Bicycle Mechanics - Upgrading to cassette hub, new shifters, reusing rim?
Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.
As a fall/winter project, I'm going to be upgrading my new-to-me-this-year-but-probably-from-about-1990 Bianchi Sport SX to semi-modern standards, mainly because freewheels are getting hard to come by and close-ratio freewheels are no longer made. It's currently set up with stock Shimano 105 components (13-24 freewheel, 50/42 Biopace crankset) and very spiffy looking 36/32h Araya rims. I bought it used, but I reckon the bike has about 2000 km on it. I have upgraded the shifters to Rivendell Silver bar ends, but I still have the stock 105 downtubes.
I will be buying a new 36h 105 rear hub, and having a wheel built.
-is there any reason not to re-use the spiffy-looking rim?
-should I select the spoke gauge based on what was used originally?
-with kilometrage that low, could I save money by re-using the spokes (?!? - I know this isn't supposed to be done...)?
-are new 105 hubs still the same old Shimano cup-and-cone loose-bearing type (which I think are lovely)?
Also, I suspect having more gears will make me want indexing, even though the Silvers work just fine for now. I am planning on buying a Dura Ace 9sp downtube shifter set and mounting them on the Rivendell bar end pods using the flat lever boss covers for the 9sp Dura Ace bar ends (which I got online from a store in the UK). (I would prefer not to use DA bar end shifters -- I prefer the look and feel of straight, shiny shifters.)
-are all Shimano lever boss covers the same, other than being curved differently?
-are there any other possible problems with Shimano DT shifters as bar ends?
-does anyone sell flat lever boss covers for narrow steel-tubed frames which I could use to mount my Silver Shifters on another bike?
This was rather a lot of questions. Thanks for your help, Mechanics Forum People!
(and, if anyone wants my 6sp 105 shifters or hub, I'm happy to let them go)
There are a couple of reasons why spokes generally aren't reused, some commercial, some "practical":
- if you are going to charge someone for the job, it's nice to keep your customers satisfied. Since there's really no way to tell how much life there's left in a set of used spokes it's difficult to know if you're giving the customer a reliable wheel.
- hubs, spokes and rims go together. Unless you're replacing with same make/model, you have to hunt down a part with the same measurements. If you don't know one offhand, the search time may end up costing more than what a set of spokes would.
- Disassemble and reuse takes longer than scrapping and relacing. Even if they haven't seized, old nipples/spokes will be harder to turn than shiny bits.
Rims are a bit simpler. A good shop may actually have a tool to measure brake track wear, and barring that there's at least a chance of a decent guesstimate. But there's still the question of the overall condition of the rim. When the wheel comes apart, will the rim still be round and true? If it isn't, will the customer still be happy with the result of the work that he has payed for?
I've certainly built wheels out of used spokes as well as used rims and hubs. But that has been on my time and my use, with only me to blame for getting stranded along the road.
While it's entirely possible to build a perfectly decent 9-speed wheel with straight gauge spokes I prefer not to.
1.5 mm gauge NDS and 1.8 mm gauge DS gives a rather nice spoke tension balance. But 1.5 mm require a tad more attention during building. Some compromise between ease of build and spoke tension balance by doing 1.8 NDS and 2.0 DS.
I'd like to build a 2.3 DS/1.8 NDS wheel some time, to see if I'd notice any difference.
In total, anything but a hub reuse probably requires that the wheel builder is either quite irresponsible, or that you know him/her really well. When there's trust you can get things done that are out of the ordinary.
10-14-11, 08:10 AM
can you post some pics? here in the US the Sport SX ended in '89. the only 105 components I see on a Sport SX are the shifters on a '85 but that came with Suntour derailleurs.
10-14-11, 08:57 AM
As a fall/winter project, I'm going to be upgrading my new-to-me-this-year-but-probably-from-about-1990 Bianchi Sport SX to semi-modern standards, mainly because freewheels are getting hard to come by and close-ratio freewheels are no longer made.
Moving to 9 speed will be a huge improvement from your current 6 speed set up but if your real reason for switching is the availability of freewheels, you might be surprised what you can still get. Sunrace makes a 13-25 7 speed freewheel for $15: http://www.universalcycles.com/shopping/product_details.php?id=31292&category=1665
Interloc appears to offer close ratio (13-24) freewheels in 6 and 7 speed variants here: http://store.interlocracing.com/fr76and5sp.html
Bianchigirl: I'll get a pic and serial number when I'm next home. I had never heard of a 105 Sport SX either. It came with indexed 6-speed 105, with beefy single pivot calipers (silvery grey, not the blueish anodized ones) which might date it a bit better -- I think that rules out '85. I don't think anything has been changed out because it came with 105 pedals, headset, hubs, and so on. Could this be some Canadian oddity?
