Derailleur/freewheel for a Miyata 610

[noisey]

I'm trying to replace the 5-cog freewheel (28-tooth max) on my 1980s-vintage bike with something a bit easier on my 1960s-vintage knees. The good folks at IRD have a 6-speed freewheel (14-32) that would seem to provide a good gearing match with the half-step triple crank, but the more I look at things the more I see that could go wrong. Some concerns: Will the Suntour Mountech derailleur currently on the bike handle a 32-tooth cog? If I have to replace the derailleur, must the friction shifters be replaced with index shifters? Will a modern chain suitable for a 6-cog freewheel play nicely with 1980s chain rings? (The rings are in good shape, but are they too thick?) The IRD folks tell me that all their freewheels are made off the same body, so if a 5-speed fits a 6 or 7 speed will also fit.

The bike is perfect for me, I've been riding it consistently all these years, and I'm not at all inclined to replace it. I'll welcome advice from anyone who has done this sort of upgrade.

[GeorgeET]

The Miyota 610 is a nice touring bike.

http://www.miyatacatalogs.com/2007/12/miyata-catalog-1982.html

The friction shifters will work fine. Do you ride a lot in hilly terrain? The middle front and large rear should give you plenty than you can still go to the granny gear. Do not use the large front and the large rear too much crossover.

You may be able to readjust stop screws on rear derailer and use it. The chain would probably be Ok too if you use as recommended above.

Perhaps some gear heads will give you more techy advice.

[Joe_W]

If you are concerned about the dérailleur you can get a low-ish end Shimano MTB our touring RD (Alivio or somesuch). They can accommodate up to 34 teeth (mostly). The chain rings are usually ok for a "modern" 6 speed chain, the inner width of the chain has not changed at all, but for higher speed chains the outer width has been reduced (thinner plates, pins not protruding over the sides as much...). Still, even on my old Peugeot mid 70s road bike (with an old Stronglight crank set) I could use a 9 speed chain without any problems.
So, go ahead (I guess), give it a try! The worst thing that can happen is that you destroy the RD... or bend the dérailleur hanger, now that I think of it, which would be really bad.

[noisey]

Thanks for the insights. From looking at the catalog link, I think the bike is a 1983 model. About the terrain, I'm located in west-central Wisconsin, in the driftless area, and the terrain can be very hilly (see: http://www.horriblyhilly.com/home.html). But I'm no racer, just an avid rider, and the countryside around here is fantastic.

But back to the bike: I've found that I never use the 14t rear cog and rarely use the 16, but I use the 20-24-28 cogs a lot. My granny chainring is 28. The new freewheel still has a 14 but then jumps to 17-20-24-28-32. I'm thinking this will give me more options in the range I tend to use, and help me avoid using the large:large combination with the crossover problems.

Thanks again - and I still welcome comments. This is going to be a winter project, so I have time to study up and get it right.

[nfmisso]

I have changed a couple of 5 speed freewheels to 7 speed freewheel - some times 1 or 2 mm of spacers (I used 10mm ID stainless steel shim washers from McMaster).

With friction shifting you have a lot of options.

A choice that you have not metioned is changing out the crank set so that you end up with a full range of useable gears. Something like this: http://www.amazon.com/Shimano-M131-Crankset-170mm-48/dp/B003ZMDJW6/ref=sr_1_4?s=cycling&ie=UTF8&qid=1353035480&sr=1-4&keywords=48 will provide a lower top gear; making the 14T at the back useable, and closer ratio for our old knees.

My 1960 vintage knees like close ratio gears - the big jump between gears hurts. My riding is much flatter terrain than yours; and I like the 13-23T clusters; with front chainrings to maximize the number of useful gears.

[noisey]

Thanks for your perspective, nfmisso. I understand your feeling re: close gear ratios. The rings on the triple are 52/44/28 teeth and I jump between the top two rings a good deal to keep the ratios close. I figure that with the new freewheel 32t cog and a granny 28t ring I'd be able to climb just about anything I'd find in the Midwest. I also thought that with the 28t cog no longer being the innermost, it would reduce the cross-over stress on the 52/28 combo. So it all *sounds* good - If I can only make all the parts fit!

[nfmisso]

The 610 is a beautiful bike.

There a several routes you could go with it.

