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GL1800 Viper Shake Solved!!!
I had my trike conversion done at the end of August last year. The conversion was done quite a distance from home and I stayed in town until it was done. The conversion took 2 days and was done on a Thursday and Friday. Friday night it was ready and I was staying another night because it would have been too late to head out. I rode it around town and started getting used to it. I left town Saturday morning and had some back roads to travel before reaching the highway. Once on the highway, I noticed that just over 60mph, I would sometimes get a pretty bad shake. If I sped up to 70 or higher it would go away. It didn't do this all the time and I couldn't figure out what was causing it.
I didn't have any shaking before the conversion. I did call the builder right away and he asked if I could stop in the shop before my trip home. Unfortunately, I had a 600+ mile trip home and had to be there by the evening before my wife went to work. I just figured that it might be coming from my front tire which was a Bridgestone G709. Not the best front tire for a trike. The next day, I went out and started looking the trike over. The trike came with Ohtsu FP6000 205/55R16 rear tires. I had never heard of them before. I did notice the right rear tire only had about 3 stick-on weights and the left had a string of 7 or 8. I had a bulk bag of dynabeads so I decided to add those to the rear tires. I already had them in the front. I added 4oz in each rear. I still had the shake. Next I ended up removing the stick-on weights but still had the shake. I had a new BT45 that I had been planning on using for the front once I wore out the G709 but went ahead and had a local shop swap out the tires. I still had the shake.
I added 1 more ounce of dynabeads in the rear tires and still had the shake. I also tried playing with various tire pressures on both the front and the back. The shake wouldn't happen all the time but when it did happen, it was pretty bad. I would just try to ride faster or slower so I didn't have to deal with it. I had planned to try and get back down to the builder to see if it could be solved but ran out of riding time last year and had a pretty eventful spring this year so I didn't get a lot of riding in.
Fast forward to Labor Day weekend. I had a road trip down to Eureka Springs Arkansas with my brother in law for an annual gathering. Before the trip, I added 2 more ounces of dynabeads in the rear tires thinking that it might fix the problem. It didn't and I was still experiencing the occasional shake. On the way back home, I knew that I was going to be going past Litchfield, IL which is the home of Niehaus Cycle, which is a well known trike builder for California Sidecar.
I had talked with my brother in law during the trip about what was happening so prior to getting to town, he rode on my right while I was going around 64mph. He actually saw the right tire bouncing off the pavement and then stop bouncing. He then switched and rode on my left and saw the left tire do the same thing. We got to town late in the afternoon on Monday, Labor Day and stopped for the night. First thing Tuesday morning, we went to Niehaus where I was met by Brian Niehaus. I explained everything that was going on and what I had already tried. He said the first thing to do was to pull the rear tires, remove the dynabeads and balance the rear tires again. After doing this, they had me take it out to see if it was any better. It wasn't. He said the tech, Rocky who has been involved with trikes for many,many years was convinced that it was probably the front tire causing this and highly suggested that I install a new Michelin Pilot Activ.
Because I had already experienced this with 2 different front tires, I was a little skeptical but it was logically the next step to take. I had them do it. It did make a dramatic difference but there was still some shaking there. It was getting late in the day and I had another 3 1/2 hours of driving to go so I made plans to bring it back to them in 2 weeks when I could leave it with them for a while to investigate further. This was a lot closer than going back to the original builder. I knew about the earlier issues with the Cobra driveshaft but everyone told me that the Viper was almost bulletproof and had not had any of that. I was also concerned that it might be a problem with the half shafts.
The next day, I ended up reaching out to tech support at CSC and spoke to Shawn. I explained the problem to him along with all my attempts and what Niehaus had done. He was very helpful in listening and then related that he had a similar experience with one of their other trikes. He said he went through almost the exact thing that I did and tried just about everything. What finally solved it was by changing out the rear tires and all but guaranteed that if I did that, the problem would go away. He said that he was going to cover it as a warrantee item and give me an allowance to go to a local tire place and get new tires.
I ended up at a local NTB and went with Goodyear Eagle RS-A tires. Not the most expensive, nor the cheapest but all the cheaper ones were brands I was unfamiliar with. I finally got a chance to try them out tonight. Well I am happy to say that the problem seems to finally be gone. I took it out on the highway and finally no shaking at 60mph+. Another thing that I had previously noticed was that when going right, I had no issues but left was another story. Whether it was sweepers, twisties, or hairpin turns, quite often the trike would feel very unstable and felt like it wanted to tip over. A completely different feel than with right turns. Tonight, whether it was left or right, the trike felt more planted and like it was on rails. With these new tires, it was a much more enjoyable ride. It had a much more comfortable ride overall as well.
So a big thumbs up to Shawn and to California Sidecar for helping me out in solving my issue.
