Hi there.

I have a Suntour 6-speed freewheel that's doing something rather strange. I got it used from a friend. When t he freewheel sits overnight it the next day the cogs no longer turn on the body. THe freewheel acts like a 6-speed fixed-gear cluster and does NOT freewheel. I can let oil soak into the innards via the front and the back of the freewheel and shortly thereafter it spins nice and free. BUT... The next day it's back to being stuck and not freewheeling. It's off the bike for this reason. I can really make good use of this freewheel if I can get it to keep its freewheeling ability and not seize up overnight.

Any ideas as to why this is happening?

Also, does the lockring that has the two round indents unscrew counter-clockwise? I have the proper Park pi-spanner for it.

Thanks and cheers

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...the lock ring is left hand threaded, but don't take it apart. There are a ton of tiny bearings in there, and some pawls and springs that have a tendency to fall out.
I think what you have going on is some old, stiff lubricant (probably grease) in there. The oil softens it up so the pawls free up a little, then when you let it sit for a while, it stiffens up again.

Before I took it apart, I would try soaking the whole thing in mineral spirits or acetone for a couple of days. Or flushing it with brake cleaner or another solvent in spray form. Then re-lubricate with oil at the seams where the part of the body that holds the cogs meets the stationary part, front and back. This has always worked well for me. You don't really need new grease in there, because there's no load on the bearings when it spins.

Many freewheels that get taken apart never make it back together.

This. And go from there.

Suntour filed for bankruptcy back in '94, so your freewheel at a minimum has to be older than that. I was taking those apart in the 70's. (trust me, as others have suggested... don't take it apart.) How about replacing it with a new one with the smoother shifting Shimano hyperglide teeth?

If the suggestion above doesn't end up working and you want to chance taking it apart as a last ditch effort, RJ the Bike Guy has a pretty good video on YouTube where he dismantles, cleans and reassembles a freewheel. I can't post links yet, but it should be an easy search.

Or, gather up a couple of freewheels (to make shipping worthwhile) and mail them all to pastorbobnlnh and he'll rebuilt it to NOS standard.

Build-a-long freewheel!!!! Photo heavy

What I wanted to do was loosen the lockring enough to allow any foreign crud inside the freewheel to be flushed out.

I haven't loosened the lockring yet but today I bought a can of WD-40 and gave the freewheel a good soak as I turned t o body once it was unseized. Tomorrow I'll check and see if it's seized again. If it is I'll loosen the lockring and flush the freewheel out again. If that doesn't cure the problem I'll open it up and see if I can flush t he stuff out. If that doesn't work I'll then disassemble the freewheel completely and rebuild it. I've take apart and reassembled many freewheels over the years. It can be done with care and patience. I've always found that the trickiest part is getting the pawls to slip into the notches as the thing is being reassembled and i have a t echnique that make that a lot easier.

Shipping at a post office here in Ontario Canada is based on size or weight which ever is greater and it's not worth it to send a freewheel to the U.S.A. for repair and return.

Right now 6-speed freewheels are very scarce here let alone a quality one.

I have this thread bookmarked and will let you all know how I make out with this.

Thanks and cheers

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...WD-40 is not an adequate solvent for this job. If you really want to take it apart, do it.
But a spray can of brake cleaner from the auto parts store could save you a lot of hassle.

It obviously isn't a "Perfect" freewheel if it is having problems!

I would talk to pastorbobnlnh he runs the Freewheel Spa and specializes in older freewheels if you are dead set on trying to save it.

Me personally I would just get myself a nice IRD Freewheel and be done with it.

The fact that it works “sometimes” means the pawls and balls are probably fine.

1) Use a bunch of solvent that cuts grease. Brakeclean, mineral spirits, acetone, gas, diesel. Work freewheel back and forth. Maybe even submerge it for a while in solvent. You’ll hear the freewheel working again.

2) put synthetic oil in the the seem between the spinning and non spinning parts. Spin and apply spin and apply. Keep doing this until nasty oil comes out the other side. That’s it. Your done. I like synthetic ATF for this type of thing.

