Motorcycle Lowering: Pros and Cons! Plus Methods and Costs Explained

What is motorcycle lowering?

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Motorcycle lowering refers to the customization of reducing the seat height (the height from the ground to the seat) of a motorcycle, primarily done to improve footing.

It's called "lowering" because it involves making the motorcycle "low" and "down." The basic method for lowering is to adjust or change the suspension.

Main purposes of lowering a motorcycle

The main purposes of lowering a motorcycle are as follows:

Improve footing
Increase sense of security
Seek a change in appearance

Lowering a motorcycle reduces the seat height, which improves footing and increases stability when stopped.

In particular, having both feet firmly on the ground increases a sense of psychological security and reduces the risk of falling, such as making it harder to drop the bike.

Additionally, lowering the motorcycle lowers its center of gravity, which affects its appearance, making it look more stylish.

Advantages and disadvantages of lowering a motorcycle

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Motorcycle lowering has both advantages and disadvantages, so it is recommended that those considering it weigh both aspects before making a decision.

Performing lowering without careful planning can alter the handling and riding feel, so it's important to make a cautious decision.

Advantages

The advantages of lowering a motorcycle are as follows:

Improved footing
Effective in preventing drops
Easier to maneuver
Stylish appearance
Sense of psychological security

Lowering a motorcycle reduces the seat height, which improves footing. Better footing makes it harder to drop the bike and enhances a sense of psychological security.

Improved footing also makes the motorcycle easier to handle, and it becomes less likely to fall during U-turns or when starting, which is a significant advantage of lowering.

Additionally, lowering the motorcycle's center of gravity gives it a stylish appearance, which can increase your attachment to the bike; this is also considered an advantage of lowering.

Disadvantages

The disadvantages of lowering a motorcycle are as follows:

Reduced lean angle
Ride comfort may worsen
Side stand adjustment required
Visual balance may be disrupted
Impact on vehicle inspection and safety standards

One disadvantage of lowering is that the reduced seat height and altered riding position can lead to a shallower lean angle when cornering, potentially worsening ride comfort.

Additionally, since the motorcycle's center of gravity changes, the side stand may need rebalancing. Depending on the extent of the lowering, the visual balance may also be disrupted.

Furthermore, for motorcycles that require inspections, changes to specifications may necessitate procedures, and headlights, taillights, etc., may no longer comply with safety standards, which is another drawback of lowering.

Methods, procedures, and items for lowering a motorcycle

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For those who wish to lower their motorcycle after understanding the pros and cons, we will explain the methods for lowering a motorcycle and the procedures for each method.

We'll introduce various lowering methods and additional options, so please use this as a reference to find the method that suits you best.

Lowering Method ① [Replacing the rear suspension]

A classic method for lowering a motorcycle is to replace the rear suspension, typically with a suspension that is slightly shorter than the genuine one.

Replacing the rear suspension with an aftermarket one can lower the bike by about 1cm to 3cm, and prices vary widely from around 10,000 yen to several hundred thousand yen, depending on the model and suspension.

If you replace it yourself, you only pay for the suspension, but if you ask a motorcycle shop to do it, you'll need to pay for the rear suspension plus labor costs (around 15,000 to 30,000 yen).

Advantages and disadvantages of lowering rear suspension

The advantage of lowering by replacing the rear suspension is that it can achieve a stable lowering without sacrificing ride comfort.

Also, many are finished with anodizing in gold or blue, which also enhances the appearance.

The disadvantage is that since the entire rear suspension is replaced, the custom costs for parts and labor tend to be high.

Lowering rear suspensions include the following:

Improved appearance and ride comfort! Recommended rear suspensions

Source: https://bikeman.jp/products/kn-kn-aslwp-gd

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"Super Absorbing Shock Low Down Gold" is a lowering rear suspension for HONDA PCX 125 and 150.

It offers a smooth ride with less harshness, and its special design makes it less likely to interfere with the crankcase even when the suspension is leaned.

