mrjb

I have a suntour freewheel on an old mountain bike which i decided to rebuild. It was really gritty sounding and no amount of oil seemed to get rid of the debris in side.

I have taken the freewheel off and have degreased it and its come up really well and is ready to be re-assembled.

Does any one have an exploded diagram of suntour freewheels. I belive it is a suntour alpha (thats the symbol on it) it came on a bike which was bought in approximately 1990.

When going to re-assemble the freehweel there seems absolutely no space to replace the ball bearings which came out of it I must be missing something here.. any one have experience of these

HillRider

Rebuilding freewheels is rarely worth the time or effort as new or NOS freewheels are readily available and are fairly low in cost. Shimano still makes a couple of 7-speed freewheels in 11-34 and 14-34 configuration, Sun Race makes 6,7 and 8-speed freewheels and NOS Sun Tour freewheels are still around.

Loose Screws sells Shimano 5, 6 and 7-speed freewheels and Sun Race 7 and 8-speed freewheels at prices from $20 to $50.

mrjb

To be honest I could just go out and buy another bike rather than a new freewheel.. but dont want to. For sentimentel reasons and for personal satisfaction i want to get this back together as is.

If you know of anywhere with exploded daigrams of suntour freewheels please let me know.

mparker326

I don't have a diagram, but which set of bearings are you having trouble with? There should be one set right underneath the ring you used to get into the freewheel and one at the base of the freewheel. Just use some grease to hold both sets in place and a string wrapped around the pawls to hold them in place as your reassemble & you should be good to go.

Have you looked at: https://sheldonbrown.com/freewheels.html

mrjb

mparker326 thanks for the reply. I figured it out this evening. I put the bearings in some degreaser which already had other bearings in, which were slightly smaller. There was quite a few of these slightly larger sized bearings as opposed to the 1/8 bearings in the degreaser. Obviously when i went to put the thing back to gether it wouldnt go with the larger diameter bearings.For some reason i neglected to look closely into the tub full of bearings. Ive now got it back together with the correct bearings..Doh It was very easy.

If any one has a gritty free wheel dont buy a new one! just take it apart clean it, grease it and put it back together.

mparker326

Glad you got it figured out. I just took apart and cleaned a gritty freewheel as well. It works & sounds like new again. It wasn't a big deal and much easier than I expected.

34505838

do you know how many 1/8" bearings were in the freewheel?

JanMM

mrjb hasn't posted on BF in ten years.

34505838

https://www.bikeforums.net/bicycle-m...tory-tips.html

kc0yef 

https://www.bikeforums.net/classic-v...d-reverse.html

bikeman715

+! , I do it all the time . Yes I know everyone said don't and replace , but it not as bad as they makes it out to be .

skillasw

I also have no idea why this is discouraged. I'm not going to replace, for example a Suntour, old Shimano 600 freewheel with a cheap made in china Shimano one. It's easy just like overhauling any bearing system on a bike, only more smaller bearings, that is if you can get the darn thing open.

texaspandj

The Walking Thread.....
I liked the OP 's reply, "To be honest I could just go out and buy another bike rather than a new freewheel.. but dont want to."

I was thinking the same thing. Fixing what you got is so much more satisfying than buying a new replacement.

cny-bikeman

1. Nothing wrong with someone wanting to put the time and effort into doing so, but most of the time simply using solvent instead of oil will successfully rinse out grit, etc.

2. Greasing the pawls, especially too heavily, may result in them sticking at some point.

bikeman715

I agree , If someone have the time and willing to do so why not ? I haven't yet find one than I can not open up and repair .

skillasw

The first two I attempted i just couldn't open I tried and tried, they were left outside for the good part of a decade, so I didn't let it discourage me, I've had no problems since.

