When people compare the Yamaha F20 vs F25, the deciding factor is usually the boat’s horsepower rating and how much weight you are pushing: the F20 suits light tenders, jon boats and small aluminum hulls where 20 hp is the limit or plenty, while the F25 gives you a little more punch for the same class of boat without a big jump in size. The F40 is a step up into Yamaha’s midrange, built for heavier boats, small pontoons and fishing rigs that need more power and often remote controls.
All three are four-stroke Yamaha outboards with a long track record, and all three come in several versions. Here is how I walk a customer through the choice.
Yamaha F20 vs F25 vs F40 at a glance
| Model | Yamaha grouping | Best fit | Typical setup |
|---|---|---|---|
| F20 | Portable | Tenders, jon boats, small aluminum boats, light skiffs | Tiller, manual or electric start |
| F25 | Portable | Same hull types where a bit more power helps with load or chop | Tiller or remote, manual or electric start |
| F40 | Midrange | Larger aluminum fishing boats, small pontoons, heavier skiffs | Tiller or remote, electric start, power trim and tilt on many versions |
Yamaha itself groups the F20 and F25 with its portable motors and the F40 with its midrange line, and that tells you a lot. The F20 and F25 are motors one or two people can still handle on and off a transom with care. The F40 is a different class of motor, and it is usually bolted on and left there.
Start with your boat’s capacity plate
Before you compare motors, look at the capacity plate on your boat. It lists the maximum horsepower and the maximum weight the hull is rated for. Never exceed it. If your plate says 25 hp, the F40 is off the table no matter how much you want it. If it says 20 hp, the F25 is off the table too. The U.S. Coast Guard Boating Safety site explains why these ratings exist.
Weight is the other half of the equation. Engine weight sits right at the transom and changes how a small boat floats and handles. The installed weight is also more than the dry weight once you add a battery, fuel and controls. Our article on outboard dry weight vs installed weight covers what to add up. Get the exact dry weight for the specific model and year from Yamaha’s spec sheet, because it varies between versions.
Yamaha F20 vs F25: which one makes sense?
The F20 and F25 are close relatives in size and purpose. Choose based on the job:
- Pick the F20 if your boat is rated for 20 hp, you run light loads, or you want to keep things simple. A tiller model like the Yamaha F20SMHA is a classic small-boat setup.
- Pick the F25 if your boat is rated for 25 hp or more and you often carry two or three people, gear or a cooler. The extra power helps you get on plane with a load and gives you a bit more margin in chop. The Yamaha F25LMHC is a long-shaft tiller version.
The F25 also comes in remote-control versions, such as the Yamaha F25LWTC, which suits a small center console or a side console boat. Fuel system details, such as EFI versus carburetor, have changed across model years for these motors, so check the spec sheet for the year you are buying rather than assuming.
When the Yamaha F40 is the better choice
The F40 is the motor to look at when the F25 is working too hard. Typical signs: a heavier aluminum fishing boat, a small pontoon, a boat you load with people and gear every trip, or a hull rated well above 25 hp. The F40 is a bigger, heavier motor with more torque for pushing weight.
Because of its size, plan the install properly. Many F40 versions have power trim and tilt and are rigged for remote steering, which means controls, cables, a battery and a solid transom. The Yamaha F40LEHA is a tiller version for owners who want 40 hp without a remote console. Read our checklist on outboard controls and rigging before you switch from a tiller to remote steering.
Reading Yamaha model codes
Yamaha model codes carry useful information. The parts that are consistent and widely documented:
- F: four-stroke.
- Number: horsepower.
- S or L right after the horsepower: shaft length. S is a short shaft, around 15 inches, and L is a long shaft, around 20 inches.
- M or E: manual start or electric start.
- H: tiller handle.
- Last letter: the model generation or version code.
Some codes use other letters for tilt and trim or for combined start options. If a letter is not in the list above, confirm it in the Yamaha literature or the product description. A model like F25LMHC reads as 25 hp, long shaft, manual start, tiller handle. On a motor you already own, the full code is printed on the identification decal on the transom bracket.
Practical buying tips
- Confirm the hull’s maximum horsepower and the transom height before anything else.
- Decide tiller or remote. That choice narrows the list of versions quickly.
- Decide manual or electric start. Electric start adds a battery and charging setup.
- Compare weight against what your transom and crew can handle.
- Plan the propeller. The right pitch matters as much as the horsepower.
For official specs, owner’s manuals and dealer support, check Yamaha Outboards.
Shopping Yamaha outboards
When you know the horsepower, shaft length and control setup you need, browse the Yamaha outboard range or compare across brands in our outboard motors category. Match the full model code on the listing to your notes and check the product page specs before ordering.
Frequently asked questions
Is the Yamaha F25 much bigger than the F20?
No. Yamaha groups both as portable motors and they serve the same kind of boats. The F25 gives you more power in a similar package. Compare the exact weights for the model years you are considering on Yamaha’s spec sheets.
Can I put an F25 on a boat rated for 20 hp?
No. Stay within the maximum horsepower on your boat’s capacity plate. If your boat is rated for 20 hp, the F20 is the right Yamaha choice.
Should I choose a Yamaha F40 or two smaller motors?
For most small boats a single F40 is simpler to rig and maintain. Some owners add a small kicker motor for trolling or as a backup, which is a separate decision from the main motor.
What does the L in F25LMHC mean?
L means long shaft, about 20 inches. An S in the same position means a short shaft, about 15 inches.
Start with the right reference 
Plan the arrival Always confirm the exact model, part number, condition and included components on the product listing. For a compatibility question, contact TorqueHarbor before ordering.