"If only the XR250's tank held a bit more fuel..."
The Honda XR250 is light, compact and does everything from forest tracks to touring, but one thing that bothers many owners is its small fuel tank (9.7 L).
Hunting for petrol stations again and again on a long tour, or worrying about running out of fuel deep in the mountains on a dirt road, is quite stressful.
That is why fitting the genuine big tank from its sister model, the XR BAJA (the Japan-market version of the XR250), is an interesting idea.
"How much more fuel does it actually hold?" "Does the extra weight hurt off-road?"
In this post I cover the difference in tank capacity and range between the XR250 and XR BAJA, the benefits of the big tank, and the downsides such as a heavier front end. I ride an XR BAJA (2000 model), so I also include my own experience with the big tank. However, I have not tried fitting a BAJA tank to an XR250 myself.
I have not checked the detailed fitment differences between model years and specifications, so this post focuses on the difference in specifications and how it works in practice.
If you want to stop for fuel less often and ride further without worrying, read on.
1. Specifications: how much do capacity and range change?
1-1. The tanks differ by 4.3 litres: the BAJA tank's extra margin in numbers
Here is a simple table showing how much the tank capacity changes.
| Item | XR250 (standard) | XR BAJA (big tank) | Difference |
| Total capacity | 9.7 litres | 14.0 litres | + 4.3 litres |
From the standard 9.7 L to 14.0 L: about 1.5 times the capacity.
1-2. Calculated from fuel economy: about 120 km more range on a full tank
My XR BAJA actually does about 28 km/L. Using this figure, let's compare the calculated range on a full tank.
- XR250 (standard): 9.7L × 28km/L ＝ about 271 km
- XR BAJA tank: 14.0L × 28km/L ＝ about 392 km
The difference is over 120 km! With the same fuel economy, just having a BAJA-size tank brings the calculated range on one tankful to nearly 400 km (in practice a little less, since you won't ride until the tank is completely empty).
1-3. Why it makes you feel safer on long tours and long dirt roads
With a range of nearly 400 km, you worry less about how much fuel is left, even in rural Hokkaido (northern Japan), where petrol stations are few, or deep on long dirt roads.
Just worrying less about "Will I make it to the next station?" makes touring much more relaxed.
On my XR BAJA, the fewer fuel stops are always a help. It also means I can keep riding when petrol stations aren't open yet, for example on early-morning rides.
2. Three benefits of a big tank on the XR250
2-1. Fewer fuel stops, and less stress looking for petrol stations
Even in town or on the commute, stopping for fuel often is a nuisance. By calculation, you stop for fuel about two-thirds as often, which makes life much easier.
2-2. More freedom in choosing routes for long tours and exploring dirt roads
You compromise less, as in "That route looks more fun, but there's no petrol station, so I'll give it a miss." You also worry less about stations being closed at night, early in the morning or on holidays.
2-3. The look of a genuine tank
It is a genuine BAJA tank, so I think it looks natural on the bike. I have not compared its durability with aftermarket plastic tanks.
3. Downsides and points to know before you do it
3-1. A full tank makes the front heavier: the effect on handling
Petrol weighs about 0.75 kg per litre. 4.3 litres more means that, with a full tank, the front end is about 3.2 kg heavier, by calculation.
I think you won't notice it much in town or cruising on the motorway, but on tight twisty roads the handling may feel a little more sluggish (my guess).
I have not checked whether the suspension settings need to be changed.
3-2. Downsides of the extra weight off-road (on dirt roads)
If you ride seriously off-road, such as on tough trails or a course, the extra weight at the front has a direct effect:
- It is harder to lift the front
- It feels a little heavier when flicking from side to side in tight corners
- If you drop the bike, it is heavier to pick up
- If you drop the bike, the tank may hit the ground
If you want the lightest possible off-road feel, you can choose not to fill it to the top and adjust the amount of fuel to suit the situation.
3-3. Differences between model years, and possible interference with the seat and shrouds
Even within the MD30, the specifications differ a little between model years.
- Early models (without shrouds): For the 1995 model, both the XR250 and the BAJA had a 9.7 L fuel tank. From the 1996 model, the BAJA got the big tank, and along with it the suspension was also changed (according to Honda's press information). Also, from the 1997 model, the fuel tank mounting was changed (according to Honda's press information), so take care if you swap tanks.
- Later models (with shrouds): The later XR250 has shrouds (plastic covers) on the sides of the tank, and the tank and seat shapes differ from the BAJA's. So if you fit a BAJA tank, it may interfere with the fork or the seat, or leave gaps (I have not checked this).
So to swap in the big tank, you need to know the model year of your bike and of the tank you get. Also, from the models with the big tank onwards, the XR250 and XR BAJA have different seat shapes. To get a good fit, I think the safest way is to get a genuine BAJA seat as well (my guess).
4. Summary: who is the XR BAJA big tank for?
4-1. Riders it suits
- Long-distance tourers who ride a few hundred kilometres a day
- Riders who often go to areas with few petrol stations (such as Hokkaido or the mountains)
- Riders who love exploring dirt roads and want less risk of having to turn back
- Commuters who want to stop for fuel as little as possible
Unless you ride hard off-road, I think the extra capacity outweighs the downsides.
4-2. Finally: what to check when looking for one used
I have not checked whether new genuine XR BAJA tanks are still available. If you look for a used one, online auctions, flea-market apps and used parts shops will be the main places, I think.
When you buy, check these points in the photos and description:
- Rust inside the tank: even if the outside looks clean, rust inside can block the carburettor.
- Whether the fuel tap and cap are included: if not, you will need to buy them separately.
- Dents and distortion: check that the mounting brackets are not bent.
Why not ride your XR250 further, without worrying about fuel?