MB33 

I have a 5 speed 14-24 Suntour Perfect freewheel that I overhauled last spring (new bearings and grease and oiled pawls). I used blue loctite on the cone threads and had it adjusted perfectly. I've only put about 500 miles on this bike since then, all easy fair-weather miles. Yesterday it started to drag and I had to play the keep pedaling or die game for the 5 mile ride home. I haven't taken it apart yet but was curious as to what the freewheel experts on here say. When you spin it by hand some revolutions feel good but then it'll start to get hard to turn and then easy again. The only thing I can think of is the loctite failed and the cone got slighty tighter. But I thought because of how it's orientated in the drivetrain when the cone slips it will loosen the freewheel, not make it tighter.
Any advice would be appreciated.

pastorbobnlnh 

I doubt the Blue Loctite caused the issue. Also, I've never serviced a Perfect or ProCompe freewheel that I couldn't use a hammer and punch to make the final tightening. The factory shims have always been properly spaced.

I'd be more inclined to think a bearing or pawl failed, or so sort of debris has infiltrated the interior. You'll need to open it and see what is the cause. Take pictures.

steelbikeguy

Can you explain how you adjusted the cone?
SunTour used shims to properly space the cone on the Perfects (and most other models of freewheels), making adjustment unnecessary. All that is needed is to tighten the cone.

The blue loctite isn't a bad idea, though, since the cones did sometimes come loose and allow the bearings to jump to freedom.

Steve in Peoria
(had two instances of escaping freewheel bearings on Perfects)

MB33 

When reassembling I used a hammer and punch to turn the cone until there was no play. If you go too tight it binds just like any other cup/cone bearing. i reused the shims.

steelbikeguy

With the disclaimer that it's been decades since I took apart a Perfect or ProCompe, this doesn't seem right. My recollection is that the shims were selected to allow the cone to be tightened fully without the bearings getting tight. There's no provision for a locknut to jam against the cone to maintain an adjustment, so anything other than fully tight seems unlikely to keep the adjustment.

Threadlock compound does seem like the best stopgap measure, I suppose. Might be time to try the red instead of the blue? ... although if you do, the cone will never move again.
The best solution is to find the correct thickness shim(s), but the odds of that seem slim.

What do Pastor Bob and the other Perfect fans think?

Steve in Peoria
(but I did have to adjust a New Winner a few years back when it started getting loose)

pastorbobnlnh 

Another, but I'd guess a very slim possibility, could be that a thin spacer became damaged in reassembly and eventually worked a portion of itself into the bearing race (at the place you feel the binding). However, with that said, the Suntour spacers on Perfect and ProCompe freewheels tend to be very robust. They are unlike the very thin spacers Shimano used on their freewheels which can be thinner than aluminum foil and are very easily damaged.

As a rule, after I clean and service a freewheel, I try to stack the thinest shims between thicker ones with the hope this provides better protection to the delicate ones.

Circling back to the ProCompe and Perfect models: They all have a two-tabbed spacer (fits into the removal notches). This one should be installed first. Set aside the thickest spacer to install last. Place the thin spacer(s) between the two-tabbed and the thick spacer.

I wish I had a better picture, but this shows a Perfect/ProCompe and the two-tabbed spacer and only one additional spacer. Generally, these models only use 2-3 spacers.

Prowler 

^^^^^^^. I have found that the thin spacers can be foil thin, less than paper thin. So like Bob says, I install them first with the thickest spacer on top. When we drive the outer “cone” down tight there could be enough friction to smear a foil spacer, even into the ball track as Bob mentioned. Having overhauled several Suntour FWs too, I agree with our good, albeit retired Pastor (suffering mightily all year long on the Georgia coast, a tear rolls down my cheek).

dddd

I have more than once had one of a freewheel's bearing balls break in half, which caused the sort of symptoms that the OP described exactly.

But, as Bob mentioned, the debris might come from one of the other parts, a pawl for instance.

Do not use Red Loctite on the cone threads! You'll need a torch to get it apart later.

Drillium Dude 

Whoah! For real? Never have I ever heard of a ball bearing breaking in half. Now I'm curious as to what that would actually look like! Did the damaged ball score the races?

Since BBs are relatively cheap to replace, I hope for the OP's sake this is the issue. And, if it is, I hope to see pics of this rare occurrence.

