clicking from a gearbox

[75vs1885]

Hi,
I am trying to figure out why our chain driven WCP dual speed gearbox is clicking. I am determined it is the chain or the sprocket. We use 35 chain with Vex pro sprockets. I noticed a bit of wiggle when the sprocket is on the hex axle. Also, when the chain come to the sprocket inside the gearbox, the chain is not aligned central to the sprocket. Any advice how to fix this?
Thanks

[DarkRune]

Can you post a picture of where the chain connects to the gearbox?

[R.C.]

Whenever we've had a clicking sound from our drive, it has almost always been bad bearings or busted hex bearings.

A picture would be very helpful here.

[DonRotolo]

A tiny piece of the chain (e.g., master link) may be protruding and contacting something.

[75vs1885]

I am convinced it a bearing too, I'll see if I can get a pic up within a day or two.

[BJT]

I would check the chains. The master links need a little more room than the rest of it. 35 chain gets a little crowded going through there.
There isn't room for 2 #35 sprockets to be next to each other like in the instructions. pretty sure the chains will touch in that situation.

[Mschmeh144]

Your problem may be that your motors are fighting against each other.
It may also be that the gears inside have somehow popped their key out of the slot, our test bed did this because the constant reversing back and forth and rough handling shook it loose.
Was it clicking before, or did it recently start?

[Tim Lehmann4967]

Last year we had a bad bearing that made a clicking noise. Also, it is possible that your chain is not aligned right and a link is jumping a tooth, I would consider this a greater possibility if you are noticing a little shake of the frame with each click.

[mentorDon]

Try using a process of elimination to find where the clicking noise is coming from. First disconnect the chain and run the motor with gears. If the noise has stopped, must be coming from the chain or onward to what ever is connected along with the chain drive.

Second, a long wooden dowel (36 x 1/2") will work wonders at locating noise origins. Hold the dowel up and pressed firmly to your outer ear. By moving the dowel around touching different parts, sounds will increase or decrease depending how close you are to the noise. However you must use some common sense and don't place it between the sprocket and chain or any other place that it can be grabbed.

[Gray Adams]

Originally Posted by DonRotolo

A tiny piece of the chain (e.g., master link) may be protruding and contacting something.

That should be an easy test - what's the frequency of the clicking? That should actually narrow it down quite a bit. The first stage gear reduction is going to have the highest frequency of clicking if that's where it's occurring, and the chain will have the lowest. Simply knowing how fast the motors are spinning and the frequency of the clicking should bring the investigation down to a certain gear or bearing almost immediately.