Does Changing to High Throttle Change Engine Feel? | Throttle Winding Diameter to be Careful When Replacing Parts

From fully closed to fully open, the rider is constantly performing delicate throttle control when riding a motorcycle.
Not only is it important that the throttle wire operates smoothly without snagging, but throttle opening is also important. High throttle = high throttle may be installed in customization and tuning, but it is important to understand its purpose and effects and utilize it correctly.

High throttle, can increase shaky feeling at low openings to the extent that full throttle is achieved at low openings.

For owners who have found the aftermarket high throttle kits to be unwieldy, we combine factory parts to create low throttle kits.

The standard customization and tuning around the throttle is high throttle = high throttle. Low-Throttle is a synonym for High-Throttle, but what are the characteristics of each? The advantage of Hi-Slo over Low-Thro is that full throttle opening can be achieved with less throttle opening.

As you can see when you have the opportunity to fully open the throttle during sports riding or track riding, the OEM throttle opening low throttle has a large angle from fully closed to fully open, which requires a large twist of the wrist, so you may have to re-grip the throttle in the middle of the ride. The major advantage of changing to high throttle is that the throttle opening angle becomes smaller, allowing control from fully closed to fully open without having to re-grip the throttle.

Also, since the throttle opening to full throttle is smaller = larger throttle opening per fixed angle, opening the throttle in the same way as low throttle opens the throttle valve of the carburetor or injection system, which improves throttle response and makes it feel as if more horsepower is being produced.

However, there are some disadvantages to high throttle. In the case of piston-valve carburetors such as the Keihin PE and Mikuni VM, which are often installed in 4-stroke minis, the piston stroke is small for the small-diameter type, so when the opening angle is reduced in Hi-Slo, the piston opens wide with slight throttle operation, resulting in reduced control in the low and mid-speed range. This can result in loss of control in the low and mid-speed range.

This disadvantage occurs not only with small-displacement motorcycles but also with medium- and large-sized motorcycles. Especially in the case of large vehicles, the torque from low speeds is high, so the high throttle may accentuate the jerkiness of the vehicle when driving in town.

The OEM throttle opening and high throttle specifically differ in the wire take-up diameter of the throttle pipe.
The higher the high throttle degree = the smaller the throttle opening to full throttle, and the larger the winding diameter. Active, a parts manufacturer, offers several types of throttle pipes with different take-up diameters, and for major models, the throttle opening angle for each take-up diameter is also listed on its website.

If you want to know how much the degree of opening changes by changing the wire take-up diameter, you can refer to these data and know that you can reduce the difficulty of riding by keeping in mind that the change in the opening should not be too extreme.

Changing the throttle pipe winding diameter also takes into account the amount of wire winding

Since the throttle holder for the Hi-Slo kit does not fit the OEM throttle pipe, the throttle holder is also diverted from the OEM part.

Compared to the left OEM holder, the right holder for high throttle has a larger wire take-up diameter due to the tyco-hooking position of the right holder for high throttle being farther from the center, so if the throttle grip opening is the same, the amount of inner wire take-up will be larger. Even if the grip opening degree is smaller, the throttle valve opening degree change will be larger, which may affect the ease of handling, especially in the low opening degree range.

The OEM throttle holder has a brake lever mount, but a separate brake holder was installed when the high throttle kit was installed, and the lever mount portion of the OEM holder was cut off and attached to the handlebar for continued use.

The smaller diameter of the rewind increases the degree of throttle opening, resulting in a gentle increase in engine rpm at startup and improved ease of handling. While the higher-throttle setup is effective for sports driving, where the throttle opening angle is greater, the OEM low-throttle setup has the advantage of calmer handling if the main focus is on city riding.

As mentioned earlier, increasing the winding diameter of the throttle wire will reduce the throttle opening and allow for higher throttle speeds, but some precautions should be taken when combining general-purpose parts or OEM wires instead of a dedicated kit set up for each model.

The most important factor is the change in throttle inner wire length due to the increased throttle pipe take-up diameter. As the take-up diameter is enlarged, the amount of inner wire exposed on the throttle valve side is reduced, resulting in a change in the positional relationship with the throttle drum of the carburetor and throttle body, and the throttle may not be fully closed even with maximum free play at the adjuster portion.

To cope with this situation, some throttle pipes for Hi-Slo have multiple holes to hang the inner wire tycoons, allowing adjustment of the amount of inner wire exposed on the throttle drum side.

Also, as a matter of course, if the throttle pipe take-up diameter increases with higher throttle slots, the throttle holder often needs to be changed, and if the throttle holder incorporates a kill switch or cell motor button, the right side handlebar switch also needs to be replaced.

High-throttle conversion is certainly an effective component for sport riding, but it is important to understand the advantages and disadvantages and to take into account the technical requirements for installation before making a choice.