Nakamoto Transport — Japan
Three Isuzu Elf trucks were treated on 25 February 2023 and measured over the following three months: +5.6%, +7.2%, +22.9%. The largest improvement is on the truck with 93,566 km on the odometer; the two with more than 240,000 km improved least. If the treatment worked mainly by clearing accumulated combustion deposits, this is the wrong way round — and we would rather say so than leave it out.
Three trucks, one clean result, and a pattern that does not fit the story we tell about how the product works.
| Operator | Nakamoto Transport, Japan |
|---|---|
| Vehicles | 3 Isuzu Elf trucks (2 t and 3 t), model years 2016 to 2018 |
| Application | 25 February 2023 — 60 cc on the 2 t trucks, 90 cc on the 3 t |
| Measurement period | 1 March to 31 May 2023 |
| Measured quantity | Fuel efficiency in km/L |
| Result | +5.6%, +7.2%, +22.9% — median +7.2% |
| Notable | The lowest-mileage vehicle shows the largest effect |
Every measurement, not just the best one
| Vehicle | Odometer at application | Applied | Before (km/L) | After (km/L) | Change |
|---|---|---|---|---|---|
| Isuzu Elf 2 t (July 2016) | 271,307 km | 60 cc | 7.32 | 7.73 | +5.6% |
| Isuzu Elf 3 t (March 2017) | 247,005 km | 90 cc | 6.91 | 7.41 | +7.2% |
| Isuzu Elf 2 t (February 2018) | 93,566 km | 60 cc | 5.16 | 6.34 | +22.9% |
| Median across the three trucks | +7.2% |
Method before result
All three trucks were treated on the same day and measured over the same three-month window, on the operator’s normal distribution work. The applied quantity followed the vehicle size — 60 cc on the two-tonne trucks, 90 cc on the three-tonne.
A three-month measurement window is one of the better features of this dataset. Our own field-testing method recommends at least three months of records: some documented trials have shown a measurable signal within weeks, but a longer window still separates a real treatment signal from normal variation more reliably than a short one.
The pattern across the three vehicles is what makes this page worth reading. The 2018 truck, with 93,566 km on the odometer, improved by 22.9%. The 2016 and 2017 trucks, both past 240,000 km, improved by 5.6% and 7.2%. The usual explanation for how an intake-air treatment works — progressive removal of combustion deposits — predicts the opposite: the dirtier, older engine should have more to gain.
The limits of this trial
We publish these next to the result rather than in a footnote. If a limitation would change how you read the number, you should read it at the same time as the number.
Known limitations
- Three vehicles. A pattern across three data points is an observation, not a finding, and could easily be coincidence.
- Odometer reading is a poor proxy for how sooted an engine actually is. Duty cycle, service history, fuel quality and idle time all matter more, and none of them is recorded here.
- The applied quantity differed between vehicles, so vehicle size, engine and dose all vary together and cannot be separated.
- There is no control group, and the three-month window covers the transition from winter to spring, which reduces consumption on its own.
- We hold a summarised record of this trial, not the operator’s primary data. The method, the periods and the per-vehicle figures are documented; the underlying fuel and distance logs are not in our possession, and we have asked for them.
Reading this evidence in context
We publish this because it cuts against our own mechanism story. If the effect were purely about cleaning up an old, dirty engine, the two high-mileage trucks should have led. They did not.
That does not disprove the deposit explanation — three vehicles cannot — but it does mean we should stop presenting it as settled, and it is a reason to be sceptical of anyone who tells you an older fleet will automatically see more.
The useful part for an operator is the timing rather than the mechanism: one application, three months of measurement, results in the mid-single digits to low twenties. That is the shape of trial we would design.
Questions operators ask about this trial
Does the treatment work better on old engines or new ones?
Is a three-month measurement long enough?
Why did the trucks get different amounts of product?
Provenance
- Operator
- Nakamoto Transport, Japan
- Application
- 25 February 2023
- Measurement period
- 1 March to 31 May 2023
- Source
- Japanese field-study summary — derived record
- Recalculation
- All percentages recomputed from the recorded km/L values
- Open items
- Primary records requested; service history and duty cycle of the three vehicles
- Last checked
- 15 August 2026
The only baseline that matters is yours
Every trial on this site was run on someone else’s vehicles, duty cycle and baseline. A NanoEFX pilot measures yours — and we will help you design it with a control group so the result stands up.