Belt vibration at 75 mph - do I need an Idler Pulley/Belt Tensioner?

[pontbrba]

Hi all, I’m hoping to get some constructive feedback regarding belt vibration.
I have a 2020 F3 Limited that I bought new last month. Currently have about 1700 miles.
When my wife and I were coming home from Pensacola on I-10, I started to feel vibration on my floorboards at around 75mph. When I slowed to 72mph, it went away. I thought it might be ruts in the road from blown out tractor trailer tires and the marks the rims leave, but from what I could see the hwy was smooth. Then at times I could d 75mph with no vibration feeling. After about 10 miles I started to notice that while going up an incline and hitting 75mph the vibration reappeared.
The next time this happened at 75mph, I continued to throttle and @ 77mph, the vibration went away.
So with little knowledge I’m surmising that this occurred due to the following reasons.
1) I was riding 2up
2) I was going up an incline
3) the load felt like it was increased due to strong headwinds(it was pretty windy down here in the gulf Coast)

So when we got home, I’m thinking I need a BRP Idler Pulley(belt tensioner).

After researching the forums, I’m getting conflicting reviews on installing one.
My main question is this; does and will the vibration cause any harm/damage to the drive pulley system? Or is it as some have said just an annoyance?
Or should others have suggested, just adjust the tension on the belt to 160lbs?

I love riding my Spyder and my wife loves riding with me. I don’t plan on spending a lot of time on the hwys, but when I do, I want my wife and I to feel and be safe. I’m concerned that the idler pulley is just a item to make me feel happy that the vibration is gone. If the vibration causes my spyders drive system no harm, I’m ok with that. I am concerned that adding a wear item can be more problematic than it’s worth.

Thanks,
Barry

[fjray]

Look around the forum and you will find enough threads about belts and Belt tension to make your eyes bleed from reading them all. Mine vibrated from day one and I could move it around in the speed range but never totally remove it. One of the reasons it lives at a neighbor's house now.

[RICZ]

Here's what I did..........
The factory/shop setting is too tight.
I lifted the rear wheel off the floor, loosened the axle just enough so the adjusters can move it. Using a Krikit II on the midpoint of the belt, I get a reading of 140. Rear wheel back on the floor, the reading should be 150 - 160.
That got rid of 98% of the vibrations. What little come in at 72mph, I can ride around.
Others here have different methods and readings that work for them. There are YouTube videos also. Check them out.
YMMV.

[BLUEKNIGHT911]

Here's what I did..........
The factory/shop setting is too tight.
I lifted the rear wheel off the floor, loosened the axle just enough so the adjusters can move it. Using a Krikit II on the midpoint of the belt, I get a reading of 140. Rear wheel back on the floor, the reading should be 150 - 160.
That got rid of 98% of the vibrations. What little come in at 72mph, I can ride around.
Others here have different methods and readings that work for them. There are YouTube videos also. Check them out.
YMMV.

.... I did the same to my 14 RT after I brought it home to Vermont, and if there is still some vibes I can't feel them ..... Mike

[Mikey]

X3

[RayBJ]

I had the 75 mph vibes until I added the tensioner to my 20 RT. No more vibes!

[Mikey]

I had the 75 mph vibes until I added the tensioner to my 20 RT. No more vibes!

Keep a eye on the bearings in the wheel!!

[fredgal]

same vibration at 70/75 mph, 2020 F3L......... added belt tensioner, no more vibes... i purchased the lamonster one..

[RayBJ]

Keep a eye on the bearings in the wheel!!

I have ~11k mi on the Lamonster rig and have a replacement wheel on the shelf. No sign of wear on the belt or bearings yet.