Heavy-Duty Medium Size Wheely Bar

JMI Telescopes

Heavy-Duty Medium Size Wheely Bar

Regular price
$ 603.90 Sold out
Sale price
$ 603.90
Unit price


The HEAVY DUTY Version is designed for heavier equipment with the same footprint as the standard Medium Wheeley Bars and the heavier construction of the Large Wheeley Bars.  In other words, they are like Large Size Wheeley Bars with short legs (the same length as the Medium Size Wheeley Bars).
Because of the increased weight with the narrow width, there will be a greater risk due to the high center of gravity.  The equipment will need to be strapped down to the Wheeley Bars and, as with all Wheeley Bars, JMI will not be responsible for equipment tipping over.


Maximum Load:  300 lbs
Adjusts to fit tripods with tip-to-tip distance from 34" to 42.5"
See doorway measurements for more dimensions.

Tip receptacle is 2-3/4" I.D.
Raises most mounts 3-1/2" off the ground with standard wheels (5" for Astro-Physics pier mounts)
Wheel diameter is 2-3/8"  (optional 5" and 10" wheels are available)


What are Wheeley Bars?

Do you wish you had an easy way to move your tripod-mounted, pier-mounted or Dobsonian telescope from garage to patio or driveway?  Wheeley Bars (telescope wheels/dolly) were created for just that purpose.  The sturdy base with locking wheels and leveling bolts allows you to easily move, lock, level and use the complete telescope assembly.  And best of all, you don't have to disconnect and reconnect all the electrical and computer cabling.

Standard Wheeley Bars are designed to be used on hard flat surfaces only.  With the optional large-wheel upgrade, great care in maneuvering and ideal conditions, they can be used on grass, dirt and gravel surfaces.  Wheeley Bars are generally designed to be used with the tripod legs almost fully retracted to reduce the overall width.

A Word of Warning:  The heavier the telescope mounted on the Wheeley Bars, the more careful one must be in moving the complete system by pulling or pushing below the center of gravity.  JMI is not responsible for incorrect loading or operation.


What is Tip-to-Tip Distance?

To be sure that your tripod or pier will fit a particular Wheeley Bar product, it may be necessary to verify the tip-to-tip distance of the mount.  Usually, this measurement is made with the legs of a tripod fully retracted (the shortest length) and spread out completely.  Alternately, you can measure at your preferred viewing height, but be sure to allow for the height of the Wheeley Bars (listed with each product).  The tip-to-tip distance is the measurement from the outside edge of the end of a tripod leg or pier foot (where it touches the ground) to the outside edge of another tripod leg or pier foot as illustrated below.

Here are some examples of different types of tripods and piers and where to measure.

For Custom Wheeley Bars, to be sure that your mount will fit into the receptacles, we also need to know leg or foot diameter and tip style.  For instance, on the mounts shown above (numbered from left to right), the following applies:









Flat Foot



Rounded Tip



Pointed Tip



Flat Foot


Doorway Measurements

We often get questions regarding the width of our Wheeley Bars to determine if they will fit through a particular doorway.  The following information should help in making that determination.  The following dimensions do not apply to Wheeley Bars that have been upgraded with 10" large wheels.  For Universal Wheeley Bars with the 10" Large Wheel Upgrade the doorway width must be three (3)  inches wider than the tip-to-tip distance.

There are three basic measurements as noted above.  The maximum width (X) is measured in a similar fashion as the tip-to-tip distance except that the measurement is made to the outside corner of the legs or leveling screws (typically about 3" wider than the tip-to-tip measurement of a pointed tip tripod mount).  The minimum measurement (N) is from the end of one leg to the inside measurement on the opposite side.  This would help in determining the narrowest door that the Wheeley Bars could possibly be maneuvered through.  A third measurement (W) is in between the other two and gives the width as measured from the end of one leg to the outside measurement of the opposite side.  The diagrams below illustrate the three measurements.

The illustration on the left shows the Universal Wheeley Bars turned so they can be pushed through the doorway based on the NORMAL width (W) without having to do any special maneuvering.  The second illustration shows the Universal Wheeley Bars being maneuvered by twisting them through the doorway based on the absolute MINIMUM dimension (N).  The third illustration shows the Wheeley Bars being blocked from moving though a doorway because they are positioned such that the MAXIMUM profile (X) is being presented.

