Bicycle Mechanics - Your most grueling/labor-intensive fix?

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.




rolliepollie
04-26-11, 09:20 AM
I just spent about 2hrs filing the stop of my steering tube in the middle of the night, trying to do it as quietly as possible which means short, forceful strokes. That and trying not to breathe in the smell and metal shavings. But once my stem and headset fit snugly it feels like I just built a wheelset.


Greenfieldja
04-26-11, 10:28 AM
Most labor intensive was getting sh**y V-brakes to work properly on a POS bike.

I was offering a repair service to the US Embassy community here in Morocco (still do on a case by case basis). One of the staff had bought a new bike and thought it was a good deal. Between the v-brake calipers, the crappy plastic body the levers attached to, and the long housing run without any cable stops...getting the brakes to function at all was nothing shy of a miracle.

-j

San Rensho
04-26-11, 10:34 AM
Cottered crank removal without the special tool. Hammering, soaking in PB Blaster, pleading, blashemy, c-clamps, all to no avail.

Then I borrowed the tool and it was like the heavens parted. Both cranks off in less than 5 minutes. With the right tool, cottered cranks come off easier than square taper cranks.


phoebeisis
04-26-11, 10:46 AM
SEAT POST REMOVAL!!
Just paid $20 for a Trek 930- parts in rough shape- ok frame.
As usual the seat post is stuck- HARD!
Put pipe wrench on it- lubricant- nothing.
I'll try ammonia(how long are you supposed to let it sit- overnight??
Don't expect that to work.
I'll finally end up cutting it-then slipping a hacksaw blade down the hollow post- making two-CAREFUL- full length cuts thru at 6 and 12 oclock-(takes maybe 2 hours- no kidding 2 hours- Least fun job-especially since it didn't have to happen- BUT ALWAYS DOES!!
A decent Trek 930 sells for $150-$200 here in NOLA- not the $80 most of you guys get for DB True Temper MTBs. I wouldn't bother doing it for $60.
Charlie

FastJake
04-26-11, 11:20 AM
The one that comes to mind is a recent seatpost removal from a 1986 Schwinn Voyager. Everything on the bike was rusted. Ended up putting the post in a vise and cranking on the whole frame. It was difficult the whole way but I did get it out.

daveizdum
04-26-11, 11:25 AM
Removing a stuck bottom bracket that hadn't been greased or cleaned in 10 years. At least four mechanics contributed to the effort. Someone broke a wrench and a vice. Someone else tried a blow torch. A lot of PB Blaster was used. Eventually I (the only one who wasn't a mechanic) got it unstuck using better wrenches, some bolts, and a stronger vice.

BCRider
04-26-11, 12:10 PM
Drive side crank arm with stripped out extractor threads and that had corroded tight to the BB axle. Cut most of the way through the aluminium with one of those small "tight quarters" hacksaws and then split the hub apart with a cold chisel ground to a longer taper to generate enough pressure. A hell of an arm melting job and it wasn't even one of my own bikes.

frantik
04-26-11, 12:55 PM
I spent over an hour the other night pulling out a stem which i swear is like one MM too big for the steerer tube. it wasn't held in by rust or anything, just a lot of friction. just getting the nut to drop down was a chore and took a hammer, but that had no effect on how easy or hard it was to pull up the stem and bars

i had no vise or bike stand, so i had to try to stand on the wheel to hold the bike down while turning and pulling up on the stem. eventually i figured out the best way to remove it was to move the stem back and forth which would cause the head tube and stem to warm up from friction.. then i'd cool the stem by holding it, then i'd move and pull up on the stem. I'm still sore and have bruises on my legs lol

dwellman
04-26-11, 01:08 PM
My mother-in-law's bike left outside for a while. . . getting the pedals off. First one soaked in PB and it gave after 36 hours or so. Second. . well . . I let it sit for 12 hours, PB another 12 hours PB another 12 hours PB another. . finally I wrapped some dirty socks around a wrench, pre-tensioned it in the pedal and beat the hell out of the wrench till it gave.

Almost the same deal with a seized stem bolt. . . gives new meaning to "break it loose". Just had to pound on the end till it popped.

dwellman
04-26-11, 01:13 PM
Oh this bike also has internal cable routing. I'm. . I'm just gonna leave them be.

jeepr
04-26-11, 04:24 PM
I think it's a tie between a stuck seat post in a Specialized Hardrock, and a corroded in stem in my Kuwahara. I had less luck with the stem. I ended up cutting the neck off so I could get the fork out of the bike, then the fun started.. :D

Sledbikes
04-26-11, 04:54 PM
neighbors bottom bracket overhaul on his really dirty old D/S schwinn mtb. first the stupid crainring crank corroded itself to the shaft breaking the threads on the crank then 45 minutes hitting it with a torch, a swift blow from a 4lb improvised crank removing device i was able to spend the rest of the day removing the caked on grime to get at the bottom bracket notches it was easy there once i switched from breaker bar to impact gun. the shaft was chewed up since it was ridden basically with no bearings i jb welded the ruts smoothed it, greased it, and put everything back together and gave it back to the owner.


i made 20$ on that job :notamused:

fishymamba
04-26-11, 05:21 PM
Cutting my cheap walmart bike in two pieces so it would fit in our trash can. Only thing I used was a tiny rotary tool I bought from a wholesale store. Took me three hours.