Product Name: Super Absorbing Shock Low Down Gold
Manufacturer: KN KIKAKU
Size: 285mm
Compatible Models: HONDA PCX125/PCX 150
Selling Price (tax included): 24,090 yen

In addition to lowering by replacing the entire suspension (shock absorber and spring), there is also a method of lowering by replacing only the spring.

Source: https://bikeman.jp/products/ac-22032211

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Hyperpro "Rear Spring Low Down" allows for easy lowering by approximately 25mm just by replacing the genuine suspension spring.

Although the image shows the product for YAMAHA MT-09, its appeal lies in its wide lineup, covering everything from liter bikes to moped classes, as well as imported bikes like Triumph, BMW, and KTM.

Product Name: Rear Spring Low Down
Manufacturer: HYPER PRO
Lowering amount: Approx. 25mm
Compatible Models: YAMAHA MT-09
Selling Price (tax included): 27,078 yen

Lowering Method ② [Install a lowering link plate]

A link plate is a part that connects the swingarm to the suspension. By replacing it with a shorter lowering link plate, the vehicle height is also reduced.

Replacing the suspension or springs with lowering-specific ones, along with installing a lowering link plate, is a common motorcycle lowering customization.

Depending on the motorcycle model, lowering link plates may be sold as genuine parts by motorcycle manufacturers, as well as by motorcycle accessory manufacturers, ranging from 8,000 yen to around 25,000 yen.

Advantages and disadvantages of lowering link plates

The advantage of lowering link plates is that they allow for easier lowering than replacing the rear suspension, while the disadvantage is that suspension adjustment may be necessary.

Also, depending on the extent of the lowering, the motorcycle may not be able to park stably with the genuine side stand, in which case it will be necessary to replace it with a short type stand.

Lowering Method ③ [Adjusting the front fork protrusion]

Adjusting the front fork protrusion refers to adjusting how much the front fork of a motorcycle extends from the top bridge.

By extending the front fork further from the top bridge, the front ride height can be lowered.

Increasing the protrusion also lowers the bike and can make handling quicker and improve cornering performance, but extreme protrusion can compromise straight-line stability and be dangerous.

Advantages and disadvantages of adjusting front fork protrusion

The advantages are that no parts need to be purchased, so if you have the tools, you can lower the front without cost, and the side view also changes its impression.

The disadvantages are that if the genuine side stand is used as is, the motorcycle becomes unstable and prone to falling, and the riding position changes.

In addition, since the range of motion of the front fork changes, the riding feel of the motorcycle also changes, which is another disadvantage.

Convenient items for front fork protrusion adjustment

Source: https://bikeman.jp/products/cj-27702437

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Adjusting the front fork protrusion of a motorcycle requires both left and right front forks to have the same protrusion amount. However, with a side stand, more force is applied to one front fork, making it difficult to adjust evenly.

In such cases, a Pro TOOLs "Motorcycle Jack" that supports the vehicle from below is convenient. With a jack, both front forks can be lifted straight, making adjustment easier.

When using a jack for adjustment, do not jack up the front tire completely off the ground; instead, lift it just enough to relieve the load on the front.

Product Name: Motorcycle Jack
Manufacturer: Pro TOOLs
Overall Length x Width x Height (mm): 495 x 90 x 305 (excluding top adapter)
Purpose: Jacking up motorcycles
Body Weight: 13kg
Rated Load: 499kg
Selling Price (tax included): 11,689 yen

Lowering Method ④ [Changing the seat]

This lowering method improves foot accessibility by replacing the seat with a thinner one, or by removing padding (shaving off foam to reduce thickness) to lower the seat height.

Depending on the motorcycle model, some manufacturers offer sports seats or low-down seats as genuine parts, which are thinner than standard seats.

While the effect is minimal for sport bikes that already have thin seats, naked bikes and cafe racers can achieve about 20mm of lowering, depending on the model.

The cost of seat replacement is around 15,000 to 55,000 yen for the replacement seat itself, and if you have a professional handle the replacement, labor costs will be approximately 1,000 to 2,000 yen.

Advantages and disadvantages of changing the seat

The advantage of changing the seat is that you can easily lower the motorcycle just by replacing the seat, making it the simplest method among all lowering options.

The disadvantage is that the ride comfort deteriorates due to the reduced thickness of the seat. Especially in the case of padding removal, the impact from bumps will be stronger, so if you don't want to compromise ride comfort, another method is recommended.

Recommended lowering seats

Source: https://bikeman.jp/products/d-48378

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The DAYTONA "Cozy Seat COMP with Seat Base" shown in the image is a lowering seat for the GB350, offering approximately 20mm of lowering compared to the genuine seat.

Since it comes with a seat base, there's no wobbling after seat replacement, ensuring a stable seat change.

Product Name: Cozy Seat COMP with Seat Base
Manufacturer: DAYTONA
Compatible Model: GB350
Lowering Amount: Approx. 20mm
Selling Price (tax included): 50,316 yen

Lowering Method ・ Exception [Wearing thick-soled boots]

If the purpose of lowering is to "improve footing," wearing thick-soled rider boots can help improve foot accessibility.

If the soles are too thick, it can affect motorcycle operability and make proper handling difficult and dangerous, so choose thick-soled boots within a range that doesn't impact operation.

Recommended motorcycle thick-soled boots

Source: https://bikeman.jp/products/d-26336

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The Henly Begins "HBS-007 Middle Boots" are stylish, thick-soled rider boots that don't feel out of place even when you're off the bike.

The image shows the 26.0cm (brown) model, but black is also available, making it easy to match with your fashion style or bike color.

Product Name: HBS-007 Middle Boots
Manufacturer: Henly Begins
Sizes: 23.5cm - 28.0cm (23.5cm - 24.5cm are women's sizes)
Price (incl. tax): ¥14,688

Precautions for Lowering a Motorcycle

When lowering a motorcycle, please pay attention to the following points:

Maintain front and rear suspension balance
For those who frequently engage in sport riding, mufflers may scrape more easily
May affect chain tension
Perform custom modifications within the scope of safety standards

Lowering a motorcycle can disrupt its front-to-rear balance, which may affect cornering. Therefore, it is generally safer to avoid lowering only one side drastically.

When the vehicle height is lowered, parts around the exhaust and footpegs may scrape more easily. Riders who engage in sport riding need to be careful, and additional customizations such as replacing with backstep kits may be necessary.

Additionally, when the vehicle height is lowered, the swingarm angle changes, which can affect chain tension. Be sure to check and adjust the chain accordingly.

If modifications are not kept within the scope of safety standards, not only will the vehicle fail its inspection, but you may also be subject to police enforcement. Therefore, it is advisable to perform custom modifications within the scope of safety standards.

Vehicle Inspection and Regulations Regarding Motorcycle Lowering

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Lowering a motorcycle improves foot accessibility and changes the visual impression of the bike, but depending on the customization, it can lead to problems such as failing vehicle inspections due to legal regulations.

Furthermore, even motorcycles that don't require vehicle inspections can be subject to police enforcement, so let's look at what kinds of customizations are not allowed.

Legal, but Fails Vehicle Inspection if Safety Standards are Not Met

Lowering a motorcycle is generally not illegal, but the following conditions must be met:

Minimum ground clearance of less than 9cm is NOT allowed
Be careful not to have turn signals or lights outside the standard height
Structural modification application is required if the vehicle height changes by ±4cm or more
Side stand angle is also subject to inspection (stability required)

The lowest part of the motorcycle, such as the exhaust, must be at least 9cm above the ground, otherwise it is a violation. Also, the position and angle of turn signals and headlights must be within legal standards.

If the vehicle height changes by ±4cm or more due to customization, motorcycles that require vehicle inspection must submit a "structural modification application" to the Land Transport Bureau. For motorcycles that do not require vehicle inspection, such as 250cc bikes, a "modification application" is required. Both applications must be submitted within 15 days from the date of customization.

Additionally, if the vehicle height is lowered, it may become difficult to balance with the genuine side stand, increasing the risk of tipping over. In such cases, replacing it with a short-type side stand may be necessary.