1. minor tweaking - which may or may not get you what you want - as we have been discussing above. As noted, I would also replace the RD with a new SORA or TIAGRA triple (aka long cage) - I have had many dealings with CROSSLAKE SALES on ebay - and VERY strongly recommend replacing the chain whenever you swap out a freewheel or cassette.

2. restoration to OEM spec - does not sound like it suits your needs.

3. major upgrades - this is the route that I go with most of my bikes. For my 310 in particular, which was a frame, headset, handle bars, crankset and BB when I got it (the fork was trashed):
* Shimano 36H hubs (low end road)
* 8 speed SRAM cassette (12-23) (should have gone 9 speed)
* Sun CR18 rims (ISO590 to get fender clearance - not an issue with the 610)
* Wheelsmith SS14 spokes
* Kenda 37x590 tires
* Shimano SORA 8 speed brifters (should have gone Microshift)
* Tektro R559 brakes - incredible upgrade in stopping power
* SORA front and rear derailleurs

I am keeping the 52/42 double crankset - no hills to speak of on my commute, I am not fast pedalling, and with a tail wind, I do usually get to use 52-13 combination on my commute with my SR (flat bars). With the drop bars on the 310, I expect to use the 52-12 combo.

If I were doing a 610; I'd keep your current triple crankset; and go with a 9 speed cassette on the rear with new hubs. 130mm OLD will fit with a bit of effort. I would also go with Microshift 9 speed brifters, and a new RD. If the FD is working well, I would not change it.

[Joe_W]

I have Microshift brifters on my cyclocross "frankenbike", they work well enough for me. I tried the Sora STIs (ok, three years ago) on a friend's bike, they are... well... crap. The braking and shifting action is not as well defined as I would like and felt even dangerously spongy. I don't like them and would never recommend them. At all. If you go with Shimano STIs, get at least Tiagra, the group is decent: works well but is heavy (but I guess more expensive than the Microshifts which do work well enough).

A note on the spokes: double butted spokes are the way to go, the resulting wheel will be not as stiff (not really that much of a problem on a 32 spoke or 36 spoke laced cross 3 wheel) but last longer. At least this is what most wheelbuilders write. The reason is that there will be less stress on the spoke elbows (the weak spot) as the thinner middle section of the spokes is more "springy" than a straight gauge spoke.

I have Shimano Tiagra 32 hole hubs on my cyclocross, they need to be repacked regularly (I ride a lot in the mud in winter), but so far seem to work well enough (third winter). The setup is close to what Nigel describes except the rims and tyres have to be more narrow for me (tyres max 30mm due to clearance problems) and I use a Shimano LX? MTB rear dérailleur with a 12-30 SRAM 9 speed cassette and a Campa (low-ish end) road crank set (39-52).

[noisey]

Thanks for all the further replies. I'm leaning towards the "tweaking" solution as I'm very satisfied with the bike, except for it being geared a little too high for my current physical condition. Since I stay on paved roads and don't carry more than 25 lbs of gear (weekends in the the Wisconsin State Park system - something to keep in mind for anyone who enjoys camping by bicycle) when I carry any at all, I don't think I need a full rebuild right now. Long tem plan is to ride this baby until I retire, then reward myself with something new. Only about 10 years to go . . .

[nfmisso]

(11-19-2012, 11:37 AM)noisey Wrote:  ....... Long tem plan is to ride this baby until I retire, then reward myself with something new. Only about 10 years to go . . .

Many of us on this list would be VERY interested in your 610 if you ever decided to sell it. My newest bike is our 1994 Trek T50 tandem (made in Wisconsin ) I would take a classic cr-mo bike frame such as your 610 over almost any current production bike. To get better than it, you are looking at a custom frame.

[GeorgeET]

Yep, 10-4 to that. Some great Japanese bikes were made in the 80's from mid point up. To name some: Panasonic, Fuji, Miyota, Bridgestone , some Schwinn most notably the Super Le Tour made by Panasonic, and others. They were as good as the coveted eyetalian bikes, but affordable.
The new bikes have a lot of fancy gear on them but they are heavy, unless you go into thousands of dollars graphite range. Note weight is no longer given in specs.

Keep your bike, its a good one, just service it well and keep the bearings greased with marine grade grease.The bottom bracket can be refreshed with a sealed BB like the Shimano UN54 if needed and SIS system can be added.............