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NFLcheesehead1

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Discussion starter · #1 ·
I was riding my bike (2012 Trek 4300 Disc) back from class today, and as I picked up my bike to take up to my room, the back tire completely fell off the bike onto the ground. It caught me completely off guard. It was a typical ride to and from class...but for some reason the tire just fell out when I picked up the bike.

So I tried to put the wheel back in, but couldn't get the Disc back in between the brake pads. I tried to loosen the brake pads, but wasn't sure which bolt to unscrew. The bolt I tried was incredibly tight and when I tried to loosen it, I heard something snap...not sure exactly what snapped, but I was then able to get the Disc in between the brake pads. After the snap though, I pretty much lost all my break fluid. I put the tire in place and it seems o.k. but I noticed the the tire doesn't spin as freely as it did before. Also the rear brakes don't work anymore.

I think I'm gonna take it to a shop to get an expert to look at it 'cause I just started mtbking this Summer, and I know squatdidely about repairing bikes. Any suggestions on what I should do or look at? (I really wanted to go riding this weekend :madman:) Thanks a bunch!
 
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#2 ·
Start by learning to adjust a quick release.
Park Tool Co. » ParkTool Blog » Wheel Removal and Installation

Hydraulic disc brakes self-adjust to correct for pad wear. There actually aren't any external adjustments, or at least not on mine, on a hydraulic disc brake caliper. If the brakes are applied without a disc rotor between the pads, they self-adjust to the new position, which is obviously way too far in. Some brake models are even damaged by this.

Since the fluid's leaked, your pads are probably toast. There are plenty of threads debating this back and forth, so do a search on the topic. People do have ways they propose for cleaning them. For me, it's a relatively inexpensive part and trying to fix them is a relative pain in the ass. So I don't do it.

If you got fluid on the rotor, you need to clean that too. Wipe most of it off with alcohol. If your rotor still looks like it has an oil slick on it, heat it up until it stops smoking. I just used my stove. It's electric, so not very fast. Heating quickly and unevenly wouldn't be very good. Your shop can probably also take care of the rotor for you, since you're going there anyway.

The rear brake needs to be bled. It's possible that you damaged some seals. It's possible that you damaged something important attacking whatever mystery bolt you accosted.

I don't imagine it'll take your shop that long to get your bike rolling. Call ahead and find out how busy they are. Help them help you, basically.

In future, look things up on parktool.com before you try something you haven't done before. If after looking at the Park Tool site you're still not sure, the shop's not a bad idea. None of this stuff is rocket science, but a lot of it isn't that intuitive anymore either.
 
#3 ·
One bolt(banjo) fastens the brake hose to the caliper and that hollow bolt allows the hydro fluid to transfer to the caliper and push the piston out. It can be snapped because it is hollow if you overtighten it. You may have to replace the caliper if a broken piece is stuck in the bolt hole.
There is no need to adjust the pads to get the rotor positioned unless you squeezed the lever when the wheel was out. Doing that would bring the pads together. You would need to pry them apart with a table knife, paint scraper or other suitable tool and squeeze the fluid back in.
This stuff is easily learnable but not usually without a video or some instruction.
 
#4 ·
That's pretty wierd that your QR skewer was so loose that the wheel fell off. Someone must have "helped" it.

There should be no need to do anything to a disc brake to take off/replace a wheel. Its one of the nice things about disc. What Andrew said is no doubt it, you sqeezed the brake lever when the wheel (and thus the rotor) was off, and the pads adjusted too far. You need help. Besides the bike shop, does your school have an outing / outdoor club? Might be someone there that would help you fast (and free).

Whatever else happens, check those quick releases before you ride!
 
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Discussion starter · #5 ·
^Yeah, I was thinking the same thing in regards to some sort of "sabotage." I can recall applying the brakes though without the Disc in place, which would explain my difficulty in getting it back in place. I wish my university had a mountain biking club, but as far as I know, we don't. I'm pretty sure I just need to readjust the brake pads and add brake fluid...but I'm still gonna take it in to get it examined 'cause I would hate to have any mishaps while flying down a trail. Thanks for everyone's help...if anything, this is at least a learning experience.
 
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Discussion starter · #6 ·
UPDATE: I took the bike in and the brake caliper is toast...so, it's about $100 to replace it. Oh well, I'm just hoping this won't happen again. Looks like I got about a week to get the new one!
 
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#7 ·
If you at all know which way to turn things, you probably loosened a bridge bolt which is generally very tight. If you do that, the 2 caliper halves aren't held apart as tightly and you might leak fluid.

