Jicafold

So I have a 2019 Trek Verve 1 bike. My son's freinds bike. He wants me to sell it for him. It has minimal mileage. I was doing a general tune-up and put a few drops of clean synthetic motor oil in the freewheel. Now it sounds horrible with a grinding sound. It is low mileage. Is this just a lousy freewheel? What should I do now.? Thank you.

Iride01 

When pedaling forward? It must be the chain or something rubbing where it shouldn't. Perhaps if your lube was too thick the pawls aren't engaging fully and they are slipping. Soak the thing in mineral spirits or flush with some lighter WD-40 or other very light lubricant.

When coasting or pedaling backwards? Don't coast or pedal backwards. Seriously.

Some freewheels and free hubs are noisy. If yours was quieter, then perhaps the lube you used washed their thicker lubricant off of the pawls. But that's not really an issue. When coasting there isn't much load on the pawls and it's not a wear issue. Just a noise issue. Consider it a reminder to keep pedaling.

KerryIrons

Assuming that you oiled it in such a way that the oil got into the bearings, your lube simply freed up the grit that was inside the freewheel. Flush it with something (WD-40 is a handy flush agent) until you hear clean clicking, then chase that with some actual oil (motor oil is fine).

Jicafold

Only when coasting. Not pedaling. So it's not the chain, bearings, etc. I took the freewheel off as you can see and it spins rough in my hand.

Jicafold

I'll try this. Thank you.

Kontact 

Phil Wood Tenacious Oil will generally quiet any freewheel.

veganbikes

Agreed with a lot of the above but yes it is also a cheap freewheel but hopefully you can get it maybe a little more quiet.

Iride01 

I can't see that. Did you post a video somewhere?

Any how, when it's in your hand and you are turning it backwards, you probably are going to feel some vibration and roughness.

If it is worse and it feels like there is sand or grit in it, then probably oiling it losened stuff up that was firmly stuck where it wouldn't do any damage. But it might be that you've just never noticed how it works and you are imagining things as bad when they aren't really bad.

Even so, none of what you hear or feel is an issue for when pedaling the bike. Nothing in the freewheel moves while pedaling. Except for the brief moment when you begin to pedal and the pawls engage. As long as they are engaging then I wouldn't worry too much about it. Freewheels are usually inexpensive and you can buy another for the price of some lubes and other stuff you might get to make it quieter.

Jicafold

I have a box of like a dozen used freewheels. For comparison purposes, this one feels the worst by far. I put on a genuine Shimano freewheel and it works well. I was just wondering if I should lubricate this somehow or throw it in the trash. I'll follow the advice from KerryIrons.

maddog34

see that brand name on the freewheel? THAT is the problem.. that is the lowest quality freewheel made, or very close to it. DNR parts are in the competition. and very well named too!...

either find a shimano freewheel or leave that one on and add some THICKER lube like gear oil... Engine oil is loaded with DETERGENT that REMOVED the thin grease that previously protected the bearings and pawls in the C-Star freewheel.. now you are hearing what it actually sounds like when rough garbage rolls across other rough garbage.

drlogik 

Yes, it's a cheap freewheel and agree with other posters, you probably loosened up grit already inside the freewheel hub.

WD-40 may not be the best solution. WD-40 can act like a de-greaser and once inside the freewheel it will be nearly impossible to get it out. Even chasing with Tenacious oil or any other lube, WD-40 will tend to run that lube out of the freewheel hub also. If all you want to do is sell it, then go for it but I would really flood the freewheel hub with WD-40 and try to get as much of the grit out of it as possible.

If you have a compressor, you might try blowing the WD-40 out with that then flood with WD-40 again and follow with gear lube. I agree with a previous post that the detergents in the motor oil helped loosen the grit. Either way, that hub will never be smooth like a new one.

Kontact 

Making a slurry of the dirt and lube inside the freewheel is not going to the dirt out. Put a heavy, sticky oil in it and the grime won't matter.

SurferRosa

Got a hammer and punch? Overhaul it!

soyabean

I always do this with curb finds.

The sound you are hearing is dirt or rust in the tiny bearings.

There are two bearing races, at each visible end of the freewheel.

It would not harm it any further if you were to try more oil. Any excess will run away. It isn't sealed.

The only way to clean out any crap in it is to open it up with a Park Tool SPA-2. First timers should do this over a tupperware container to catch the rain of bearings.

I do them often because it's faster for me to overhaul one than to get a new one from a local supplier.

The only time I use a new freewheel is if the cogs are rusted to the point where it will turn off a buyer.