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ebubar
06-05-2013, 10:22 AM
I broke a spoke on my rear wheel coming home from work Monday. Noticed it when cleaning the bike for a Tuesday ride.
Its a 32 spoke wheel, so i'm pretty sure I can bike the 2 miles to a LBS and get it fixed tomorrow.

The fun question is if I should try this myself instead? I have the spoke. I know how to loop it through and thread it into the nipple.
I think I could get the wheel balanced again by eye (I have all day tomorrow to do it). The only problem is the rear cassette is in the
way so I need to remove that.

Since i'm turning into a full-time bike commuter, learning to work on my
bike is probably pretty useful and slowly accumulating the necessary tools would be wise.

Looks like i'd need to buy:
A cassette removal tool (recommendations?), a chain whip (recommendations?) and a big honkin' adjustable wrench.

Seeing how nasty my rear cassette got in the rain on Monday (Georgetown Branch made me feel like a cyclocross racer!) I suspect I'll be removing and
cleaning the cassette a few times a year. Would the bike gurus on here recommend me trying such a fix myself?

More expensive than having the LBS do it (I suspect), but over the long haul (say replacing more spokes in the future and
being able to remove the cassette for cleaning myself) it would be cheaper.

Dirt
06-05-2013, 10:40 AM
On the rear wheel, you'll probably need to remove the cogs and chain whip, as you said. If you're not going to be doing this often, I'd suggest going as inexpensive as possible. Many shops have a Park tool stand and you can just find what you need there. A shop jock can help you find the right stuff.

Removing and cleaning the cogs is a great thing to do yourself. It isn't difficult and it pays dividends in better shifting.

When it comes to threading the spoke, look carefully at how the broken one is threaded in. You'll need to put the new one in using the same pattern. The spokes cross and weave between each other. Most common pattern on 32 spoke wheels is what they call 3-cross. That means each spoke crosses three other spokes (on the same side of the wheel) between the hub and the rim. The spoke will go over two, then under one before getting to the nipple.

You'll need to get the correct length replacement spoke. It is good to buy a few spares if you're the kind of person who saves things. There are numerous spoke calculators on-line. I've been using Pro Wheel Builder's calculator with good results lately: http://www.prowheelbuilder.com/spokelengthcalculator/

One more thing when you're doing this... when you take the cogs off, look carefully at the spokes behind them. If you've dropped the chain off the top of the cogs a few times, you'll see that these spokes get quite chewed up. If they are chewed up and your spoke broke here, then you'll really need to have the whole wheel rebuilt. It is only a matter of time before more spokes break.

One more, one more thing: (I lied about the last "one more thing" comment): Once you've replaced the spoke and tightened it up similar to what the others around it, you're still going to need to true the wheel. Just replacing a spoke will not completely make the wheel true. The act of a spoke breaking impacts every other spoke on the wheel and it takes at least a little effort to get it all straight again. There are good how2s for wheel truing out there.... Lennard Zinn's books are pretty good. I think Sheldon Brown (MHRIP) has good info on the process. Lots of folks love Jobst Brandt's bicycle wheel book.

ljksdfoui

Sorry. That was Mao! helping me type.

Truing the wheel can be done using the brakes as guides, but a truing stand really does the job right.

Okay, I think that covers most of it. Let me know how else I can help.

Pete

DismalScientist
06-05-2013, 10:42 AM
Sure, you should try it yourself. What's the worse thing that could happen?:rolleyes: (You can always bring the results of your "repairs" to the LBS.

If you can do this, you can also replace the chain and cassette when that time comes.

Brand names don't matter when it comes to cassette removal tools and chain whips. I would suggest a box wrench that fits your cassette removal tool. You will need a spoke wrench as well. You might as well get the chain tool as well.

Use the brake pads as a guide when truing the wheel after replacing the spoke--no need for a truing jig.

jabberwocky
06-05-2013, 10:42 AM
Would the bike gurus on here recommend me trying such a fix myself?Sure. Removing and installing a cassette is dead simple. I like the Park tools, but you don't need to be ultra picky. You need a lockring tool, a chainwhip and a wrench to turn the lockring with.

Replacing the spoke isn't complicated either, though it requires a little more finesse to get the wheel true (though losing one spoke on a 32 spoke wheel probably didn't throw the wheel too out of wack). Remove cassette, thread the spoke through paying attention to how it should go (under or over the other spokes). Thread it into the nipple. Tighten the nipple with a spoke wrench. Once it has some tension, check the trueness; the amount of tension in the spoke will pull the rim to the side it angles towards.

ebubar
06-05-2013, 11:14 AM
You've inspired me to give it a go. Perhaps I can get to the bike shop tonight before close and get everything I need.
Drive my wife insane by working on my bike in the late evening hours!

rcannon100
06-05-2013, 11:26 AM
If this is your first time doing this stuff, consider going to a bike COOP - using their stuff, and getting "help" from the staff. I went to Velocity when I was having trouble with my derailer. They were GREAT!!! If there is a COOP near by, it might be a good alternative to buying all these tools.

Jason B
06-05-2013, 11:30 AM
too bad you're not on this side, I'd tell you to head over to VeloCity Bike Co-op in Del Rey. They would let you use the tools and walk you through the entire process for a small donation. Heck, they probably have a used spoke for a nickel. Takoma is pretty hippy, isn't there a similar bike cooperative over there?
Also, when you take off that cassette, zip tie the whole thing. Can't tell you how many spacers I've lost!

hozn
06-05-2013, 11:44 AM
The zip tie is a great suggestion. The only other thing that I'd add is some emphasis on making small adjustments to spoke nipples -- like 1/4 turns then evaluate the effect. The "worst thing that can happen" here is that you could bend your rim out of shape by over-zealous tightening at which point you will need a lot more than a new spoke. (I figure it's worth a mention, because this happened to my sister a few years back when she decided to replace a spoke and didn't quite realize that truing wheels is best approached with restraint.)

jopamora
06-05-2013, 11:54 AM
Take thee to the Bike House (https://maps.google.com/maps?saddr=takoma+park,+md&daddr=1240+Upshur+St+NW,+Washington,+DC+20011&hl=en&ll=38.951399,-77.012873&spn=0.040783,0.07493&sll=38.962564,-77.017863&sspn=0.081554,0.14986&geocode=FWDBUgIdjPVo-yk7N5J0Aca3iTHgIU1G74e9CA%3BFYgzUgIdSqZo-ym3mcgAFMi3iTGVKZ7lCw089A&gl=us&dirflg=b&mra=ltm&t=m&z=14&lci=bike) on Saturday at noon.

Bilsko
06-05-2013, 12:36 PM
to add to your purchase list:
New rim tape for when you're all done with spoke replacement and truing
--Advice from a guy who's only ever taped a rim once, ever. (Extra 'ever' for emphasis.)

baiskeli
06-05-2013, 01:16 PM
Just to add:

The cassette remover depends on the type of cassette. They aren't all the same. Remember to get one to match.

The cassette side will have different spoke length than the others, so don't forget that when you shop. The other side on the rear tire may be a different length than the front ones too, for future reference.

krazygl00
06-05-2013, 01:27 PM
The zip tie is a great suggestion. The only other thing that I'd add is some emphasis on making small adjustments to spoke nipples -- like 1/4 turns then evaluate the effect. The "worst thing that can happen" here is that you could bend your rim out of shape by over-zealous tightening at which point you will need a lot more than a new spoke. (I figure it's worth a mention, because this happened to my sister a few years back when she decided to replace a spoke and didn't quite realize that truing wheels is best approached with restraint.)

Yep. In truing, "less is more". In this case what you should do is pretty straightforward. Tighten the new spoke very small amounts until the wheel approaches true, then stop. Don't touch any other spokes, just get the wheel to a shop where they can do a final truing. Also, be sure to mark the new spoke with electrical tape or something. If you want it done properly, the new spoke needs to be pre-tensioned just as the other spokes are, then re-trued and finally the wheel probably ought to have a good going-over with a tensiometer.


to add to your purchase list:
New rim tape for when you're all done with spoke replacement and truing
--Advice from a guy who's only ever taped a rim once, ever. (Extra 'ever' for emphasis.)

