yamaha says this is CARB compliant on their website so I’m not sure why Amazon says it isn’t. The label on the generator says it is a 3 on the 10 point California emission scale. Yamaha simply isn’t making a big deal of it like some others do I suppose. This is a new model as of summer 2009. The starter cord is really easy to pull – unlike any other engine I’ve ever started by hand.
This little gem arrived to me in perfect condition. Kudos to Amazon for their quick delivery time. The genny itself is bigger than the pictures let on, but for 2000watts, this isn’t bad at all. THESE UNITS DO NOT COME WITH OIL IN THEM. Go buy some 4 stroke 10w30 oil at home depot or lowes. Follow the instructions to put the oil in, fill it gas, and turn it on. The pull cord is very easy. Just practice a couple of times. You will love this generator, I promise. I will use it for my travel trailer for camping/fishing during the colder months.
Edit: I’ve had two EFYamaha 2000is generators since the beginning of Sept, 2010 and have mainly used them for camping. The first workout for both of these units was tailgating. I also have a cord that connects the 2 of them to make 4000 watts, more than enough to power your camper A/C (13,000-15,000btu) and everything else in the RV. However, it was colder on this outing and I didn’t need to use both hooked together yet. I did bring both of them though and I’m glad I did- here’s why:
The guy next to me brought his 6000watt Champion generator, which is construction grade, and told me he was sorry, but would be running it in the mornings. We were about 15 feet away from him. I said no problem, it couldn’t be that loud. He then turned it on for me so I could see. WOW! That thing was LOUD. I told him I brought a spare Yamaha inverter and he was welcome to use mine because I told him it would be much quieter. He came over and heard mine running and couldn’t believe it. The next morning we were both sleeping soundly, both of us running these awesome Yamaha units.
Here are some tips for those considering this generator:
1) Get some fuel stabilizer. This is not needed, but is nice because it stabilizes stagnant fuel that sits around during the winter months- or just longer periods where the generator is not in use. I use Stabil, and its sold here on Amazon. Put some in your gas can(s).
2) If a generator has been sitting around awhile, you need to run it periodically ( I will run mine about once a month for at least 10 minutes) to ‘exercise’ the unit. This will ensure that when you REALLY need it, it will start no problem.
3) Tie these units down when in transport. They tip over easy and if they do, when you start them up you will be greeted with a mess of white smoke (oil burn) until it burns off. Buy some ratchet tie downs. Bungee cords won’t cut it.
4) Realize the limitations of a 2000 watt generator. I don’t know how this got started, but someone somewhere said his 2000 watt genny was powering everything they needed without being specific. Then folks just assumed that they would get the same results. You HAVE to do a power audit for YOUR specific needs. What will you be powering? What is the main purpose of the unit? If you have an RV with a 15k A/C, one 2000watt will NOT power it on. Remember, air conditioners, microwaves, etc take pull a lot of AMPS to cycle on. Once they are on, the AMPS are reduced during the rest of the run time. The trick is, what will power these appliances THROUGH the higher amperage cycle? Thats why I bought 2 of them.
5) Buy a cable lock! Generators tend to grow legs and walk away when they are not locked down. This is more true when you camp with them or tailgate. A lock is not totally foolproof, but will deter the ‘honest’ thief enough to make it not worth it.
Yep, they are pricey. I paid about 2K for both of them. Inverters are always going to cost more money for several critical reasons.
A) They are labor-intensively constructed. That is, they are built to insulate and are very tightly arranged in their cases. The insulation provides a lot of the lower decibels you will be hearing. Good things just take time to make, and part of the cost is wrapped up in that.
B) Portability: This goes back to the tightly constructed package they come in. The 2000is model weighs about 45 pounds minus the gas. Try going to a Home Depot and lifting a construction grade generator. Not fun.
Awesome Quiet Little Inverter-Generator!
