CRF450L / CRF450RL Fuel Tank Upgrade Guide: IMS 3.0, 4.5 & 5.7 Gallon

Tank capacity and the weight of the extra fuel

The table compares advertised capacities with the stock 2.0 US gallons / approximately 7.6 liters. Additional fuel weight uses approximately 6.2 pounds per US gallon; actual weight varies with fuel blend and temperature.

These are fuel-only calculations at nominal full capacity. They exclude differences in tank, cap and mounting-hardware weight. Advertised capacity is not a guarantee of fuel available to the engine.

Which IMS tank makes sense for your build?

3.0 gallon: start with the smallest capacity increase

The 3.0-gallon option adds one nominal gallon. Start here when that increase covers your fuel requirement with a sensible margin. It has the lowest full-fuel weight increase of these three options, which matters when frequent direction changes and technical sections shape your event.

Installation still requires attention: IMS specifies trimming to the left shroud. Plan that work before assuming the tank will accept untouched stock plastics.

Shop IMS 3.0 gallon: Black · Natural

4.5 gallon: more capacity between planned fuel stops

The 4.5-gallon tank adds 2.5 nominal gallons over stock. Consider it when your measured fuel requirement exceeds what the 3.0-gallon setup can comfortably support. Budget for the additional fuel load and the installation changes together.

IMS requires removal of specified inner stand-offs on both stock shrouds. The supplied mounting arrangement also changes how the tank and bodywork attach. Stock shrouds are retained after the required modifications.

Shop IMS 4.5 gallon: Black · Natural

5.7 gallon: evaluate usable capacity before the number on the label

This is the largest advertised capacity in the comparison. Its suitability depends on the event, the additional load and your verified usable fuel. The wing-fuel limitation deserves particular attention if your course has long, relatively flat sections.

The installation also requires modifications to both shrouds. IMS notes a gap can remain between the rear of the shroud and the separate rear plastic. Review the installation illustrations if retaining the original bodywork appearance is a priority.

Shop IMS 5.7 gallon in Black, Natural or Red →

Our selection approach: establish your fuel requirement first, then choose the capacity that covers it with an appropriate margin. Discuss the larger tank's usable-fuel limitations with us before making it the foundation of your event plan.

Build your range estimate from your own riding

A tank size alone cannot establish a reliable mileage figure. Terrain, speed, gearing, load, engine setup and riding style all affect consumption. Measure fuel use over representative conditions and use a conservative figure when planning refueling.

Planned distance = fuel allocated for the leg × measured miles per gallon. That fuel allocation must already exclude your reserve margin and any fuel you cannot reliably access.

For example, if your measured consumption is 40 mpg and you allocate 2.5 usable gallons to a leg after holding back your margin, the arithmetic gives 100 miles. Those are example inputs, not a range claim for any tank or a prescribed reserve amount.

Understand the low-fuel warning

Honda calls the dashboard warning a fuel reserve indicator. It does not provide a continuous measurement of the gallons remaining. After changing tank shape and capacity, do not assume the stock reserve specification describes the replacement tank.

Track distance and refill quantities, and establish conservative refueling points for the installed setup. Fuel visible in a tank wing does not necessarily mean it will reach the pump. Avoid using a run-to-empty test as your range-planning method.

Choose the cap system before ordering

The CRF's Only product links above correspond to IMS screw-cap configurations. The installation parts lists include the IMS cap and cap seal for those versions. The Honda cap is not the cap specified for the swap.

IMS also manufactures dry-break versions for compatible competition refueling equipment. Treat that as a separate system: confirm the tank, receiver and fueling equipment together. A dry-break tank listing does not establish that the receiver is included.

For example, IMS explicitly excludes both the receiver and the screw-cap adapter from its 3.0-gallon dry-break version. The regular cap and seal are also excluded from the dry-break parts lists. Contact us to confirm a complete dry-break configuration before ordering.

Black, Natural or Red?

The linked 3.0- and 4.5-gallon products offer separate Black and Natural listings; the 5.7-gallon listing offers Black, Natural and Red. Choose from the options on the exact product page. Color selection does not resolve the usable-capacity limitation or replace a measured fuel plan.

Installation: OEM EFI pump, tank-specific seals and modified shrouds

The CRF450L / CRF450RL is fuel injected. These IMS instructions call for transferring the OEM EFI fuel-pump assembly. There is no conventional carburetor petcock to transfer.

All three current instructions specify the supplied IMS pump O-ring instead of the original pump O-ring and dust seal. They also identify which original components and supplied fasteners belong in the assembly. Follow the instructions for your exact tank and kit revision.

• 3.0 gallon: trim the left shroud as illustrated and use the supplied shroud bolts and collars at the tank.
• 4.5 and 5.7 gallon: remove the specified inner stand-offs on both shrouds. Use the supplied upper mounting hardware; the instructions retain OEM hardware at two lower shroud locations.
• Seat and surrounding parts: check the supplied seat-hook and mounting-bracket arrangement. Tell us about aftermarket seats, radiator braces or other nearby accessories before assuming they clear the new tank.
• Fuel connections and venting: follow the prescribed routing, protect the connections from strain and confirm clearance around the tank. Inspect for leaks before operation.

Read the IMS installation instructions: 3.0 gallon PDF · 4.5 gallon PDF · 5.7 gallon PDF.

IMS recommends installation by a qualified mechanic. Work with a cool motorcycle in a well-ventilated area away from ignition sources, and follow Honda's fuel-system service procedure. Do not start or ride the motorcycle if fuel leaks are present. This guide helps you choose the parts; use the complete manufacturer instructions for the installation.

Get the right tank on the first order

Send CRF's Only your model year, intended competition use, fuel requirement, preferred capacity and color. Include any aftermarket seat, radiator protection or other equipment around the tank so we can help check the combination.

Our linked listings cover the 2019-2027 CRF450L / CRF450RL family. Select your exact application and confirm current availability, shipping restrictions and kit contents before scheduling installation. Capacity alone does not establish compatibility with other CRF450 models.

For the rest of your build, use our CRF450L / CRF450RL Rider Guide and CRF450L / CRF450RL Performance Upgrades Guide to coordinate the bike's setup around your riding priorities.

CRF450L / CRF450RL fuel tank questions

How much fuel does the stock tank hold?

Honda specifies 2.0 US gallons, approximately 7.6 liters. The IMS options in this guide are advertised at 3.0, 4.5 and 5.7 US gallons.

Do these IMS tanks reuse the stock fuel pump?

Yes. The current instructions for all three sizes transfer the OEM EFI pump assembly with the specified IMS seal and hardware arrangement.

Can I keep my stock shrouds without cutting them?

The instructions require trimming: the left shroud for the 3.0-gallon tank and specified inner stand-offs on both shrouds for the 4.5- and 5.7-gallon tanks.

Does a 5.7-gallon tank guarantee 5.7 gallons of usable fuel?

No. IMS identifies fuel retention in the wings under some conditions. Account for that limitation before selecting the tank and setting refueling intervals.

Does the original Honda fuel cap transfer?

The screw-cap installation uses an IMS cap and seal. If you need a dry-break system, confirm the separate receiver and compatible refueling equipment before ordering.

Can I use these tanks for street riding?

The featured listings are restricted to closed-course racing use and exclude street or highway use.