Bianchigirll
04-26-11, 05:33 PM
my most grueling job was either, having to repair a dropout on a real crappy bike after the wheel came loose and I was accused of doing a shoddy job on and made to fixt it.

or when I was using the Cannondale repair kit to put a replacement hanger on an old MTB with 24" rear wheel. drilling the holes went fine but the tap busted in one of the holes. OY!

HillRider
04-26-11, 05:52 PM
Trying to make a Neighbor's sub-department store quality bike work properly. Absolutely nothing I could do would make it shift properly, including replacing the front derailleur with a decent parts-box Sun Tour. The brakes were as bad or worse and I won't even get into the hub and bb bearings. I spent an entire afternoon and evening on this POS and it still wasn't even close to right. Ugh!

Perhaps that explains my uncharitable answers to threads that start; "I just bought this bike at Walmart and....".

reptilezs
04-26-11, 06:10 PM
Trying to make a Neighbor's sub-department store quality bike work properly. Absolutely nothing I could do would make it shift properly, including replacing the front derailleur with a decent parts-box Sun Tour. The brakes were as bad or worse and I won't even get into the hub and bb bearings. I spent an entire afternoon and evening on this POS and it still wasn't even close to right. Ugh!

Perhaps that explains my uncharitable answers to threads that start; "I just bought this bike at Walmart and....".

sometimes i wonder why i bother adjusting hubs on kids bikes and such. axles with terrible run out and what not make adjusting it somewhat useless. then again sometimes the cones are so tight that the wheel will jump out of the truing stand and sucker punch you in the face if you are not paying attention.

Mr. Beanz
04-26-11, 06:14 PM
Trying to remove a pedal from the tandem. Soaked in lube overnight but no dice. During one attempt the pedal wrench slipped and I ended up punching the chainrings!:eek:

Ended up driving my bloody knuckles over to a buddy who pulled the cranks and then placed in a vice to get the pedal off.

dwellman
04-26-11, 09:24 PM
But I'd rather work on bikes than firewalls. . especially OTHER people's firewalls...

FBinNY
04-26-11, 09:44 PM
Some years back a dealer called me and asked if I could get a bottom bracket tap out of a brand new Colnago frame. His mechanic was prepping the sold frame for a build out. It got a bit tight, and he tried to bull it through, until he sheered the pins off the Campy tap handles. Par for the course, they tried working at it themselves before calling and they were seriously stuck.

4 hours of serious elbow grease later I got them out, but next time, the frame and tap go to the bin before I go through that again. BTW- it was a favor for a good customer so no money changed hands, just a few beers.

Bikedued
04-26-11, 10:19 PM
Try swapping everything over to a smaller sized frame when a customer orders the wrong size, on a 2011 Giant Trinity SL1!!?? Most monumental pain in the rear job I've ever been handed.:lol:.,,,,BD

Internal routed EVERYTHING... Completely unreal....! I'd rather rebuild 10 cottered crank bottom brackes on bike boom era road bikes.

http://www.chainreaction.co.nz/images/products/0.3547.png

Jeff Wills
04-26-11, 11:07 PM
Not a bike I worked on, but it was a long-term project in the shop where I worked: customer brings in a frame and a box of parts he wants put back together. He had disassembled it and then sent it to a plating shop- completely chrome-plated. Very nice, very, pretty... oops, he hadn't removed the right-side bottom bracket cup. Ever try to remove a chromed-over BB cup? I don't think it can be done. The ace mechanic tried a couple different tools (including a Stein double-clamp type wrench) before crying "uncle" and sawing it in half with a carbide saw from the inside. Then we had to clean up the BB threads. Remember that the whole frame was chromed? Yep, plating in the BB threads.

Just to make it a little more interesting, it turns out the bike has Swiss threads. How do you find a set of Swiss BB taps (bearing in mind this was about 1980)? How do you convince the (very frugal) shop owner to pony up for some expensive tools that would likely be used once and never used again? Finally, after weeks of searching, the frame went out to a framebuilder who had the correct taps.

