Hey folks,

Getting this really annoying vibration, it's inaudible but you feel it through the wheel. It's the '95 Escort Wagon. at a "certain" speed it kicks in, and it's like badadadum 1 2 3 4 badadadum 1 2 3 4 badadadum 1 2 3 4 badadadum

Repeating at about 5 second intervals... The annoying thing is, if the road is slightly bumpy at all, that overwhelms it and you don't feel it, so it's only on really smooth bits of highway. (Sux for testing)

If I go the same engine RPM (low gear) at a lower speed, I don't get it. If I go the same speed at higher RPM, I don't get it. It doesn't seem to do it under medium or hard acceleration, or if you lift off the gas, it's only steady speed with your foot on the gas maintaining speed or accelerating very slightly.

If I go fast enough (On a private road in Mexico) it goes away.

It seems like it's a beat frequency, and yah, I mathed it out, motor is at about 3100 which is 51ish revs per second, and the tires are rotating 900 times a mile, which works out at about 18ish revs per second, and 3 times that is 56ish, f1-f2 = beat frequency, = 5 ... hmmm

So it seems like tire rotation and engine rpm are getting close enough to make a beat somehow... but at all other speeds, I can't detect enough unusual vibration in either. (Well the 1.9 CVH was never the smoothest motor in teh world evarrrr)

My tires are slightly upsized, put 195/60R14s on it on BMW rims this summer... I'm having a feeling that if I had (a balanced) set of stock size to try that it would not happen. Just the 10 revs/mile difference.

Also wondering if new engine mounts would help... or not, because I'd go for poly and they'd transmit more...

Think I'm gonna try clocking a front wheel 90 degrees tomorrow, just in case that can damp a very faint vibe from them. See if it changes.

Ideas?

RW222