Andrew R Stewart 

My first freewheel overhaul was in high school. A hammer and a slotted screwdriver edge served as the threaded race's "tool". After many years of doing this every so often on the many freewheels I've gone through I decided to not care as much and now just use Phil Ten. oil dripped in. Andy

34505838

alright i just did it with 7 speed suntour freewheel from 1989 - it had 40 bearings on the inner side and 31 bearings on the outer side

i followed these instructions https://www.sheldonbrown.com/suntour-freewheel.html (see cover plate issues)

my cover plate kept coming loose like every 3 rides i think because the freewheel rocked slightly back and forth and the rocking motion caused it to come loose first i just tried removing the outer thin washer (like it says) but that made it too tight

so i just dumped out all the bearings on the top, by turning the wheel over and holding the freewheel in place, then i lifted the actual wheel up and off where i could see the 40 bearings on the other side in the freewheel, i dumped those out, cleaned the freewheel -> the pawls are held on by a thin circular wire about 25mm in diameter with a cut in it -> i saw somebody say about holding the pawls in place with a string that might work if the wire is damaged but mine was fine it causes the tension so the pawls rotate out and also holds them in place - and it's intuitive and easy to see which way the pawls go + they have the wear line from the wire - it was .65mm thick 25mm in diameter loop wire with a cut but i don't think it would have to be exactly that - that's the only thing i could imagine going wrong for the freewheel to stop working

but anyway so then i used new bearings 1/8" i put a little bit of grease on the race on the back side to get the balls to stick (i used 41 even though there were only 40 to begin with) - lowered the wheel on to it - turned it over - added the spacers one at a time - then added the dry balls at the top - (i tried adding 32 which i shouldn't have done because i'll explain - maybe it would have worked but i think that was too many i'm sure the original number is enough)

i forgot to mention when re attaching the pawls i put the wire on first and then lifted it up with a small screwdriver and slid the pawls in

so then i used the small screwdriver to add the blue loctite to the freewheel (the threads are sectioned on the 4 tabs) - and tightened down the cover plate really tight - i think it was too many bearings because it was tight but maybe the loctite -

so this is where the problem happened i removed the cover plate (to remove the extra ball bearing) but the spacers came up with it so then the balls all fall down out of place i couldn't get the spacer back on so this is where all my time was spent (1/2 the time) - so when you put the cover plate on with the loctite just do it correctly

so then i did it i really tightened the cover plate back on it doesn't rock anymore at all so i'll see how it goes -hopefully the 41 on the other side will not be a problem - i'm waiting for the loctite to dry - also don't turn it a lot until the loctite dries - but i'll let it dry for 24 + hours

and then pour mineral oil (just because that's what i have) in through the crack see how it goes

i would rate it as easier than hubs but i hate doing everything so hopefully i got it right and can not think about it anymore / but if this works is cool

Andrew R Stewart 

34505838- LockTite on a freewheel cone? There're already hard enough to get loose the next time Over the years everyone I knew of just whacked the stuffing into the tightening of that cone with a skinny punch (or other), I never thought of LockTite. Do let us know how it works out please. Of all the locations to get away with a few less balls then full count the freewheel is it. It's pretty common to have one or more balls less then a tightly packed compliment. I think it has to do with needing the whole body's rotational movement as free/non binding as possible.


So please do get back to us about how your efforts go. I've done a couple dozen+ freewheel rebuilds, if I had to guess, many years ago and I'm always willing to learn. Andy

34505838

__ > everything working i think if you put the bearings on the outer race (which is what i did) rather than the inner race you don't risk putting too many

Andrew R Stewart 

The problem with placing the inward balls on the outer body (the cup) instead of the inner body (the cone) is that when you try to slide the inner body into the outer one the balls are far more easily dislodged by the pawls. To get the count right fill the outer, cup, first then remove that ball count and place them on the inner, cone. Your ball count will be correct (a complete fill less one or two balls) and the reassembly will be less frustrating. Andy

le mans

I haven't gone to that length [yet]

what i do is run degreaser through it at one side, keep spinning it ..add more decreaser untill the grit is flushed through the other side

a freewheel removal tool placed in a vice.. the freewheel slid on, so you can spin it with one hand add solvent with the other

blow it out with compressed air, then go through the same process using oil

WizardOfBoz

There's a nice blog about this topic:
https://restoringvintagebicycles.com...ewheel-part-i/

sch

Threads like this make me wonder if some of these bikes are ever ridden. I can see, maybe relubing a freewheel, but in my experience
from the '70s, freewheels cogs wear out after 5000 or so miles, ie when you change the chain it skips on one or more cogs. Had
6-8 worn out freewheels left over which I finally got around to tossing a few years ago. The blog Wizard of Boz posted was even
more puzzling with discussions of '30s and '40s era freewheels. Must all come off garage queens.

fietsbob

Only the New Winner Pro Body was not something you could not just flush out and re oil from the outside.