Universal Wheeley Bars are called Universal because they are made to be adjustable to handle various sizes of mounts.  This means that the measurement we have been talking about can vary depending on the in-out adjustment of the Wheeley Bar legs.  The table below shows the minimum and maximum for the different widths indicated by the variable W, N and X.

Width Dimensions for Universal Wheeley Bars


Normal Width

Minimum Width

Maximum Width














Medium HD














Extra Large















What Size Wheels Should I Purchase?

The small 2-3/8" hard-rubber wheels are good for flat hard surfaces with no cracks or grooves.  For hard surfaces, such as concrete sidewalks, with seams or cracks, the 5" polyurethane wheels are best.  The large 10" all-terrain pneumatic rubber-tire wheels are designed for field use on rough surfaces such as grass, dirt and gravel.  However, great care must be taken in maneuvering on these surfaces, particularly when wet, because the wheels may sink below the surface.  We do not recommend using Wheeley Bars on these surfaces under adverse conditions, especially if you have a very heavy telescope.


Selecting the Right Wheeley Bars

When deciding on which Wheeley Bars to purchase, there are several things to consider.  These include:

The TYPE OF EQUIPMENT you will be transporting
The TIP-TO-TIP DISTANCE of the tripod feet
The TOTAL WEIGHT of the equipment to be transported
The SURFACE you will be moving the equipment over

Dobsonian telescopes should use one of our Dob-style Wheeley Bars based on which Dob you have.  Telescopes with a tripod should use one of the Universal-style Wheeley Bars.  The size will depend on the size and weight of the telescope equipment (see below).

The Universal-style Wheeley Bars show a minimum and maximum tip-to-tip distance for the tripod legs.  The best way to measure the tip-to-tip distance is to set your telescope up the way you would normally use it then measure the distance between two tripod feet.  Be sure to account for the height the Wheeley Bars will lift your equipment off of the ground.  Compare that measurement with the range shown for each size of Universal Wheeley Bars to match up with the best fit.  Custom Wheeley Bars are available for those that fall outside of all of the listed ranges.  For more information on how to make this measurement, see What is Tip-to-Tip Distance?

If you wish to move your telescope equipment through a doorway, see Doorway Measurements to verify whether you will be able to maneuver your equipment through a particular doorway (based on the size of the Universal Wheeley Bars).

The Medium Size Universal Wheeley Bars are for small, lighter telescopes like a standard C8 that weighs less than 100 pounds.  If you have a telescope with tip-to-tip distance that falls into the Medium range but weighs near or over 100 pounds (total weight of all equipment) you should use the HEAVY DUTY Medium Wheeley Bars since they will support the weight much better.  If you are planning on adding any equipment to your telescope in the future (like cameras, guide scopes, etc.) you should take that weight into consideration.  Heavy Duty Medium, Large and Custom Wheeley Bars can carry up to 300 pounds.  We also carry Extra Large and Max Wheeley Bars for specific very large telescopes.

The standard 2-3/8" wheels work fine if the surface is hard and flat, such as a gymnasium floor or smooth concrete.  If you need to move over concrete with cracks or seams (like sidewalks and driveways) or rough cobblestone-like surfaces, you should get the 5" Wheel Upgrade as these will ride over these surfaces much better without getting stuck.  If moving over grass, dirt or gravel (or you just want a smoother ride) you should use the 10" Pneumatic Wheels.  These wheels will travel over surfaces smoothly and not sink into cracks.  There are times when the 5" wheels can be used on hard dirt, but if the weight of the telescope is more than 100 pounds, the 5" wheels may dig into the upper layer of dirt and become hard to move.  For more information on the composition of the different wheels, see What Size Wheels Should I Purchase?

We do not recommend using Wheeley Bars on any surface under adverse conditions, especially if you have a very heavy telescope.  The heavier the telescope mounted on the Wheeley Bars, the more careful one must be in moving the complete system by pulling or pushing below the center of gravity.  JMI is not responsible for incorrect loading or operation.


Personal Upgrade Path

Buy risk-free: When it’s time to trade up you’ll get the most value for your used gear.