501 Bluff Ave. St. Charles, MN 55972
(507) 932-3477

Design & Technology

Craftmanship

Our Trikes are designed to utilize factory components from the original motorcycle. We incorporate OEM suspension, finaldrive, lights, seating and exhaust wherever possible. This makes maintenance, service and accessory installation simple and convenient.

Fiberglass Technology

Original body designs are crafted to complement and enhance the style of the original motorcycle. We utilize the most current production methods, like vacuum resin transfer molding (RTM) and urethane plastic injection molding. Fiberglass technology has advanced significantly since the old days of chop guns and hand-lay open molds.

All of our paint and preparation takes place in a downdraft, climate-controlled environment. Primer and topcoat finishes are baked to ensure consistency and durability. We specialize in color matching the most beautiful factory finishes available in the motorcycle industry.

A Passion For Precision

Our Trike conversion kits are engineered and manufactured to provide superior handling, performance, and reliability. This commitment to original thinking and leading edge design has resulted in such developments as the famous Lehman "No Lean" suspension, which offers exceptional high-speed handling and confidence inspiring maneuverability. We also offer the most effective Trike braking systems that have been tested to date.

The Ride Of Your Life

Timm's Trikes offer an exceptionally stable ride and nimble handling characteristics, ideal for touring at highway speeds. You will enjoy unmatched versatility and convenience. Add to that, supreme comfort and the exhilaration of the open road and you have a one of Timm's Trikes.

Suspension

Trike Suspension and Swingarm Dynamics

There are basically two common suspension systems currently in use on Trikes today. They can be identified as either “independent” or “solid axle.” Both systems each have their own unique advantages and disadvantages.

“No Lean” Advantage

The “No Lean” philosophy begins with a solid, one-piece swingarm that is designed to be the most sturdy and inflexible in the industry. What this does is completely minimize the Trike’s ability to sway or roll to the outside of a corner. The noticeable benefits are increased stability and easier steering, especially at highway speeds.

At Timm's Trikes, we will not compromise performance and safety to achieve incremental gains in low speed ride compliance. We strongly feel that independent suspension technology that is appropriate for a 4-wheeled vehicle does not account for the unique characteristics of a 3-wheeled vehicle using a motorcycle front-end.

1. What is “No-Lean” suspension?

The single greatest factor that determines how a Trike performs is swing-arm design. No other single component has such an impact on handling and ride quality. “No-Lean” refers to the proprietary design, which minimizes flex in the swing-arm and rear-end system. This design features a differential rear-end with internal solid axles. The swing-arm is a one piece reinforced design, specially constructed to reduce all torsion effects.

2. Why should the swingarm be so rigid?

Performance. The way to maximize stability and improve handling is to use the most rigid one-piece swing-arm possible. Using a rigid swing-arm ensures that while cornering, all three wheels remain firmly planted on the ground, while the center of gravity stays where it belongs - centered over the rear end. Flex within the swing-arm would cause the Trike to lean resulting in decreased stability and heavier steering.

3. How does “No-Lean” suspension compare to independent suspension systems?

“No-Lean” is the exact opposite of independent suspension. Independent platforms are designed to allow shock compression on one side of the Trike while allowing extension on the opposite side. For this reason, body roll or “sway” must be expected. Body roll shifts the center of gravity to the outside wheel in curves and creates a less stable condition. To compensate for this, the rider must slow down or the Trike may tip over. In effect, a Trike with independent suspension will tip easier and faster, due to the center of gravity shifting towards the outside of the Trike. The addition of anti-sway devices simply limits this tendency by restricting the independent movement, which also limits the smooth ride benefits.

Steering

Although there are many kits on the market that change Trike steering geometry, the affect of these kits on Trike handling characteristics is often not fully understood. Rake is the angle measured between the steering axis and vertical. The steering axis is the line about which the steering system turns. Although the angle of the fork tubes from vertical is often the same as the rake angle, they are not always the same. Trail is the distance measured from where the steering axis meets the ground to where a vertical line drawn though the front axle meets the ground. It can be thought of as the distance that the front wheel “trails” the steering axis.

The effects that rake and trail have on steering performance can best be explained using a shopping cart front wheel as an example. The front wheel of a shopping cart is a castor that has a vertical steering axis that is in front of the wheel. The vertical steering axis results in zero rake, and having the pivot in front of the wheel results in a significant amount of trail.

This results in the front wheel tracking directly behind the pivot regardless of the direction the cart is pushed. If the vertical pivot axis were directly above the wheel axle, the wheel would not track directly behind the pivot. In this case both the trail and the rake would be zero resulting in a wheel that has as much possibility of turning sideways as it does going straight. This is a very unstable condition for both a shopping cart and a motorcycle. Motorcycles and Trikes both use a certain amount of rake and trail to ensure proper handling and steering response. In general, more rake provides greater straight-line stability, less rake makes the bike more responsive. This is why the forks on a sport-orientated motorcycle are more vertical than those on a cruiser or touring motorcycle. In short, smaller rake values result in quicker steering, while larger rake values result in slower steering.

Driveshaft

basic drive shaft system

The purpose of the shaft is to transfer power from the motorcycle transmission to the differential. The universal joints are required because the differential is offset and at an angle to the transmission.

Driveshaft Angle

All universal joints are designed to have a minimum of 1/2 degree of working angle. This angle is necessary in order to keep the needle bearings contained in the caps rolling. At angles less than 1/2 degree, the needles stay locked in the same position and wear into the cap, causing vibration and eventually failure.

The Vibration

All universal joints vibrate. This is a property due to the design of the joint. So the next question is: "If universal joints vibrate, then why does my car not vibrate?" When a drive shaft is designed for application in a car, the joints are always in pairs. When there are two joints, they can be phased so they cancel each other out and no vibration is felt.

Universal Joints

When the output shaft turns, the two caps of the front universal joint must turn around the center of the output shaft. When we look at the opposite side of the universal joint the other two caps on the universal joint must turn about the center of the drive shaft. Because the drive shaft is at some angle to the output shaft, the cross of the universal joint must wobble back and forth to allow the bearing caps to trace these circles out while rotating. This causes the rotating speed of the drive shaft to fluctuate on every turn, at first speeding up slightly faster than the output shaft, then slowing to slightly below the output shaft speed.

If this effect is not counteracted with a second universal joint, it will create vibrations. At the other end of the driveshaft, there is a second universal joint. This joint is timed to the front universal joint in order to be exactly opposite to it. When the drive shaft speeds up from the action of the front universal joint, the action of the rear universal joint slows it down, and vice versa. This produces a constant shaft speed at the differential shaft. Automotive drive shafts are not straight for the reasons explained above. The rear end moves up and down, so the drive shaft can never be perfectly straight.

© 2014 Timm’s Trikes Inc. All rights reserved. Designed by Tension Design