Trainer Shootout – Which Fluid Trainer is the Best?

Fluid Trainer Defined:

Both the CycleOps and Kurt units use fluid based resistance systems. A fluid based trainer is simply defined as any trainer that uses a viscous fluid, like liquid silicone, in the unit to create resistance.

Durability and Resistance Unit Design:

First, the fluid units: While the premise behind the Kurt and CycleOps is very similar, their internal construction is quite different. The CycleOps depends on a thru-shaft that is sealed by an O-ring that keeps the fluid in its reservoir. As the rear unit heats up, friction increases; this can allow any imperfection in balance between the flywheel and the shaft to increase the wear on the O-ring seal. Eventually, the wear could cause the O-ring to wear out and the fluid unit to leak and fail. When this happens is dependent on the speed the rider uses the trainer at and the number of miles it receives – the average will probably be somewhere in the 5000 mile range (3-5 years for a rider who rides the unit regularly). While CycleOps has improved the tolerances and their quality, this is still a potential weak link in their design.

The Kinetic by Kurt uses a well designed and thought out magnetic coupler mechanism to eliminate the highest wear area on the fluid resistance unit – the O-ring fluid seal. In the Kurt resistance unit, there is a completely sealed and independent housing unit that holds the silicone fluid. This unit attaches to the spinning impeller shaft from the rear wheel via twelve magnets (6 on each side). As the impeller rotates off the rear wheel, this magnetic coupler revolves instead of depending on an O-ring seal like most units. This keeps the fluid completely sealed and independent of the rotating impeller shaft.

Durability and Stability of Stand:

Both stands are well constructed. The Kinetic Road Machine unit uses the largest diameter tubing and thus is initially very stable feeling when you install the bike or when you are riding. The CycleOps gets the job done safely, but is not as stable feeling when sprinting or under heavy load as the Kinetic by Kurt.

Bike Securing Mechanism:

All the units use a securing system that is based on rear wheel skewer pressure. The CycleOps unit is the quickest to use as it uses a simple lever that slides until it engages the skewer. However, because the CycleOps is not as stiff as the other two, it does not have as secure a feeling. Kurt uses a threaded engagement system that is big, beefy, and full of machined aluminum (which is no surprise as Kurt’s primary business is in machining for aerospace and medical applications). It is not quite as quick and easy to use as the CycleOps, but it is extremely solid, secure and very stiff. While the CycleOps’ unit seems to work a little better on a wider range of skewers than the other two, none of them work well with the majority of skewers found on bikes today and you should replace your skewer with a basic steel unit (included with both) when using the trainer.

Wattage/Resistance Range:

Both units tested offer plenty of resistance for the vast majority of riders. The Kinectic Road Machine claims to be tested to 3000 watts without thermal failure. and the CycleOps Fluid2 offers tested resistance from 20 watts (about 5 mph) to over 725 watts. This is not to say that the CycleOps cannot work up to the 3000 watts the other companies claim to have tested to, just that they have not released any test data at these speeds. As the wattage increases, so does the heat demands on the unit and testing to 725 watts is a realistic test for most use as your average strong athlete averages between 200 and 250 watts.

For watt junkies that want to put in really heavy duty endurance miles, the Road Machine offers a “Pro” model that triples the weight of the flywheel from the standard 6 lbs to 18 lbs. with an add on flywheel weight. While this makes the trainer significantly heavier and adds to the cost, it also increases spin-up resistance and increases the time it takes for the wheel to spin down to zero again by over three times. This creates huge resistance and additional realism for endurance workouts on slowtwitch muscles.

Ride Quality and Noise:

Both trainers are quieter than the average magnetic or wind unit.

The tolerances that the Kinetic by Kurt units are built to are some of the tightest on the market and their experience in aerospace quality machining shines when it comes to ride quality. Kurt units are consistently balanced and are the smoothest and most progressive fluid unit available and they are also very proven. In our inaugural trainer comparison in 2003 we described the Road Machine as follows: “It holds its speed best and reacts to rider input naturally, allowing the rider to sprint, shift and change position while maintaining speed smoothly.” This is still true today.

