Whirring sound and some vibration

brianwheelies · Post by **brianwheelies** » Wed Nov 09, 2011 6:53 pm

Ladies and gents,

I am running a 1000rpm contra spring, Prima pipe, and 6g slider weights in my Rattler 50.

At idle it is making a whirring almost squeaking sound and when I am riding it is getting a vibration in the mid 30mph range as the rear pulley does it's engagement to top gear.

The whirring thing has been happening for a while but the vibration just started happening. Any ideas on what would cause these things to happen?

Bike has a little over 1000 miles and run to an indicated top speed of 48mph without difficulty. Revs a bit higher than powerband until it gets to that "high gear of the rear pulley".

viney266 · Post by **viney266** » Wed Nov 09, 2011 7:50 pm

Remove the cover, check for heavy dust or a grove in a pulley ( though I doubt it)

Make sure the nut on the variator is tight

AND, reseat the belt...Pull the front pullies apart so the belt seats all the way down when you reassemble things

Post by **ericalm** » Wed Nov 09, 2011 8:23 pm

How many miles on the belt and sliders?

I've hears a high-pitched whirring coming from a Buddy rider's transmission for some time now. He can't hear it at all for some reason, but every time I ride behind or next to him, it's there are certain speeds. Not sure what it is; all the parts in his transmission are fresh. One possibility is a worn spot on the variator pulley that causes the belt to rub funny and makes a noise.

I kind of what to pull him over, crack open the transmission and just look. On the other hand, I could be having very specific auditory hallucinations.

brianwheelies · Post by **brianwheelies** » Thu Nov 10, 2011 2:09 am

Sliders may have 200 miles. Belt has a little over a thousand miles on it. The vibration is probably the nut on variator needing to be snugged.

The whirring is at idle only and during slower revs. Doesn't seem to be hurting anything but it's an extra noise that has been present for the last 200 or so miles maybe more.

viney266 · Post by **viney266** » Thu Nov 10, 2011 2:18 am

Make sure you get that nut tight, and either "stake" it in place or locktite it...or both. That backing loose is NOT good