Grinding noise from vibrating sander

Sounds like a defective relay even though that should not take hours to cool and work again, same for a main breaker.

Sounds like you need new engine mounts

It sounds like you're in need of a pump and probably a new hydraulic piston for your rack.

the motor is not working anymore.. send for servicing.

I would think that if the noise was being made by your transmission, it would start whenever you put the transmission in second gear and continue until you shifted to another gear, not at 19 mph only.

This sounds like a vibration that is specific to the engine rpm at that speed. It may sound like a grind but may actually be a vibration noise. Try to recreate the noise with the bike sitting still in neutral. Be careful not to allow the engine to overheat though.

Try other things to help you narrow down the source of the sound. When it starts, gently touch the brakes while maintaining the speed to try to eliminate the brakes. Does the noise change if you accellerated slightly or back off the throttle slightly.

It's very unusual for a transmission to make a noise in only one gear. I've found that if a transmission is making a noise, it makes the noise all the time but maybe louder at some speeds than others.

Good Luck
Steve

A grinding from the hub sounds like a bad wheel bearing.

It may be the transmission input shaft bushing or bearing, located in the rear of the engine crankshaft, in front of the clutch assembly. If the bushing or bearing is dry (needs to be greased), the input shaft will still try to turn with the engine rpm, even though the clutch pedal is depressed. Also, the clutch disc may not be fully releasing, which could possibly be corrected by adjusting the clutch pedal linkage. good luck

Try soaking the inside down with some wd40.It wont bother the electrical components but it might loosen up the motor.

blower motors on its way out dont wait till friday call some one tomorrow older belt drive units may have bearings going out in reality any furnace thats still out there with belt drive even thermo couple equipment has served its life cycle and should consider being replaced if it contains either or both ofthe for mentioned components

Sounds like a bad roller. You'll have to remove the drum to get at them. Even a free one may make noise at speed. Use high temp grease. Also check roundness. And don't forget the belt tensioner roller, just don't get any grease where the belt touches.