Rim tape is totally re-useable! I've done this countless times. As long as it sticks well enough to get the tire and tube on and there are no holes you're good to go. I've even transplanted old rim tape from a retired wheel to a new one (provided the width was the same).

jabberwocky
06-05-2013, 01:31 PM
I can generally replace a spoke without having to remove the rim tape (or even the tire), as long as the old spoke is still there and the nipple hasn't fallen into the rim. Just be careful removing the old spoke remnant and threading the new one on.

ebubar
06-05-2013, 02:11 PM
I've got pictures of the spoke so I can rethread it correctly. I suspect the following should be good for cassette removal: http://www.parktool.com/product/cassette-lockring-tool-fr-5

Its a stock trek 7.2 fx so the cassette is shimano branded as far as I know. Seems like a regular old chain whip should work fine too (http://www.parktool.com/product/sprocket-remover-chain-whip-sr-1).

I imagine (perhaps wrongly) that a pretty standard stock bike should use more or less standard stock tools. If I knew enough to have something fancier, then I would probably know of any
special or "fancy" tools that I needed.

If I try to hitup the LBS tonight after departing metro (without a bike in hand), can I just tell them "I need a cassette removal tool for a Shimano rear cassette and a chain whip" and they
should know what i'm talking about?

Then over to Ace hardware for a long adjustable wrench (i'm imagining I'll need a goodly amount of torque) and I should be good to go!

krazygl00
06-05-2013, 02:19 PM
Then over to Ace hardware for a long adjustable wrench (i'm imagining I'll need a goodly amount of torque) and I should be good to go!

If you have a bench-mounted vice you should be able to forgo the large wrench. Drop the lockring tool into the vice, attach the chain whip to the cassette, then drop the cassette onto the lockring tool and remove. Installation is easy; you just use the wheel to torque the lockring back on.

baiskeli
06-05-2013, 02:58 PM
If I try to hitup the LBS tonight after departing metro (without a bike in hand), can I just tell them "I need a cassette removal tool for a Shimano rear cassette and a chain whip" and they should know what i'm talking about?

Not quite. This article shows several cassette tool types, including two different Shimano types.

http://www.parktool.com/blog/repair-help/cassette-and-freewheel-removal (scroll down)

One of them is probably more common though - perhaps common enough to just buy it and try it. The shop may know.

The article above should be useful to you in general too.

jabberwocky
06-05-2013, 03:03 PM
Not quite. This article shows several cassette tool types, including two different Shimano types.99.9% of bikes sold today use the shimano splined freehubs, which uses the tool ebubar linked earlier (park FR-5).

Just tell them you have a modern bike with a shimano freehub and they'll point you at what you need.

baiskeli
06-05-2013, 06:01 PM
99.9% of bikes sold today use the shimano splined freehubs, which uses the tool ebubar linked earlier (park FR-5).

Just tell them you have a modern bike with a shimano freehub and they'll point you at what you need.

Awesome, thanks. Looks like you're set, ebubar.

Dirt
06-06-2013, 05:54 AM
Then over to Ace hardware for a long adjustable wrench (i'm imagining I'll need a goodly amount of torque) and I should be good to go!
It shouldn't take very much torque to get the cassette lock ring off. You REALLY don't want to use a lot of torque to put it back on. Most of the lock rings have torque specifications on them these days and they're not very high.

DismalScientist
06-06-2013, 08:09 AM
99.9% of bikes sold today use the shimano splined freehubs, which uses the tool ebubar linked earlier (park FR-5).

Just tell them you have a modern bike with a shimano freehub and they'll point you at what you need.

I think my old freewheel tool (FR-1) might work as well. I love how component manufacturers slightly change their specs so one can buy multiple tools.

ebubar
06-06-2013, 05:42 PM
$30 and 1 hour later and bike is good as new with a new spoke. Shifting smoother than ever after the nice rear cassette cleaning!