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-   -   Hints and tricks thread (http://www.bikeforums.net/bicycle-mechanics/316561-hints-tricks-thread.html)

HillRider 08-22-07 07:58 PM

Quote:

Originally Posted by rmfnla (Post 5125070)
A rotating shaft (pedal axle, BB spindle) exhibits orbital motion in the direction opposite to its rotation.

Could you explain this further? How does a shaft turning between two sets of bearings orbit?

Quote:

Originally Posted by rmfnla (Post 5125070)
If the balls are generating enough friction to affect a properly tightened pedal or BB someone needs to learn how to adjust bearings.

The balls are rotating counter to the direction of the spindle. The bottom of each ball where it contacts the spindle moves in the direction of the spindle causing the top of the ball where it contacts the outer race (bb cup or cartridge shell) to turn in the opposite diredtion and, in effect, tend to tighten the cup if the threads are pitched correctly. Of course the friction isn't much but it isn't zero either.

p4nh4ndle 08-22-07 08:59 PM

Have a cup of coffee while you're setting up to do a repair.
Have a beer if said repair isn't going well.

Tat2Art 08-22-07 08:59 PM

Quote:

Originally Posted by wroomwroomoops (Post 4778038)
I thought it would be a good thing to have a thread where people post and discuss little tricks they came up, during the course of their cycling and bike-repair experience.

One trick I have: I noticed that, no matter how good the rubber insulation on the battery lid of the cyclecomputer, in the Finnish wintery rains, at least a tiny little bit of water will make its way in, and cause a little bit of condensate inside. That might be just a cosmetic problem, or it could drain your battery's life, depending on the amount and place of condensation. This is even much more pronounced with bike lights, where the water can find much larger "holes" on the lid (much longer edge), and the insulation is usually worse than with cyclecomputers.

My solution is to put a little bit of lithium grease on the strategic places. Lithium grease is hydro-repellant and very stable. Together with the existing insulation, it will provide nearly 100% security against water infiltrations. Try to avoid getting it on the contacts with the cradle, even though it's not critical.

Great thread. I used to spray some Krylon Fixative or Clear Coat around my spark plug cables in an old car I had that seemed to attract moisture when it rained. This might also work in your case.

rmfnla 08-23-07 10:51 AM

Quote:

Originally Posted by HillRider (Post 5125711)
Could you explain this further? How does a shaft turning between two sets of bearings orbit?


The balls are rotating counter to the direction of the spindle. The bottom of each ball where it contacts the spindle moves in the direction of the spindle causing the top of the ball where it contacts the outer race (bb cup or cartridge shell) to turn in the opposite diredtion and, in effect, tend to tighten the cup if the threads are pitched correctly. Of course the friction isn't much but it isn't zero either.

The ends of the shaft experience orbital force against the direction of rotation. It's a physics phenomenon that I remember from the old engineering days, but it's been too long for me to rememebr the terminology or I would just Google it for a clear explanation. I'll keep trying and if I find it I'll ressurect this post.

Agreed, it's not zero; my not-too-clear point was that it shouldn't be enough to loosen a properly tightened cup.

redirekib 08-23-07 05:21 PM

Always remove the cap from the valve stem before attempting to add argon...I mean air.

wroomwroomoops 08-23-07 11:34 PM

Sometimes, when you have a flat and are not too far from home, you might be able to inflate the tire and cycle for a few kilometers, then reinflate it again etc. until you get back, and fix the tube in a more cosy environment.

Related to this, check also this and this post.

And if you have a gear hub and/or rollerbrake, check this.

Wordbiker 08-24-07 05:00 AM

Never fix things that aren't broken the night before an event...they're guaranteed to break and the LBS is closed.

redirekib 08-24-07 06:32 AM

Tubes with holes in them have a tendency to leak.

bkaapcke 08-24-07 10:26 AM

Never forget that bikes are really simple machines. Derailleur adjustment is a little bit of voodoo, but anyone can learn it. BB removal and replacement requires extreme care and cleanliness to avoid damaging very shallow threads. Beyond that, everything is easy. bk

wroomwroomoops 08-27-07 10:10 AM

Adjusting the chainline on a FG or singlespeed bike - and you don't have the right BB width. Now, of course, you can play around with the dishing of the rear wheel (remember that you have also to move around the spacers on the rear wheel's axle, or else you didn't really "get it" how redishing the rear wheel is supposed to change the chainline), but there's a better way, if your chainline is off by only a few mm: spacers on the chainring bolts.