I purchased the EF2000iS 2,000 watt inverter-generator for extended fishing trips for charging 12 volt marine batteries and for running corded power tools in remote areas. At first I wasn’t sure if the 2,000 watt model would be enough power to meet my needs, but I decieded to take a chance with it because of the price, and boy am I glad I did.
It easily powers drills, grinders, skill saws, table saws, sawzalls, and portable cement mixers – pretty much anything that draws under 16.7 Amps. Most power tools draw up to and under 15 Amps. My industrial right-angle concrete drill only draws 8 Amps, and that thing is rugged. It’s more than enough for my needs for working in the woods where I can’t just “Plug In.”
Another thing that’s slick about it is it also charges marine batteries and has its own special DC receptical and comes with the included cable. You just fire it up, hook up the terminals to your battery, then plug in the cord. It doesn’t have a charge meter built in, so I purchased a hand held battery tester and check the charge level once an hour. I think the battery tester was under $30 (a good investment).
With that in mind, I used it last Memorial Day weekend during our Men’s Family Fishing Trip out at Johnston Pond camp here in Maine, out in the woods roughing it with tents. The area is surrounded with small-ish ponds, so my dad and I brought our little skiff and trolling motor with us (too small ponds for our larger, 2-stroke boat). We brought two 12 volt marine batteries with us to make sure we could spend the whole day out each day, then that evening charge one or the other up so it was ready for the next day. It worked great, we didn’t have to worry about running our batteries low and having to paddle all the way back to the landing. Peace of mind is nice.
This unit really is really quiet. There were five of us on the fishing trip, two younin’s – my friend and I, and three old farts – my dad, uncle, and elderly cousin. They complain about everything (old people tend to do that, haha). I figured someone was going to say something about the generator being noisey and I’d catch hell for it or something, but actually, everyone did nothing but praise how quiet it was. After it’s been running for 15 minutes or so, you kind of forget that it’s even there. Unlike our neighbors at a site a ways away from us, who had an old style generator that they ran at night, we could hear them having to hollar at each other in order to talk.
On top of all that goodness, since it’s an Inverter as well, you can also safely power computers, charge cell phones and iPods, run a tv and DVD player, and plenty of other things, if that’s what you’re into while camping, or in an emergency situation.
It starts up really easy. Mine started first pull right out of the box (make sure to put oil in it first, it’s not included), and still does every time. If you run it on Eco Mode (tv’s, appliances, ect.) I’m not sure how long the tank will last you hour-wise, I haven’t used it for that application yet, but in full power mode, meaning you’re constantly getting the amped up rpms for more amperage, the one gallon tank lasts for about 6 hours or so. I’d figure that it’d almost double that in Eco mode, and it’s twice as quiet. You can stand right next to it and it’s like a little humm.
I give the Yamaha EF2000iS five stars hands down for the price and performance. I’m really happy I didn’t go ahead and go with a knock off lesser brand. It was well worth the extra money for something that’s going to be reliable and dependable. There’s no sense in paying $500 or less for something that’s just going to be junk in a few months.
If you need a medium duty Inverter-Generator, I highly recomend it. You will enjoy it. It’s also very light and compact. Transporting it isn’t a problem at all.
Yamaha 2000 EFiS Gen
Received this product and filled with oil and gas and it started on the third pull. All subsequent times it has started on the first pull of the starter cord. More money than a comparable Honda 2000 but it has a number of advantages.
1. All controls are on one side on an integrated simple control panel including the starter pull. Honda controls are scattered on both sides.
Much easier operation in confined spaces.
2. Has a very visible fuel gage. Not supplied on the Honda
3. Has a carb fuel shut-off which allow you run the fuel system dry for storage. No such system on the Honda
4. The carb bowl has a drain screw and drain tube to remove all remaining fuel-if any. No easy carb drain on Honda.
5. Unit weighs over 50 lbs with a full fuel tank and oil but lighter than a Honda and every pound is important when carrying this weight.
