Leesburg Bike Festival- vibrating all the way

[capt.jim]

Just got back from Leesburg today, had a great time. Last week i was compaining of a new vibration after installing a new Toyo and bearings. disassembled everything, Tire was perfectly balanced, bearings like new, the only thing changed was the belt tension. The belt was tight from the factory, much tighter than i thought it needed to be, but i did not check it before disassembly as i had no kriket at that time, but had no vibration at any speed. Now i have vibration from 50 to about 78 where it suddenly smooths out, a steady throttle or full throttle is not bad but under a slight load or moderate roll-on it's very noticable. I pushed on a lot of different belts at the festival, all kinds of bikes and maybe a dozen spyders, all seemed to have very tight belts, i wished i had my kriket with me.I tried from 180 to 280 lbs. and settled on 220 for the ride. It seems that no two spyders are the same, what works for one doesn't work for the other. Do all the other bikes running high belt tension have periodic output bearing failures or is this just a weaklink in the rotax, or is there really a problem at all? I for one am going to tighten mine up a little at a time to see if starts getting back to normal, don't know what else it could be, but loose isn't working for me.

[mike3069]

Way back at the Spyder Homecoming in Valcour I asked one of the BRP engineers at the factory tour a question.

"How critical is the belt tension on the Spyder?"

He said " It is not critical as long as you don't get a vibration in the belt that is bothersome to you." He went on to say that at the recommended (original) setting you could expect to get a small vibration at about 5000 rpm under slight load. I can confirm this as true.

I have been running my belt relatively "loose" since before that conversation mostly because I didn't like the way the wheel would not spin freely with the high tension setting from the factory. It indicated to me there was to much pressure on the drive train bearings, causing excessive amounts of friction (aka high wear) that I hoped to avoid by running with less tension.

So, I backed off on the tension until I got the wheel to roll freely. This turns out to be about 100 -150 lbs on the krikit tool.

How about that?

I now have 25k miles on the bike and no noticeable wear on the rear bearings or front drive sprocket.:doorag:

[Lamonster]

I got to think that your vibration has something to do with what you last worked on. My first guess is the belt but as you've said you've tried everything. I guess it could be your output shaft going bad, there have been quite a few of them on the board these days. :dontknow:

I will say that I've been running lower belt tension than the factory recommended early on. I've seen first hand what too much tension can do to bushings and bearings on my Boss Hoss and that's why I backed mine off. Even after 40K my shaft and sprocket look pretty darn good.

http://www.spyderlovers.com/forums/picture.php?albumid=2&pictureid=6796http://www.spyderlovers.com/forums/picture.php?albumid=2&pictureid=6795

[Trickie Dick]

I've got the same vibration problem. Starts around 50, goes to 65 and goes away. Never had it before my 6000 service. I am running Ride-On so I don't think it's tires out of balance:dontknow:They did adjust the belt and this was the same day the new specs came out so I'm sure they weren't aware of it. I guess I am looking for some kind of confirmation that may be the source of the problem.:chat: Or something else.
Any ideas:helpsmilie: