Tandem Cycling - Burley with Suntour
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.
11-30-08, 06:13 PM
Anybody out there have a Burley Bossa Nova with Suntour components? I am trying to get the lock ring off the rear cassette and having a heck of a time. I have done it before with two chainwhips, but it doesn't want to budge this time. Any hints, thoughts, new curse words, would be greatly appreciated.
Are you spinning it counterclockwise to loosen it? Sheldon Brown's site says you need a special tool to fit the splines, but you have done it before with two chain whips?
Modern Hyperglide (http://sheldonbrown.com/k7.html#hyperglid)-type cassettes (everything made since the late 1980s) us a threaded lockring to hold the sprockets onto the splines (http://sheldonbrown.com/k7.html#gloss_sp-ss.html#spline) of the Freehub body. There is a special splined tool that fits the notched hole in the lockring. Some lockring tools have a long handle, others, as shown below, have a hexagonal fitting like a nut, which can either be turned with a large wrench or may be placed in a vise. The lockring has a normal right-hand thread, turn clockwise to tighten it. When you want to remove the lockring, you need to turn the lockring counterclockwise, but the cassette will freewheel when you do that, so you need a chain whip to hold the cassette from turning.
You can see the 12 spline notches inside the lockring. Lockring tool and chain whip in place, ready to unscrew the lockring.
11-30-08, 09:09 PM
Sheldon Brown's site says you need a special tool to fit the splines, but you have done it before with two chain whips?
Wrong type of cassette... The older they get the more varied they become.
Any hints, thoughts, new curse words, would be greatly appreciated.
There are a couple "tricks" but they all involve a little bit of risk associated with doing a little bit of damage to you or the wheel.
1. The "easiest" and "lowest risk" is to take it to your LBS so that they can skin their knuckles and be put in a position to offer you a good deal or a replacement wheel & cassette if they bugger up yours.
2. The 'might makes right' approach is to slip a pair of 2' steel pipe extensions over your chain whip handles -- assuming they're the older style with narrow handles -- to increase the mechanical leverage. Of course, at this point you'd really want to have a helper to steady the wheel while you work the wrenches.
3. If you think it may be seized by corrosion or some other means you can heat the lockring and then apply some Liquid Wrench and let it soak in for a day before hitting with your chain whips again. The pre-heating helps draw the liquid wrench in as the metal cools.
4. As an alternative to Liquid Wrench, you can use a real wax candle to heat the lock ring a bit -- not so hot that you'd start to do any damage to the freehub's bear seals, etc -- and then turn the candle to a steep downward angle with the wick above the lockring and threads and let the wax drip onto the threads all the way around the lockring. Again, as with the liquid wrench, as the lockring cools the wax will be drawn in and help to lubricate the thread area to help break the lockring loose.
The are some other tricks that involve using canned CO2 to cool then heat parts to help break seized parts loose but, as I said, you can quickly exceed your comfort zone with some of this stuff. Be guided by the mantra: "Do No Harm To Yourself or Your Tandem".
12-01-08, 12:15 AM
I had a similar problem with a Duet and ended up replacing the wheel and cassette. Cold set the rear spacing to 145. Changed the bar end shifter and the RD to XTR 9 speed. All with parts off ebay... Love it!
12-14-08, 03:20 PM
Might won. It took a 4 foot long fence post as a cheater to get it off. I also had to cut the end off the chain whip to get the cheater on. My new question is the freehub has a little give in it if you push it towards the axle (center). Is this normal?
12-15-08, 07:28 AM
If this is the older Suntour where the bottom cog is the lockring I'd be inspecting that real close. On the early 90's XC and XC Pro cassettes, the 11 tooth cog acted as the lockring. However, they were prone to cracking under the pressure. I imagine one of these getups on a tandem would eat cog/lockrings for lunch...
As far as the freehub body goes, I've never seen them to push inward. The Shimano style uses a 10 mm hex bolt to attach the freehub body to the hub shell. Unfortunately, you have to remove the axle to access this bolt, necessitating a hub overhaul. Don't know what the Suntour hubs use but I suspect it's very similar. Or it could be that the bearings inside the freehub body are maladjusted. I'm not talking about the bigger bearings that support the axle, rather there are tiny bearings inside the freehub body itself that allow it to spin freely. These are usually adjusted with a series of very thin shims, and not likely to come out of adjustment unless the lockring (which usually doubles as the axle bearing cups) has loosened up. Not a really difficult adjustment, but not necessarily for the faint of heart, either. This usually requires specialized tools beyond the realm of most home mechanics.
If you're unsure of this you could always take it to your LBS and get their opinion....
Powered by vBulletin® Version 4.1.12 Copyright © 2013 vBulletin Solutions, Inc. All rights reserved.