6. Overall service and maintenance is very easy.
7. Low pollution total operating hours are twice the Honda
8. Larger carry handle.
9. Very quiet at all speeds – extremely quiet at the eco throttle or low speeds/low loads.
Researched the low cost Chinese knock-offs and there really is no comparison from a noise and weight factor. The comparable Honeywell and Kipor etc are about ten pounds heavier for comparable output specs. Ten pounds additional is about 60 lbs wet and 20% difference but a huge amount when carrying any distance.
Overall well worth the money for an extremely well designed quality product that is Yamaha’s reputation. Amazon service and delivery was spot on as usual.
I agree with the other reviews. An excellent generator all around. I purchased this mainly for tailgating and emergency use. It is as light and as quiet as everyone else says it is.
What i thought would be more helpful is what the generator will run and not run. It easily powers a 1500w space heater. It handles the starting surge of my 22 cubic foot fridge just fine and keeps everything nice and cold/forzen. Powers my 1650w microwave without a problem. It runs a 10,000 btu window AC unit without complaint. After reading the review about the hairdryer, I hooked up my wife’s 1875w dryer and ran it on ‘high’ and ‘hot’ for 10 minutes. Even though this wattage is well above the stated 1600 continuous watts this generator is rated for, the overload light never came on, and the hair dryer acted as if it was plugged into a normal outlet. Heavy-duty ‘shopvac’ was not an issue, same with lights and TV’s.
All in all, I am happy with this purchase, and can’t wait to use it some more.
#### UPDATE 9/9/11 #####
I have had this generator for about a year. I used it weekly last football season for tailgating. Fired it up two weeks ago for the first time since December and changed the oil in anticipation of another tailgating season. It started on the second pull… all I did to prepare the genny for storage last winter was run fresh gas with Stabil in it for about 15 minutes, and as I said, it started on the second pull. Can’t beat that.
Normal tailgating load consists of 3-4 crock pots (anywhere from 250-350W apiece depending on temp setting) a 42″ LCD TV, satellite receiver, and a small stereo. With everything on, the RPM of the genny is just slightly lower on ‘ECO’ mode then when ‘ECO’ is switched off. Never overloaded it with this set up. 6-8 hours of tailgating with this load will eat up about a gallon of gas, which isn’t too bad considering the genny is probably carrying close to a full load.
Yamaha EF2000iS … Register Warranty & Test
We purchased this item for Christmas and it arrived in good condition. Unit was packed well, was very quiet in operation, and ran great. It operated much longer for the same amount of gas than a 1000 watt 2-cycle generator from a different company.
After On/Off operation of two weeks with no problems it stopped running. We checked the oil and it looks fine, but when the unit was tilted you could hear a rattling sound. We delivered the unit to an authorized service center and learned that if the machine is not registered they will not service the unit. (We hadn’t yet registered, shame on us, and immediately did so on-line that day.) The next day the service center happily accepted the unit for warranty repair.
The engine mechanic reported that the engine had dropped an exhaust valve and jammed the cylinder scratching the piston and ruining the Head. The unit’s design for a keeper is a simple locking ring and apparently was insufficient in keeping the spring from pushing the valve into the engine cylinder. (We don’t know if this is a simple defect or design flaw.)
Judging from the fact that the generator had run less than 50-hours, our estimate, we are assuming this is a defect. The repair tech said Yamaha would cover the cost for a new head and we would get the generator back in a week.
I’ll update this review after we get the unit back and have run it for another 50-hours or so. Up to the point of failure I would have given this unit 5-stars, but instead gave it two stars.
Yamaha replaced the generator in March with a new unit for free with no extra charges and after 40hours of operation the unit runs just fine. The mechanic doesn’t know why the valve failed and for now we are very happy with the unit. I’m raising the rating to 4-stars.
