Kinetikx

After about 7000 miles I've finally worn out the 20 tooth cog of the Suntour Pro Compe on my Miyata 610*. In trying to keep the bike fairly original I've been shopping around for a replacement. What I've found is that I can buy a Suntour Winner (New Winner and Winner Pro as well) for not much more money than a Pro Compe, and I really like the ability to change out the cogs.

Here is the question nagging my mind though- If I'm not mistaken the Winner cogs were made of an aluminum alloy correct? Since I've never owned an aluminum cluster before I'm not sure how well they would handle the daily vigorous workout I would give it. Hell, I've broken about 7 teeth off of the steel freewheel (which I blame on the bad roads, but I could just be one hell of a masher ). Would the ability to change out the cogs as I wear them down be practical enough (assuming the supply doesn't dry up) or should I just stick with the Pro Compe and replace the entire unit as necessary?

*The 610 had many more miles before I owned it, and from the story I've heard it even did a cross country tour. So in theory this particular freewheel has quite a few more miles than what I've put it through.

TejanoTrackie 

Actually, the Suntour Winner cogs were available both in aluminum alloy and steel. Steel was more common. However, only the inner splined cogs are interchangeable with Pro Comp. Some New Winner threaded cogs can be used on the outer smaller stage of the Pro Comp. What position is your 20T in? Is it a regular 5-speed or an ultra (narrow) 6-speed? If you switch to New Winner or Winner Pro you can get steel cogs.

Kinetikx

Regular spaced 5 speed. The 20T is the center cog.

And up until now I haven't come across any information about being able to switch out cogs on the Pro Compe. That's a good thing to know and I'm surprised I've gone this long without figuring it out. How would one go about taking it apart? (I'm assuming 2 chain whips to take off one or two of the outer cogs?)

TejanoTrackie 

The Pro Compe 5 speed body has 2 stages. The inner 3 have 4 splines (slots) and the cogs simply slide on/off just like a cassette. The outer 2 (smallest) are threaded, so you have to restrain one of the inner cogs while you unscrew each of the 2 outer cogs. The easiest way to do this is to use a bench vise and a cog holder tool to hold the freewheel by one of its inner sliding cogs and use a chainwhip or track cog tool to unscrew the outer threaded cogs. Needless to say, you remove the outmost cog first before removing the second cog. Since your 20T is in 3rd position it will be splined and any Winner, New Winner, Winner Pro inner 20T cog will fit.

CrankyFranky

Are the splined cogs on the older Suntour "Perfect" the same dimensions as the Pro Compe? My two road bikes both have this freewheel, and they've seen many thousands of miles of miles over the last three decades... but I've run out of unworn steel 19T splined cogs to fit... Does anyone here know where I might find such a unicorn? The alternative is to buy one of these NOS New Winners with what are to me unusable ratios? My current ratio is 15-16-19-25-32 and works well with my 42-52. Don't want to spend hundreds on revamping my drivetrain.

top506

Glad to see you still have (and are riding) the 610. Guess I sent it to a good home.
IIWM, I'd swap out the frewheel for a modern 7-speed. Original is nice, but rideability is better.
Top

bikemore 

I have a box full of Suntour freewheel cogs that I believe will fit pro compe and perfect.
PM me if interested. I think I have a surpluse of 20T and 19T.

Aluminium cogs were meant for race day. I think you would wear them out in pretty short order.
Even 30T front cogs are usually steel. Weight difference isn't much and the wear difference is huge.

JohnDThompson 

IIRC Perfect and Pro-Compe differed only in the color of the cogs.

Kinetikx

TejanoTrackie: I appreciate all of the information. It never fails that I learn something every time I log in here.

Top: Yeah, I've been neglecting my other bikes badly since you sent me the 610. It fits about perfect and for my commute I haven't found anything better. It's been a dream. This is the first problem I've had and can only be attributed to normal wear. Miyata built a nearly bulletproof touring bike with the 610.

Bikemore: I'll take you up on the offer. With this new information it would be silly to spend the kind of money I was considering when I thought that the Pro Compe was a "disposable" freewheel.

Grim

I love what the Suntours looked like but I have to agree. $17 for a complete free hub with ramped gears to make it shift better under power (what broke the teeth) is hard to beat.
https://www.niagaracycle.com/product_...oducts_id=6178

mrmw

From my Miyata 610 1984 I have the original Suntour freewheel. Judging by the original chain that came with the bike, there was something less than 2k miles on the bike when it came to me. I'd love to see the freewheel go to a good home. PM me.

balindamood

I don;t know about where you live, but the bike co-op here has a box full of old freewheels of nearly every description. I have pulled out old Regina's, 8-speeds, alloy, metal. If you have a coop near you, do some digging, you may be able to replentish your supply for the rest of your life for about the price of a single NOS Suntour.

arborohs

take the suntour FW off and put it on a nail in your garage. put on a new shimano FW and never look back. they shift so nice

John E

... assuming he can get the cog sizes he wants. I have stuck with SunTour because I have a great array of spare cogs.

Kinetikx

If only there was a co-op nearby. I'm jealous of those of you who have access to one. We only have 3 bike shops within cycling distance and two of them look at you funny if you come in on anything less than a compact frame aluminum/carbon state-of-the-art machine. And then they tell you they can't help you. One is cooler but they just don't have the stuff I need most of the time.

While I would normally agree with you, I've had absolutely no trouble shifting with what this bike has. And to tell you the truth I've pretty much only had bikes with Shimano drivetrain gear. It's been nice seeing what else the world of obsolete technology has to offer

I've already made a deal with bikemore to get one of his cogs. Thanks for the offer though. If I somehow ruin the whole freewheel when I change out the cog I'll know who to come see Plus I'm kind of looking forward to the experience of partially taking this thing apart.

noglider 

I also have some old cogs that would fit. Let me know if you want me to dig through them.

Yes, the Pro Compe and the Perfect were the same except for color. It was as durable a freewheel as any, but it wasn't special in any way. I agree it provides adequate shifting, but you will find that a Shimano freewheel with twisted teeth will work a bit better.

Alloy freewheel cogs are dumb!