While not riding poorly at all, CycleOps Fluid2 trainers seem to vary some in regards to the ride quality from unit to unit. Some seem to be a little rough and others are a bit smoother. We think that this is because of the alignment of the thru-shaft not being perfect on all units. A well aligned and properly functioning standard Fluid2 is the slightly quieter of the two fluid units however and we have seen greater consistency every year with the CycleOps.

Ease of Set Up and Environmental Impact:

The Kinetic by Kurt and the CycleOps require minor assembly that only takes a few minutes. Trainers are not real packaging friendly. We are not a big fan of the styrofoam used by Kinetic by Kurt and the cardboard that CycleOps use seem to work fine and make for a more compact package

Warranty and Country of Origin:

When fluid trainers were first introduced by CycleOps in the mid to late ‘90’s, there were leaking issues that almost destroyed the category and that did lead to CycleOps almost going out of business before being purchased by Saris. Saris saved fluid trainers by solving the majority of the quality issues and the units are far more reliable now. One change Saris made was to offer a lifetime warranty and now both Kinetic by Kurt and Saris are covered for life against manufacturers defects (different from just being “worn out” from use…).

CycleOps is the still made in the USA while the Kinetic by Kurt is now made in China.

Size:

Both units can be folded up compactly and stored easily in a closet or corner. If you are planning on hauling the trainer around with you, the CycleOps Fluid2 is the lightest at 18 lbs. compared to the 23 lbs. of the Kinetic Road Machine. To the Kinetic’s defense, the weight is because it has the beefiest frame tubing and a heavier flywheel - both of which play major roles in why the Road Machine feels so solid and stable.

Price:

The MSRP of the CycleOps Fluid2 is $330, the MSRP of the Kurt Road Machine is $375. We often have additional promotions going that bring the price down further. Call or visit our on-line store’s trainer pages for the latest price.

Options and Accessories:

* Electronics: Kurt Kinetic offers a small electronic head unit that computes power output (+/- 8%) based on the unit’s consistent power curve. This computer works with the CycleOps too.
* Kinetic by Kurt Wheel Adapters and Rock & Roll: Kurt offers an adapter that allows 16-24” wheels to be used in the trainer, an excellent choice for children’s bikes or non-traditional designs. Kurt also offers a unique add on base called “Rock & Roll” that allows for natural side-side motion while training to promote balance and core work.
* Included Extras: Both units include a steel skewer that we highly recommend using and also an introductory training video.
* Tires: Continental is now making a trainer specific tire with a rubber compound designed to minimize noise and maximize wear on trainers. Regardless, we do not recommend using your nice Kevlar race tires…
* Other Accessories: With the Kurt or CycleOps, you will also want to consider getting a front wheel block ($9-$25) so you do not have to use an unstable phone book to keep your wheels reasonably level. A good collection of training videos from Spinervals or CTS ($30-$40 each) helps you stay focused and make the most of your training time inside.

Our Top Pick:

Both of these companies produce a solid product – we would not carry them otherwise.

The CycleOps Fluid 2 started the whole fluid trainer revolution and we give the design a lot of credit for changing the way we all look at trainers and showing just how smooth and progressive a trainer can be. It was the Model T in a world of horse drawn carriages and is a proven performer to this day that has seen many improvements in quality and durability.

We have always really liked the Kinetic Road Machine by Kurt as it is proven, rides smooth and progressively and gives one heck of a workout. The Kurt still has the most stable base and frame design, the closest manufacturing tolerances and it remains the best fluid trainer on the market.

You won’t go wrong with either of these trainers and what works best for you may be determined by how well one unit does in one of the above categories compared to the others. However, if we could only carry one trainer to meet the needs of the most athletes best, the Kinetic Road Machine is still the best of the best because of its proven record of durability and overall performance.

To order a trainer and/or trainer accessories, visit the trainer section of our on-line store