Expensive but good…
We bought this generator about a week ago to run our 24ft travel trailer when dry camping. It is comparable to Honda in price and quality. The only real reason to favor one over the other, is if you have a personal preference for one company’s products. We bought the Yamaha primarily because my girlfriend liked the blue color (“it was cuter”).
I ordered the unit with Amazon’s Prime account, which gave me free two-day shipping. It arrived right on time.
I unboxed it, added oil and gas and followed the directions on starting. It started on the first pull!
Plugged in the trailer, with nothing running except the built in power system and a couple of lights, the generator did not even speed up past idle. When I started up the 1000 watt microwave it did speed up as it should and ran the microwave fine.
It is really quiet. It is quite possible to carry on a normal conversation within about 10 feet of the unit. We walked around to a few nearby campsites and you could not even hear the generator over sound of the wind in the trees and the stream.
You can buy some of the chinese knock-offs for about half the price, but we wanted quiet and reliability. Overall, a top quality product.
Smooth running/starting generator…but remember its limitations
While I didn’t purchase my Yamaha EF2000IS through Amazon, I thought I had done my homework in researching its power capabilities. I checked the power needs of the microwave in my Cardinal 31 foot 5th wheel and my wife’s hair dryer, and according to the EF2000IS’ specifications the generator should have adequately powered these appliances separately. I had no illusions that the unit would power my 15,000 BTU air conditioner. The generator labored mightily to get the microwave (1450 watt) up to speed, but in a one minute cycle, a cup of water’s temperature was barely tepid. The hair dryer’s motor worked slowly and only put out warm air, certainly not enough to dry a person’s hair.
On a positive note, the EF2000’s generator kept my batteries charged and ran all the lights, television and DVD player, and coffee maker with no difficulty on a four day camping trip in the California Sierras. The grandkids may have been happy, but my wife had some grumbles.
Much of what others have reported about the EF2000’s positive points ring quite true…easy starting, exceptionally quiet even under load, and easily transported from vehicle to campsite. For lesser power needs in the outdoors or while boating, I would heartily recommend the Yamaha EF2000IS inverter generator. However, if your respective appliances are remotely pushing the power specifications, one might look into the EF2400IS or the Yamaha 3000 models.
YAMAHA 2000 UPDATE: My generator knowledge has increased somewhat since I wrote my original review. I took my Yamaha into the local dealer and the technician performed a bench test. My generator was running up to specification. The dealer asked about the altitude at which the unit was being operated. I told him I was camped at about 7500 feet. He said studies suggest that a generator will lose 3% of its capability per 1000 feet of elevation. In addition, appliances like microwaves have significant start-up draws of power. After further experimentation at sea level, my microwave worked normally as did other appliances that might have caused me concern.
Love my Yamahas
Can’t testify to longevety yet, but I have been running a pair of new EF2000iS gennies on my travel trailer for two weeks. I run the pair to power a 15,000 BTU air conditioner and it has been HOT here. I bought these because I can’t lift the old one into the pick-up anymore. I think everything gets heaver as I get older. These little guys only weigh about 45 lb or so and I can handle them.
The little Yahamhas have been running nearly continous for about 6 days & most of the nights without a glitch so far. Most quiet generator that I have almost never heard (Have not had a chance to compare with Honda) and all my neighbors agree. Even at full power needed to run the A.C., you can hardly tell they are running at 60 feet and can’t hear them at all in the camper from 15 feet away. Nobody cares if I run them late at night cause their generators are running much louder!
Each one will run everything but the A.C. by itself and the ECO setting is REALLY quiet. I can’t really tell just how long a tank of fuel lasts because I have been refueling every 4 hours of so at full throttle. I am kinda chicken to let one of them die while the A.C. is on…afraid it might overload the other or cause a problem with the A.C. itself. I want to get a dual extended run fuel tank, but none of them appear to be for the 2000iS. Mostly a difference in the fuel cap I think.
Anyway, I will have the first 100 hours on my pair this month. I will know in a few months if they are worth the money…but I bet they are!