And not only that: if you have a road crank, you don't necessarily have to put your chainring in the outer position - remember, there's the inner position, too. So you can put the chainring there thus moving the chainline closer to the bike's central symmetry plane.


A straight chainline is critical. Just one mm away from the perfect straight parallel can mean a falling chain, and I don't have to tell you how annoying and even dangerous that can be.

wroomwroomoops 08-27-07 10:19 AM

Oh, and related to chainring bolts: can't tension some of the bolts properly, because they are slipping? Clean with a degreaser or with alcohol the affected surfaces to remove any trace of grease or oil. Often that's all you need to do, but if it's not enough, apply a little bit of acetate glue - actually, I found that any paper glue will work fine, including wheat starch glue (if you can even find such anymore (I'm passionate about antique book conservation, so I have my sources...)). Wait till it dries a bit before tightening the chainring bolt.

NOTE: You apply the glue to the surfaces of the bolts that face the chainring, not the threads.

bkaapcke 08-27-07 04:54 PM

If your derailleur is out of sorts, and you are going to go through an adjustment sequence, always do this first. Run the chain down to the smallest cog. Check for slack in the shifter wire at the derailleur. If there is slack, loosen the pinch bolt and pull it out. Retighten, and you are ready to do your adjustments. bk

Wordbiker 08-27-07 06:57 PM

Buy a fresh set of hex wrenches every once in a while. Much cheaper than stripped bolts and extractor kits.

joejack951 08-27-07 07:12 PM

Quote:

Originally Posted by Wordbiker (Post 5156847)
Buy a fresh set of hex wrenches every once in a while. Much cheaper than stripped bolts and extractor kits.

Or use a grinder/dremel tool to remove the worn out tip exposing fresh hex stock underneath. Just don't overheat hex key while doing this. This will extend their life by at least 3X.

One other hex wrench tip: not all hex wrenches are created equally. Cheaper tools are much softer and are much more likely to round out hex recesses while rounding the corners of the tool at the same time. Quality hex keys are a good investment to make.

Tat2Art 08-27-07 08:47 PM

I know there are a lot of uses for old/worn out/too many holes inner tubes but the other day I was out of patches and so I thought about it and determined to give it a shot. I cut out a piece of "old" inner tube, cleaned it along with the spot where there was a hole with rubbing alcohol then buttered (put rubber cement) on both pieces. The place where the hole was in the inner tube and the cut piece of inner tube. So far so good. No problems for over two weeks now, so it doesn't look like I'll be buying any "patches" in the near future.

Wordbiker 08-27-07 10:36 PM

Carry a $5 bill when you ride.

It will buy some food if you bonk hard.
It will boot a torn tire sidewall.
It is enough to bribe someone in a car for gas money if you break down, and is better than carrying a $10 or $20 as they are guaranteed to "not have change".
You aren't likely to find an impulse buy along your route that a $5 bill will cover, sparing you spending it.

DMF 08-30-07 09:21 AM

To remove a square-taper crank, the full procedure:

When you screw in the puller, be sure that the "plunger" - the inner screw - doesn't bottom on the axle before the outer screw bottoms in its hole. If it does, it will feel like the puller is all the way in, but it may not have more than a few threads.