A friend now has the frame from my slightly-too-small '87, which had Suntour Alpha 5000 (beautiful stuff). (I bought two mothballed Sport SXs within a few months of each other, from Kijiji.)
Joejack: I live in Winnipeg, which has no natural hills and less than 100' elevation change within the city. Interloc's $50 (+ shipping to Canada) freewheels don't do much better than my 6sp 13-24 (13-15-17-19-21-24). I do long, spirited group rides in the flat plain around here, and would like closer ratios at the high end. A 12t would be nice for tailwindy days as well. If someone made a 13-19 7sp freewheel I'd be all over it, but my only option there is ludicrously expensive non-Hyperglide Regina or Sachs from eBay. The reason I'm considering re-using parts of the wheel with a new 105 hub is so my rims will match -- I can't find any modern rims that looks similar.
10-14-11, 11:40 AM
Joejack: I live in Winnipeg, which has no natural hills and less than 100' elevation change within the city. Interloc's $50 (+ shipping to Canada) freewheels don't do much better than my 6sp 13-24 (13-15-17-19-21-24). I do long, spirited group rides in the flat plain around here, and would like closer ratios at the high end. A 12t would be nice for tailwindy days as well. If someone made a 13-19 7sp freewheel I'd be all over it, but my only option there is ludicrously expensive non-Hyperglide Regina or Sachs from eBay.
Ok, I didn't realize you meant that tight of a ratio. An Ultegra 6500 9 speed 12/21 cassette (http://www.universalcycles.com/shopping/product_details.php?id=4548&category=40) sounds like your next buy.
10-14-11, 11:51 AM
Oddly, changing a hub and reusing the rim and spokes is more likely to work than any other substitution. Except for a few specialty hubs (track, high flange, etc.) most standard road hubs have very similar flange diameters and spoke hole circle diameters.
I once replaced a late '80's 6/7-speed Maillard freewheel hub with an 8/9-speed Shimano Acera freehub using the same rim and spokes to get a compatible wheel for use on my indoor trainer bike. The hub swap was a drop-in fit and the old spokes were the perfect length.
Assuming your rim and spokes are low-kilometerage (is that a word?) and haven't been abused or badly abraded, the hub change should be both feasible and a good idea.
I'll give it a try, then. At worst, I'm out some spokes and need to buy new ones. I've put perhaps 1500 km on the wheels since I bought the bike, and the previous owners had it in storage since the early '90s; I don't think it was ridden very much. Everything is in very good shape.
Thanks (joejack) for pointing out a still-available Ultegra 9. I've also looked at at a Tiagra or SRAM 12-23, which would be about the best spacing/range balance for my riding.
10-14-11, 12:07 PM
HillRider, I have a 1985 Trek 660 with a Helicomatic rear hub that I've been thinking of simply replacing rather than scrapping the whole wheel. I haven't checked dimensions but had been assuming I'd need new spokes. Sounds like there's a chance of dropping in a Shimano rear hub. If so that might finally get me to move on doing something with that bike that's been hanging in the garage for over a year now.
10-14-11, 12:23 PM
I really like those 6 speed 105 shifters. I'm doing a similar upgrade to yours by building new wheels (since I've never done it before thought I'd do both and do the supposedly easier front as practice - also have it complicated by needing to have 26" wheels with 130 mm hubs), but I'm planning on staying with my 105 shifters in friction mode for now. I decided to go with Kelly Take Off's (http://www.kellybike.com/2nd_xtra_takeoff.html):
as a way of mounting my shifters to make them more accessible rather than on the downtube. So far it's a setup that's worked really well for me. Others might correct me on this, but it might be better to go with am 8 speed cassette if you're staying with your current crankset from a 6 speed (though that does get back to potentially limiting your cassette choices a bit again). If you did decide to go with 8 speeds vs 9, don't get the currently made shimano 8 speed indexed dt shifters as they have no friction option and I'm a big fan of the friction option when something or other has bumped your RD out of whack (in my case being left on the rack while I'm at work and somebody next to you isn't careful with your bike) and you just want to get home before trying to adjust it. I suppose even if you did get the 9 speed dura ace dt shifters (which do allow friction), you could use the indexed if you use the alternate routing of the cable and set your limit screws carefully.
New (9/10 speed) DA works the same as everything else Shimano. It's just the old 6-8 speed stuff that was weird, as far as I know. I'll probably stick with the Silver shifters (as bar ends) for a while -- they beat any other friction shifter I've used. A friction option is a must for me as well.
I will need to look into the crankset issue. I would really like to keep the funny Biopace rings.
(Also, considering re-mounting the Silvers on Paul Thumbies or something like that for my 9sp mountain bike, because I'm tired of having to re-adjust the indexed trigger shifters that never work properly.)
Powered by vBulletin® Version 4.1.12 Copyright © 2013 vBulletin Solutions, Inc. All rights reserved.