Swarup High Performance Combustion Improving Device
Swarup High Performance Combustion Improving Device
EVALUATION
Sekon International Corp. describes the Swarup as a static mixer, a term which brings no meaning to mind, but the advertised claims for the equipment are impressive: "10—20 percent performance to gain, absolutely nothing to lose!" We were told the Swarup(s) would work on any motorcycle engine and the prices, ranging from $28.95 for a Single to $88.95 for a Six, sounded fair if the claimed advantages turned out to be true.
So one of the staff wrote his check for $38.95 and ordered Swarups for a 1981 Honda Hawk. The package arrived two weeks later and contained two gaskets and two stamped metal rings, with mounting flange and with fins facing the ring’s center.
Swarups, according to the company’s literature, improve combustion efficiency by swirling the air-fuel mixture as it moves from carburetor to intake valve. Installation was simple. Unbolt the carb hoses where they mount on the cylinder head and slip the Swarups and gaskets into place. Following the instructions, the units were installed with the fins facing the intake valves and with the two narrow pairs of fins vertical.
In order to ensure accuracy, the Hawk was given a double mileage test. Before the Swarups were installed, the Hawk was ridden on our standard 100-mi. loop, where it returned 63 mpg. Then it went on a second loop, same rider, same distance, same times of day, and this time it did 61 mpg. The Swarups were installed. The third loop, under conditions as nearly identical as daily traffic allows, showed 63 mpg. Then a fourth loop, ditto all conditions, and another 61 mpg.
Tests at the drag strip gave much the same results. With Swarups, the Hawk’s three best quarter-mile runs were 14.98, 15.03 and 15.06 sec., with traps speeds of 85.15, 85.06 and 84.74 mph.
The Swarups were removed and the Hawks’ three best runs in stock condition were 14.86, 14.98 and 15.02 sec., with trap speeds of 85.63, 85.22 and 85.06 mph.
Quarter mile acceleration tests peak power because the motorcycle is run near redline at all times. Although the trap speeds were faster and the elapsed times shorter without the Swarups, indicating a gain in peak power, the differences aren’t enough to be conclusive. We’ll call it a draw.
To measure engine torque at less than peak engine speeds, the on-board computer was hooked up for roll-on tests. To use the fullest range of engine speeds the roll-ons were performed in fifth gear, rather than sixth, so the engine could be run from 3500 rpm to redline by the time the bike reached 80 mph.
Averaging three runs with and without, the Swarup-equipped Hawk went from 30 to 40 mph in 2.3 sec., from 40 to 50 took 2.8 sec., from 50 to 60 took 2.9 sec., from 60 to 70 took 3.5 sec. and from 70 to 80 took 5.5 sec. Pulling out the Swarups, the Hawk averaged times of 2.5, 2.7, 2.9, 3.8 and 5.4 for the same speed changes. The Swarups improved power ever so slightly at a couple of ranges, lost power just as slightly at a couple of others and was a draw at another speed range. Once again, these are remarkably consistent results. No two mileage tests nor drag strip runs nor roll-ons will be exactly the same. If we get figures that are within 5 percent, same day and same rider, on the same machine, we conclude that we have pretty good tests and accurate equipment.
In this evaluation, we also concluded that the Swarups made no measurable difference in performance. Not in speed, not in power, not in fuel efficiency. There may be some validity to the theory that imparting a swirl to the ingoing fuel mixture will create extra atomization, that is, break the fuel into smaller droplets and make them easier to burn. But the fins must also create some degree of blockage, reducing flow through the intake tract. This is a matter of speculation, as we cannot measure either idea and can only guess that if one factor helps, the other cancels it out.
None of the test riders could tell any difference in the Hawk, with or without. This Hawk was the one tested in the January, 1981 issue. It’s gained a few miles per gallon since then, and it’s lost some snap at the drags. But cold starts, warm starts, two-downshift passes and just cruising along with the traffic were the same with Swarups and without.
Put bluntly, we could not find any improvement. We couldn’t find any difference at all. The Swarups have been returned to Sekon International Corp. of America, 2210 Wilshire Blvd., Ste. 557, Santa Monica, Calif. 90403 and our man has asked for his money back.