So, the fixed cup is toast. Where do you find a Swiss-thread replacement? I don't know either- we ended up buying a Phil Wood BB and selling it to the customer at cost. The rest of the bike went together pretty nicely. It was Campy Nuovo Record mostly (the frame seemed to be a high-end racing bike- hard to tell with all the chrome), but here's the kicker: because the customer wanted to ride in his flip-flops, we installed Schwinn rubber-block pedals. I think we finished the bike 3 or 4 months after it first came through the door.

Chrome frame, full Campy NR, rubber pedals, flip-flops. Makes quite an image, doesn't it? It's stuck with me for 30 years.

FLYcrash
04-27-11, 01:11 AM
Getting a dead cottered BB out of an old Raleigh and replacing it with a modern BB, a process that partially damaged the BB threads:

http://www.bikeforums.net/showthread.php/701976-Bottom-bracket-mess

kmv2
04-27-11, 09:50 AM
I think bikes are the reason I stopped owning and working on cars as much as I used to. Cars are much more of a pain in the ass.

Bikewise though, probably getting aluminum seatposts/stems out of steel frames. Also some old 10-speed bottom bracket cups that never want to come out.

Sixty Fiver
04-27-11, 10:04 AM
Frozen seat posts and stems... few things are more challenging than this.

DCB0
04-27-11, 10:30 AM
I used to volunteer at a bike co-op and the standard practice was, before doing anything else to a bike, check that the seatpost, stem and bottom bracket cups were not stuck, and if they were, strip all usable parts and trash the frame. The only exceptions being nice quality frames with these problems when enough volunteers were available... the hours spent removing a bottom bracket from Bianchi Grizzly or Rocky Mountain Fusion didn't feel as wasted as the same hours spent removing a seatpost from a Free Spirit or Supercycle.

Generally the bikes that were worth the effort were monumental PITAs - usually involving stripping all parts except the seized ones and improvising tools and cheater bar arrangements to maximise the chances of removal.

kralizec
04-27-11, 10:45 AM
installing bottom bracket cups on the wrong side, both sides reverse threaded. At least I don't have to worry about them creeping out...

I facepalmed when I looked at another bike with similar bb.

phoebeisis
04-27-11, 10:47 AM
Took 3 hours of sawing and then 5 minutes of twisting to get this seatpost out - 10" of it was inside the frame-
The seat post has .110" thick walls- typical cheap aluminum seat post- real pain to cut through.
Only about 3.5" were really welded/rusted together, but that was enough. Initially I couldn't even pound it in with a 3 lbs maul(ammonia soak-penetrating oil.

I made two full length cuts with the hacksaw blade-at the deepest end the cuts were over1/2 thru.This allowed the post to be sorta' crushed to a slightly smaller diameter(especially in the first 3.5" where the corrosion/joining had taken place).

It is a miserable job!! I've used this method 4 times before-always successful, but very labor intensive. I used a power tool- grinder with cut off blade- to cut the top off the seat post. The rest was strictly human powered. Even if I had a power tool that would power the naked blade, it would be tricky.

I hate stuck seat posts?

Oh- it doesn't look like either the ammonia or penetrating oil actually penetrated the top 3.5" of welded corrosion.
Charlie
PS I'm still open to suggestions on an easier way to do this.
PPS- A Trek 930- 21"- with ok components is worth about $175 here in NOLA- costs $20 will add cables, pedals, rear wheel, seat post seat- stuff I already have which is worth close to zero(maybe $25) by itself.DB True Temper OX frame- younger folks like quality steel framed bikes ( 5 universities) for under $200.I'm off this week- no $$ coming in- so might as well.

jeepr
04-27-11, 10:54 AM
PS I'm still open to suggestions on an easier way to do this.


I remove the bottom bracket, flip the bike over, and pour ammonia down the frame. It works best if the ammonia stays in there, so if the seat post is the kind with a hole all the way through the top, plug it so the liquid stays inside. I use a lot of ammonia so I know the seat post is filled all the way past where it is stuck. I put a bucket under the bike so as it runs out, I can re-use it. Eventually the post will turn side to side and the liquid gets down in there.

phoebeisis
04-27-11, 12:36 PM
I've heard of the ammonia trick, but I cheaped out and just tried some low concentration ammonia in glass cleaner which we had already.
Next time I'll buy full strength ammonia- pull the BB and give it a try. Sawing/Slicing the post is such a long labor intensive job that it makes sense spending 30 minutes or so removing/replacing a BB.
Do you leave it all night - or several days-or just a couple of hours?
Thanks
Charlie

Sledbikes
04-27-11, 02:25 PM
drill across post with either 1/4 or 3/8ths insert 2ft long steel rod of either and twist. use 3/4 if you plan on using hammers