When pulling square-taper cranks:
  • Visually inspect the crank, checking that there isn't a washer in the hole or parts of the dust cap still in the crank threads.
  • Always screw the plunger all the way out before inserting the puller.
  • Don't use a wrench to set the puller in the crank unless necessary. If you can't get it in with your fingers, then something is wrong (usually, the threads are damaged). You can use the wrench when you think it's finally all the way in to be sure it isn't hung up, or to force it past damaged threads but be sure it's not crossthreading.
  • Count the number of turns the puller makes when inserting it. That will tell you how many threads are engaged. Anything less than about 6 and you're taking a risk.
  • If the plunger is tight and the crank doesn't want to come off, tap the end of the plunger with a metal hammer a couple times. The vibrations should cause the crank to loosen. It may pop loose, or loosen just a bit. If it doesn't pop loose, try turning the plunger again to take up any new slack and repeat.

llalagen 09-10-07 08:31 PM

instead of trying to rub talc,cocoa,baby powder,... or whatever onto your tube,... put the talc in a plastic bag with the tube and act as if you were getting ready to bake the tube and shake it. this will get the entire tube covered very quickly.

torque specs can always be related to bottles of beer placed on the the end of a 12 inch wrench

when installing a tube make sure that the valve is in the middle of the largest label on the side of the tire... "it looks professional and will help you to locate the source of flats" - the art of wheelbuilding

before you build a wheel read Zinn's The Art of Wheelbuilding

stop working on other peoples bikes if you don't want to work on your own anymore

don't spend all of your time on this website reading about bikes, get your @$$ in the saddle and ride!

wroomwroomoops 09-12-07 12:21 AM

Quote:

Originally Posted by llalagen (Post 5246043)
before you build a wheel read Zinn's The Art of Wheelbuilding


I try not to reply to posts in this thread, but I feel this one time I'll make an ecception: it's not at all a mandatory requirement to (buy and) read that book. Sheldon Brown's article on wheelbuilding is detailed and will enable anyone to build rock-solid 1st class wheels.

I have followed his instructions, and all my wheels are bombproof and true.

greywolf 09-16-07 01:53 AM

Use old spoke nipples as cable ends , just slide the nipple over the cable end, shank end first, squease the nipple shank with the wire cutting jaws of a pair of pliers (gently) to fix to the cable then nip off the head of the nipple with the wire cutters.

wroomwroomoops 09-16-07 06:47 AM

Quote:

Originally Posted by greywolf (Post 5277386)
Use old spoke nipples as cable ends , just slide the nipple over the cable end, shank end first, squease the nipple shank with the wire cutting jaws of a pair of pliers (gently) to fix to the cable then nip off the head of the nipple with the wire cutters.

This seems like an eccellent hint, thanks! Will it work just as well with nickel-plated brass nipples, or only aluminum? Brass nipples might be a bit too burly for the wire cutters.

greywolf 09-22-07 11:33 PM

[QUOTE=wroomwroomoops;5277707]This seems like an eccellent hint, thanks! Will it work just as well with nickel-plated brass nipples, or only aluminum? Brass nipples might be a bit too burly for the wire cutters.[/QU
I,ve only used the normal n.p. brass nipples , the wire cutters on an ordinary pair of pliers are more than adequate for the job.

lancekagar 10-01-07 12:15 PM

The following information shouldn't be divulged to anyone outside of this very small circle of forum members.

Ride your bike to a thrift store and head for the women's section. Find the rack with the exercise clothes and start browsing. Amongst the leotards and fluorescent track suits, you'll find decent cycling gear there (for women and men). Jerseys, cycling shorts, and even rain gear, often of good quality and condition. I guess the people that organize clothing at thrift stores don't recognize the value of these items and misplace them.

Not that there's a whole lot of difference anyway. A lot of that stuff in the women's "athletic" section are made from the exactly same materials as expensive brand-name cycling gear, and usually half the price.

Analog 10-06-07 11:46 AM

If you have a bent derailleur hanger, find and old, worthless hub axle with the same threading (I can't remember the exact threading off the top of my head), thread it into the hanger, and use as a lever to bend it back. This works amazingly well, from my experience, but there is the possibility of stripping the threads.

Joshua A.C. New 10-06-07 12:11 PM

... or, alternately, put it in a vice and go at it with a pain of channel lock pliers, perhaps with some wood in the jaws to keep from biting into the hanger. Bend it, look, bend it, look...

It'll never be perfectly aligned and sooner or later it will be too soft to keep using, but until that happens, you can extend the life of the thing dramatically.


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