I installed the DDM 3 ways a few weeks back. Got a louder than usual whine when accelerating in lower gears (my angle drive is one of the noisy ones from day one so I always have a bit of a whine, but this is different). Rechecked ride height and it looks good (did not adjust the rear coil overs per installation instructions during installation). Belt tension appears to be same as prior to installation. My first thought was that i was getting a harmonic frequency whine and hoped that it would go away after driving a few times in case it was just a slight misalignment that needed to work itself out. Took it for a quick errand over the weekend and still hearing it. Any ideas? Anyone else have this happen when replacing coil overs? It isn't a constant noise. Only happens when accelerating quickly through first three gears. If I take it easy on acceleration it doesn't do it and it will also stop if I let up a bit on the gas when accelerating.
DDM 3 Way install - whine under acceleration
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I installed the DDM 3 ways a few weeks back. Got a louder than usual whine when accelerating in lower gears (my angle drive is one of the noisy ones from day one so I always have a bit of a whine, but this is different). Rechecked ride height and it looks good (did not adjust the rear coil overs per installation instructions during installation). Belt tension appears to be same as prior to installation. My first thought was that i was getting a harmonic frequency whine and hoped that it would go away after driving a few times in case it was just a slight misalignment that needed to work itself out. Took it for a quick errand over the weekend and still hearing it. Any ideas? Anyone else have this happen when replacing coil overs? It isn't a constant noise. Only happens when accelerating quickly through first three gears. If I take it easy on acceleration it doesn't do it and it will also stop if I let up a bit on the gas when accelerating
I would check to make sure you are at the same ride height as you were stock, changes in the rear ride height affect the belt tension which can create a noisy belt. When you accelerate in the lower gears you are going to get more weight transfer to the back of the Slingshot, which will lower the back a little more and is probably what is causing the noise. A couple things you could do to check this out would be to raise the compression damping to see if that changes the noise, if so, most likely your rear is a little low for the current belt tension. If that is the case, you can re-adjust your belt to the new ride height or change the ride height to match the belt tension.
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Belt tension appears to be same as prior to installation.
Did you actually measure the belt tension? I forgot to check ride height before replacing the rear shock and the result was initially a loose belt and a squeal just as you described. When temps came up one day above 60 degrees where I was able to adjust the belt back to "correct" deflection, the squeal went away.
Good luck!
Bill
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Did you actually measure the belt tension? I forgot to check ride height before replacing the rear shock and the result was initially a loose belt and a squeal just as you described. When temps came up one day above 60 degrees where I was able to adjust the belt back to "correct" deflection, the squeal went away.
Good luck!
Bill
I didn't closely measure belt tension. I had checked it before when I was worried about it being too tight and that might be contributing to the whine I was hearing from my angle drive. Did a quick check and it felt like it did before I swapped the coil overs, but I was more worried about it being too tight vs too loose. I'll try Dave@DDMWorks recommendation and make some adjustments to see if it gets better. Sounds like it might be too loose under acceleration so I'll tighten it up a bit.
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Also make sure you wash the belt and the sprockets. It sounds crazy... But spray a little of your favorite degreaser on the belt and quickly rinse it off. It will make a huge difference.
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I mentioned this in a post describing my installing our shocks where I thought that a person could use the adjust-ability of the shock to adjust the tension of the belt?
Bill
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I would check to make sure you are at the same ride height as you were stock, changes in the rear ride height affect the belt tension which can create a noisy belt. When you accelerate in the lower gears you are going to get more weight transfer to the back of the Slingshot, which will lower the back a little more and is probably what is causing the noise. A couple things you could do to check this out would be to raise the compression damping to see if that changes the noise, if so, most likely your rear is a little low for the current belt tension. If that is the case, you can re-adjust your belt to the new ride height or change the ride height to match the belt tension.
So got a warmer day today (about 70 degrees right now at lunch time) so bumped the compression up a few more clicks and took it for a drive. Bit of whine at first (garage was still cold), but as soon as it warmed up whine went away. Ride height must have been set just a tad too low with compression set for comfort when accelerating. Will bring ride height up a bit more and that should fix it. Thanks to Dave@DDMWorks and wjfyfe
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I mentioned this in a post describing my installing our shocks where I thought that a person could use the adjust-ability of the shock to adjust the tension of the belt?
Bill
Yep, if I adjusted the 3 ways to the sport settings recommended by DDM there wasn't a whine. At lower comfort levels of compression the whine came back during acceleration or when hitting a bigger bump. Wife liked the smoothness of comfort setting since some of the roads we take are a bit rough in a few spots and I don't really push it when she is along for the ride. Assume that the higher compression kept the back end from moving far enough up to reach the point where the belt got loose enough to whine. I'm going to give it a few more turns with the spanner and hope that I get no whine across the range of adjustability.
