[220] Resonant Vibration - 7000rpm

Tristik · Post by **Tristik** » Tue Aug 28, 2012 5:12 am

So, I've noticed my blur hits this kind of resonance where the bike vibrates more than usual right around 7k rpms. Below and above that it feels normal. Is this common with the kind of engines in scooters where it has a spot like that? Or is this something that should go away after things are adjusted at my first service this friday?

kenbike · Post by **kenbike** » Tue Aug 28, 2012 10:24 am

Mine had a vibration and extra drive train noise around 5500 to 6000 rpm for the first 250 miles, by 350 it had reduced so maybe yours will smooth out as more are logged in. for sure make a note of it with the dealer at your service. Did you get a quote for the first service from the dealer?

Rush · Post by **Rush** » Tue Aug 28, 2012 2:00 pm

When I first got my Blur I noticed vibrations it at about 55mph. When I first put in my Dr Pulley sliders it changed to about 65mph. Now if I install my windshield as low as possible it shakes at 50mph+. I raise the shield by about an inch and no vibration.

It seems there are many variables that go into the equation. My dealer indicated that all bikes have these vibration points at certain speeds.

Tristik · Post by **Tristik** » Tue Aug 28, 2012 2:05 pm

~~
Kenbike: Yeah, the service guy said around $100, maybe $120 ballpark for the first service.

Rush: Yeah, 7k is right around 55. I can get up to about 50-52 without hitting the vibration point, but have to go past to it/past it to get over that. I only noticed a few days as I hadn't had the bike past 45 or so and I decided to try a 55 mph road.
~~

Edwub · Post by **Edwub** » Tue Aug 28, 2012 4:02 pm

In my first few hundred miles, anything between 3.5 to 4.5k RPM would cause a rattle. After two thousand miles, its somewhere between 5 to 6k RMP. I was worried about it, had contacted the dealer, but saw plenty of posts (such as this thread!) of people with a similar thing.

I'm not too worried about it, although I don't like it. It's just this certain *unsweet* spot that causes it.

Tristik · Post by **Tristik** » Tue Aug 28, 2012 8:59 pm

Edwub wrote:I'm not too worried about it, although I don't like it. It's just this certain *unsweet* spot that causes it.

~~
Yeah, I just wanted to make sure it was normal or at least in a normal range from others' experiences. After it happened a few times I got to thinking about the physics of it and kinda figured a single-cylinder engine would have some kind of sweet spot like that.
~~

chickdr · Post by **chickdr** » Thu Aug 30, 2012 1:46 pm

Yes- mine also has a lot of vibration. I think my old TGB 150 runs a lot smoother. I am kind of surprised how agrarian the engine seems. My Vespa 200GT was butter smooth in comparison. I just had my 500 mile service. It was $105. Seems pricey and I will be doing my own service from now on.

Tristik · Post by **Tristik** » Fri Aug 31, 2012 5:29 am

That first service will vary heavily depending on where you go since it's like 90% labor/inspection. 100 bucks or so doesn't sound bad to me considering they are damn near going over the entire bike