DD

bulgie 

In the early-'80s I was making fancy expensive boutique custom frames, with tandems a particular specialty. We settled on the Suntour Tandem FW (similar to a Perfect or Pro-Compe IIRC) as the best, don't remember why, but probably thicker/stronger pawls? Unless it was just marketing hype. pastorbobnlnh will know...

Anyway, they were even more prone to unscrewing and spilling their guts than regular Suntours. And you couldn't just tighten the ring further, because it would bind the bearing. So we had to remove the ring, add a thin shim and re-tighten super tight, after a quick de-grease of the threads and some blue loctite. Sometimes the bearing would still bind after adding a shim, and we'd have to open it back up and add another. We did this on every Suntour FW before putting it on one of our custom bikes. None of them ever came loose later, as far as I know, but with the addded labor, it made for a pretty expensive FW.

For the source of Suntour freewheel shims, at first we cannibalized old dead FWs, but eventually we were able to order a bag of 100 or whatever from Suntour.

That scenario was all too common even with the regular single-bike Suntours — needing one more shim to allow you to tighten it properly. Why we put up with that cr@p, I don't remember; I guess all the other options available to us had different issues. Suntour sending all those FWs out into the world missing a shim is close to criminal negligence. Saved them a nickel maybe, but it caused quite a bit of grief and anguish for the victims.

I remember rerassembling a Suntour by the side of the Pacific Crest Trail (back when MTBs were legal on that trail), trying to find as many balls as we could in the grass and dirt, and using sunscreen as "grease" to hold the balls in a row while reassembling. A rock and a screwdriver as hammer and punch to seat the ring — it worked! I forget whose bike, probably not mine since I knew all too well about Suntours, from shimming and loctiting them at work.

Someone, I forget who, figured out that leather boot laces make decent bearings, just cut a length of rawhide lace the length that goes once around and fills up the space where the balls should be. The balls aren't very important, they're under very little load, you just want to keep the inner and outer parts of the body in alignment so the pawls engage right. Surprised that leather would be rigid enough but the report I heard said it worked so well they didn't even replace the FW when they got home. They just forgot about it, and it kept working. Maybe you have to get lucky and have boot laces that are close to 5/32" in cross-section. Or 1/8" or whatever FW balls are, I forget now. Plus, who even uses leather boot laces anymore?

OK children, enough tales from bygone eras!

Mark B

pastorbobnlnh 

1/8" ball bearings, as best I know, are universal to all freewheels, regardless of make or model.

Leather shoe laces!?! Amazing!

pastorbobnlnh 

Let me also add that I've encountered broken bearings and broken pawls when servicing freewheels.

The bad bearings I suspect were low-grade, corroded ones, which had experienced harsh conditions such as salt and moisture exposure.

This is the primary reason I use Super Lube synthetic grease in the races. Super Lube is very, moisture, salt, and temperature resistant. It also sets up a nice barrio at the gaps between the bodies (spoke side) and the outer body and the retaining ring/bearing race (frame side), which helps keep contaminants on the outside and from infiltrating the interior.

The few broken pawls I've encountered (had on last week) have, IIRC, primarily been newer model Regina BX, CX, America, Syncro, models. I also seem to remember a Sachs Aris pawl breaking in the past. Never to the best of my memory do I recall a broken Suntour or Shimano pawl breaking. The type I've seen break have been the ones held by the single circular compression spring.

My guess as to why the Regina and Sachs pawls broke is that those pawls are smaller and less robust than Shimano or Suntour pawls of similar design.

MB33 

Update, I overhauled it yesterday and took it for a 10 mile ride and it ran fine. Sorry, no pics. There really wasn't anything to see. It was just a bit dirty, no loose metal and no damaged bearings.
This was my first freewheel overhaul and I think I went too sparingly on the grease (I was worried about gunking up the pawls and getting grease on the cone threads) so there wasn't a good barrier to prevent anything from getting in. I used more this time around.
Thanks for the help all!

pastorbobnlnh 

MB33, Glad it was just road grime and nothing serious. Good job.

merziac

In my world, freewheels are the only thing I ever degenerate shortcut, I usually use Marvel Mystery to flush then 50wt to evaluate, many/most straighten right out and go for years after this.

Had a run of crunchy ones a couple of months ago when I was building and swapping some around, all but one came around just fine and have been going good. The bad one was never going to come back and I now have several that are ready to rock when needed instead of futzing to see if a random good one will work from here on.

Please forgive me Pastor.