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performance, but travel is an indicator of how hard you can bOunce, particularly if you're bouncing repeatedly, before your rear suspenders bottom. Below is the measured travel to the nearest eighth of an inch of each shock tested. KONI Boge Arnaco Girling Curnutt Be tors Ceriani S&:W 4 inches 3'14 inches 4 inches 3-3/8 inches 3',4 inches 3 inches 3'12 inches 3- I /8 inches Heavy Another dimension of a shock absorber that we were curious about was the weight when filled with the prescribed amount of damping fluid. Initially, it would seem that the lighter a shock is, the more desirable it would be when you're trying to shave pounds off your. competition or trail bike. However, added metal in the reservoir generally serves as a 'better .heatsink thereby keeping the fluid cooler which, in turn, means the shock will work closer to its designed efficiency longer. This idea falls apart if the metal used retains heat rather than conducting it to the air. Interestingly enough, the shock that gave the best all-around performance (and was one of t~ most expensive) also turned out to be the hea"jest. There were, however, notable differences in weight. The total differences for two shocks (which is how many you're likely to use at a time unless you have. Hakan Andersson's bike) varied up to a little over two pounds, the KONI and the Girling being the extremes in heavy and light weight. More interesting was the weight variation between shocks of the same make that had received the same amount of use. We attrIbuted the weight difference to fluid loss, though the shocks did not, for the most part, leak noticeably. KONI 4 Ib.-4 lb. BOle 3 lb. 8 oz.-3 lb. 8 oz. Amaco 3 1b.-3 lb. Girling 2 lb. 14'12 oz.-2 lb. 14 oz. Curnutt 3 lb. 2 oz.-3 lb. 2'12 oz. Retor 3 lb. 11 oz.-3 lb. 11 oz. Ceriani 3 lb. 7 oz.-3 lb. 8 oz. S&:W 3 lb. 2'14 oz.-3 lb. 2'12 oz. Shocks were weighed with the recommended springs mounted, which is also the way you ride on them. The differences in fluid remaining in each shock after use would indicate that the shocks on e;u:h side of the bike were performing differently. Even a half ounce difference in fluid fill (or loss) tums out to be a significant percentage of the total fluid capacity recommended for most of the shocks tested. Testing Procedures Our original intent when undertaking this project was to have both field test and shock dyno data. Both divisions of the test proved to be more arduous and time consuming than we ever dreamed possible. However, thanks to the folks over at "Cycle" Magazine, a generally accurate if exhausting monthly publication, our task has been lightened. If you desire to see chans and graphs depicting the performance of these shock absorbers on a dyno, you should get hold of a July issue of "Cycle". The field test is a decidely subjective measure. It basically consists oi, "Bow d~s it work?" However, subjectivity does not have significant effect on the importance of the test. It should only cause you to look at the results in light of the methods used to achieve them. Subjective impressions were imposed on a quantified performance matrix so that each tester was forced to justify his choices. We attempted, whenever possible, to keep variables ~o a minimum. The rating was done by two riders of the same weight (within five pounds depending on how the Hollandaise sauce came out on .John's breakfast) and of similar riding styles and skill levels. A particular pair of shocks were mounted on the bike and a rider took off to trav.erse each of the four sections of the testing area. When he felt that he had traveled each section a sufficient number of times to get a grasp on their performance (and enough time for fade to occur if it was going to), he returned to the trUck and the other tester took off without any conversation. While the KONls inspired g;eat confidence over the whooJHle-doos - like you were doing well personally. assigned by each tester were never changed. What you might interpret from- this method is that if our rating numbers agree then our level of validity is probably high. If we're way off in comparative rating, one of us had a personal problem with the shocks. You might have the same problem. Then again, you might.not. In the four categories described previously, we rated the shocks on a scale of one to five. If a shock rated "5 plus" in all categories then the performance of the rear suspension approached that of good fron t forks (since front suspension seems to be at higher state of development than rear) or was the best we would expect from a stock shock. If it rated zero, it equated to the performance of a hardtail - or worse. We rode the stock Yamaha shocks first for a basis of comparison and they would rate around "two" in all categories. In three days' time we ran all the shock absorbers on the bike, making notes of individual peculiarities, and so on. Then, in one day, we ran all of the shocks (in the reverse order) on the bike and rated them numerically. It was something like riding six twenty minute motos each. In the first days of riding, the shocks were' hopefully broken in so that performance might be somewhere near optimum during our numerical rating session. The following is an exact transcription of the notes we made on the final day of testing at Indian Dunes. Though we had thought of printing. exact copies of the scratch pads they are just a bit too difficult to decipher. "Notes" are feelings that don't come out in numbers, that were recorded after individual rating by each tester. KONI-80 series w/S&W 60-90 lb. progressive springs, first position. Tester 1 Tester 2 Whoop-Ce-Doos5 5 MX Chicane5 plus 5 plus Note: the best things that KONls did. So good you have to try it to believe it. Can exit corners very fast with excellent control. Braking on Ripples- 5 5 minus Jump5 5 Note: KONls maybe not as comfortable as some but the most precise, fastest and gave good feedback feel to the rider. You know when to get on the throttle. Unfortunately, Betor's reputation for a short lifespan proved true during our testing. Both shocks seemed to have casting flaws that cracked the eyelets within 30 minutes. They worked pretty well until then. Getting power to the ground in accelerating out of corners was what KONls did best, in fact, better than any other shock tested with Arnacos a close second. Around a fourth gear sweeper foUowed by a jump it was possible to fool them. If you came off the jump still at a lean (to the left), the bike would bounce back once. They refused to fade and the more you run them, the better they work. KONIs definitely take a while to warm up... then performance is outstanding. They make a stock DT-l almost handle. Betor MX model with 60-90 progressive wind spring. Tester 1 Tester 2 Whoop-De-Doos 2 3 minus Note: Smooth at slow speeds but bottomed continually in third and fourth gear. It was impossible to go any faster under control. Straight line stabilitY was OK (rear end didn't come around) but bottoming made the shocks intolerable. They were better than stock DT-1 shocks over whoop-dee-doos only because of their straight line stability. Tester 1 Tester 2 Jump3 4 plus Note: Very smooth landing but feedback for that extra edge in throttle response was Straight line stability over whoop-de-doos was good but Beton bottomed continually. second tester was riding, the first raided the cooler and did his numerical ratings. When the second ,tester returned he did his ratings (sans conversation) and then discussion ensued. We sat around for awhile guzzling this or that and comparing notes. The conversation frequently helped to congeal feelings about the shocks and the field test notes were created. The number ratings lacking. Good contrOl, however, and no kickback. Liked the feel and lack of bounce after landing. But the shocks would bottom from time to time; even then, no severe kickback. Bottoming not good but Betors allow you to leave a jump with excellent control. Seem to give added push for distance. . Tester 1 Tester 2 MX Chicane4 plus 3 plus Note: Would hold on selected line but oscillated in getting power to the ground out of corners. Good precision even over bumps and off-eamber. again until they bottomed out. Ability to 51 ide controllably over ruts very good. Braking o~ Tester 1 Tester 2 Ripples 4 plus 3 plus Note: Action was just average since hobby--horsing was so severe but it was not particularly uncomfortable. Part of it was due to DT-l front end, no doubt. Straight line stability was OK. Wheel stayed on the ground most of the time in braking. The reputation of B"etors for short lifetime was unfortunately confirmed when both of the shocks tested had the top eyelet crack across the entire surface. One of them broke off completely, as shown in the photo.