I have a 1990's Team Miyata, and am looking at upgrading the cassette from a 7 speed to a 9 speed. What I am wondering is, is it possible? Secondly, if it's not possible could I still upgrade to an 8 speed?

A 7-speed freehub body is too narrow to accept an 8,9 or 10-speed cassette all of which fit the same freehub body. So you would need either a new rear wheel or a replacement freehub body. Also, your frame's rear dropouts are most likely spaced 126 mm while 8-speed and above are 130 mm so you would either have to "cold set" (read bend) the dropouts wider or struggle with every wheel removal and installation.

Thanks for the info, I need to replace the rear wheel anyway since it is poking the tube with the spokes and punctured 3 of my good tubes, but it's unfortunate that I can't upgrade without a lot of modifications.

Well, if you have to replace the rear wheel anyway, get an 8/9/10-speed one and spread the frame or struggle slightly during wheel changes. It's not that bad. Of course, if you go to 9 or 10-speed you will need new shifters, a new chain and possibly a new front derailleur.

If you want to keep it 7-speed, get an 8/9/10-speed wheel anyway and the 4.5 mm spacer needed with a 7-speed cassette.

The front derailleur needs to be replaced as well anyway because it does not have enough travel.

Sounds like that's just a rim tape issue? But I'm not one to try to talk someone out of an upgrade...

Really?

+1

Or MAYBE - on a single-wall rim - something that'll need the attention of some sort of grinding tool - Dremel, rat-tail file, angle grinder... - before receiving a new rim strip.

Once when it wasn't the time to do something noisy, I used hotglue to cap each protruding spoke before installing the rim strip. Worked fine for as long as I had that bike. A bit of soap on the finger allows you to pat the hotglue into shape w/o burning before it sets.

Quite unlikely.

Have you replaced the BB?

Done a triple-to-double conversion?

Check the limit screws and the cable pull.

If you have Shimano hubs you might be able to replace the 7 speed body with an 8 speed and fiddle with the axle spaces to stay with 126mm. But you would need to change the dish on the wheel (the rim wouldn't be in the middle of the frame because the wider freehub would change the spacing) . You could get your LBS to this and grind the end off the long spokes as well.

Thanks again guys, I have tried to repair the rear wheel using wheel tape (it origionally had a plastic lining which made it really easy to spot the bad spots), but the tire still went flat again. I think it could be the patch on the tube because of the repair I did, and because they are very old patches from the late 90's. As for the front derailleur whenever I go into 1, 1 it makes that metal on metal sound because it hits the chain. The hub is Campagnolo sooo... I do not think it's had a triple-to-double, but it might have had a BB replaced since the bike was origionally shimano, but was converted to Campagnolo.

And don't let the 126 to 130 spacing scare you on a steel bike. Lots of guys in the C&V forum do this without issue. I have an old Raleigh with a 130mm 10 speed hub and I can get the wheel in and out with just a slight pull on the stays.

1. Adding more cogs does not necessarily add more utility. It may primarily only add smaller cogs (higher gears) than you have now. On an older bike that may have a 52 tooth chainring that is of little value

2. Adding more rear cogs will be costly - 9 speed will require chain, , wheel, cassette and brifters and possibly derailleur

3. As noted above spokes that are too long can be ground down, but irrelevant if you decide to replace the wheel for the upgrade.

4. Look up "chainline" and check to see if your chainwheels are in the proper place. Replacing the derailleur may be the wrong solution.

I assume it's a steel frame. If so, I had an early '80's Miyata 7 speed and upgraded it to 9 speed simply by changing the rear wheel. It was a little snug but worked fine.

You don't have to "cold-set" the frame to slip a 130mm 8,9,10 spaced rear wheel into your frame. All that is required (if at all), is slight outward/spread with your fingers when installing a 130mm rear wheel.

Have you/did you try adjusting the travel limiting screws on the front derailleur? Sounds to me like at least one travel limiter screw is not adjusted correctly (travel limiter screws keep the front derailleur from traveling too far inward (on the small chain ring), and too far outward (on the big chain ring).

Converting to 8, 9, 10, speeds on the rear wheel will require a replacement rear wheel (8, 9, 10 speed rear wheels use a same size freehub, change to one of these will require a new wheel), shifters (buy shifters to match the number of speeds on the rear wheel), rear cassette (buy to match shifters), and probably a chain (8-speeds uses a chain with the same size links as 7-speeds, but the length required may be different, 9, and 10 speeds use different chains with different size links, and switching will require a new chain).


You may need to replace the crankset (if changing to 9 or 10 speeds), as the distance between the chain rings is narrower on 9 and 10 speeds, and the new 9 or 10 speed chain may fall/jam in the space between the chain rings.

You might also need to replace/upgrade the shift housings and inner cables to get shifting to work properly.

The change to 8 speeds in the rear is simpler, because the chain link size is the same as 7-speeds, and the derailleurs, and crankset will still work. Only parts that you need are the shifters, rear cassette, and a rear wheel, OR a replacement freehub body for the rear wheel, if the existing rear wheel with take a longer freehub. Since you are having problems with your rear wheel, and need to replace it anyway, this would be a perfect time to change/upgrade to 8-speeds, since it is a minimal change at minimal cost.

Look on your local Craigslist for shifters and a set of rear wheels, or for a bike being parted out that you could take what you need from.

If you are getting a rear wheel anyway, go ahead and make the switch to 9 spd - and don't look back - you will love it!

Going from a 7 speed to an 8/9/10 speed hub body (Shimano) opens up a lot more in the way of available cassettes and is not that hard to do, a steel frame will cold set from 126 to 130 with little to no problem.

I have done this on countless bikes.

My daughters 7 speed mtb is now a 9 speed, my vintage road bike now runs modern Ultegra, and many a nice 7 speed cassette wheel has been turned into an 8 or 9 speed wheel with a new hub body to give them continued use with newer components.