I took a freewheel apart once.Never again.

Oh yea... Never use WD40 for this type of thing unless your going to flush the WD40 out. It turns weird and waxy- it’s probably your problem now is WD40.

You'll spend more on stuff to spray in it than just buying a new FW. If you do decide to take it apart, then do it in something that will catch all the little ball bearings and stuff that is inside.

You've been around here long enough to know that eventually someone will have given you this link and you've already looked at it, right?
https://www.sheldonbrown.com/freewheels.html

I thought I had a 6 speed Suntour Perfect sitting on the shelf taking up space but I just checked and it's only a 5 speed..

Yes, I've often read Sheldon Brown's articles. Regarding freewheel cleaning/lubrication he stated:

"First scrape off as much grit and grime as you can, then flush the old lubricant out of the freewheel before relubricating it, To do this, you will need a parts cleaning bath, preferably with a sprayer. Loosening the outer ring by a couple of turns can create a larger gap into which to spray the cleaning solution."

Note that last line:

"Loosening the outer ring by a couple of turns can create a larger gap into which to spray the cleaning solution."

That was the reason I started this thread and asked which way the outer lockring turned to loosen it. I should have revisited that article for the answer. LOL

The freewwheel is working fine at the moment. I'll flush it again with some degreaser and then oil it.

Thanks all and cheers

There is nothing wrong with using WD-40 for this job. It leaves behind a light oil which brake (or carb) cleaner won’t.

...good to hear from you Stewart. Good to know having you on ignore is still the best solution.

Learn how to spell. Often freewheels can be refreshed with light oil. WD-40 contains about 25% light oil. I’m not a huge fan of WD-40 and it can be over used but there are applications on bicycles where it has its uses.

Of course, I’m on ignore so you won’t learn anything.

I’m glad it works for you. I use WD quite a bit at work. I like triflow much better, but WD has the super convenient spray cap that’s easy and fast in an industrial setting.

...you'd be surprised with what a person can learn, with you on ignore. It's quite remarkable.

I don’t seem to be on ignore at all. I thought the whole point of being on ignore was to, well, ignore. You don’t seem to be doing a very good job.

I recommend a thorough soak in kerosene. Loosening the outer “cone” slightly with a pin spanner will allow for flushing some of the crud out the back side. Once the bulk of the hardened grease/crud has been flushed out and the pawls are functioning properly, re-adjust the outer cone to the “Goldilocks” setting (not too tight, not too loose). Since the bearings have little if any weight bearing duty (unlike wheel bearings or headset bearings) serious “greasing” isn’t required. I usually drizzle some Phil’s Tenacious Oil into the bearing races from both the inside and outside.
RE: full disassembly, it has potential for becoming a “mini disaster” but I’ve done it several times with complete success (without even watching a YouTube video) . Count and separate the bearings from the outside and inside races. Be sure to not lose the little springs that push the pawls out (prolly not likely on disassembly due to the thick grease). I’m sure that the suggested references would allow for successful rebuild!

Well folks.

It looks like the flushing with the WD-40 has cured the problem. As of five minutes ago the freewheel is still spinning freely.

I'll dribble a bit of light detergent free oil into the innards to be sure they are lubricated.

Cheers

Try to let the WD-40 dry out a bit by using an air compressor or just let it dribble out a couple of days or more. The WD-40 dilutes the oil. Not a major deal if you don't get it dry but maybe refresh the oil in a month of use or so if their is some WD-40 mixed in.

1/4 of the WD-40 is a light detergent free oil. Just let it dry. No more oil is needed.

Thanks, I'll do that.

Cheers

Thanks but No. I'll put a bit of light oil in there. Many years ago I used WD-40 all be itself to lubricate a freewheel. Later on I had problems with that freewheel and when I opened it up it was full of rust. In my opinion WD-40 by itself is not sufficient lubrication. YMMV but I'm not taking any chances with this freewheel.

Cheers