It's hard to imagine loosening a bolt messing up your caliper, I think the bike shop is screwing you.
 
Discussion starter · #9 ·
I seriously hope the shop isn't pulling a fast one on me just cause I'm new to this and young...The guy seems trustworthy though. He also told me that I have to buy one with another brake disc as well because that's the only way they come. That sounded a little fishy to me...
 
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#10 ·
I second the gesture that the bike shop may be pulling a fast one on you. Depending on the damage of the caliper... which doesn't sound like you did much to it... you shouldn't have to replace it. Then again, stranger things have happened. I personally don't think that calipers and discs come together, but maybe someone with more experience with this can second or disregard that. Don't give them any money just yet, this seems fishy.
 
#11 ·
NFLcheesehead1 said:
I seriously hope the shop isn't pulling a fast one on me just cause I'm new to this and young...The guy seems trustworthy though. He also told me that I have to buy one with another brake disc as well because that's the only way they come. That sounded a little fishy to me...
Click to expand...
The packaging varies by brake. Part of how I ended up with Avids is that they're sold as sets. I needed to buy a complete front brake and a complete rear brake. Shimanos were the other brakes I was considering at the time, and they were going to come in a package with a lever and hose, a package with a caliper, and a package with a rotor. So, two packages vs. six - it was going to be a lot cheaper to do Avids, and I was able to throw 'em on my bike and go.

Most mid-level and high-end systems on bikes can be bought piecemeal, especially by shops. It doesn't cost you anything to phone another shop and ask. You might also need a Hayes dealer to get parts, while their retail-packaged products are probably available to a whole lot more shops.
 
#13 ·
?

Bikes require regular maintenance...or they fall apart;) check your bike before every ride.Some ******* dialed out my front BB7 brakepads as my bike was locked up in the company bike cage, came to a four way stop on my commute home and had a scare, that is a lesson learned.
 
Discussion starter · #14 ·
Thanks for that link Cobba. I called the shop and told 'em about just getting the Hayes Dyno Assy Kit for $40 instead of a whole new brake and disc for $100. He explained that if I did this, they would have to bleed the brakes, which they charge about $40-50 to do that...so, I think I'll just get the new one and have an extra disc for the future. If I knew how to bleed brakes and stuff I would definitely go for the kit instead.
 
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#15 ·
Too bad you don't live closer or I'd say "Bring it over, and I'll be glad to teach you how to fix it". Not real sure why you need a new caliper? If the banjo bolt is broken inside the caliper you can take it to a machine shop and they can take the broken bolt out. (In my opinion the bike shop should have done that for you, but I'm not there to see it all and understand it all). If you can send some pics of the broken "bolt' and how deeply it is brokne inside the caliper it might help. Best wishes!
 
Discussion starter · #16 ·
I would get some pics, but I left the bike at the shop this whole week...it should be done either Saturday or Sunday. It stinks 'cause my college has this Thursday and Friday off and I wanted to go biking. I really need to start learning how to fix and maintain my bike properly to avoid so many trips to the shop. The shop I took it to is Bikes Unlimited in Downtown Lynchburg, VA. Not sure if any of you know if it's a good shop or not, but I've heard from a couple friends that they're pretty good.
 
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#17 ·
NFLcheesehead1 said:
Thanks for that link Cobba. I called the shop and told 'em about just getting the Hayes Dyno Assy Kit for $40 instead of a whole new brake and disc for $100. He explained that if I did this, they would have to bleed the brakes, which they charge about $40-50 to do that...so, I think I'll just get the new one and have an extra disc for the future. If I knew how to bleed brakes and stuff I would definitely go for the kit instead.
Click to expand...
Should be a minimum labor charge kind of a deal - $15 or so, unless there's some parts replacement involved that's getting missed in translation.
 
#18 ·
I would see if there is a bike collective or maybe a bike club in your area. Or at least try a quote from a different shop. It sure sounds like the shop is trying to sneak some extra money out of you by inflating the problem.
 
#19 ·
I would concur that 100 sounds awful steep for an entry level hydro, even with labor/installation.

I've seen shops that charge 25 labor per hour/per part installed, but I have a hard time believing that a shop in a city would charge that much...but seeing as how I've never been there, I'll reserve my judgment. For what it's worth, the place I work doesn't charge labor hourly, just per service.

Buying a kit means they will have to cut and bleed the hose, anyhow, so I fail to see what the issue they are having with this is. If you get a bike back with a pretty loop of hydro cable somewhere, be sure to gently suggest that shortening the cable is part of the job.
 
#20 ·
I'm used to shops charging about $60/hr. But most things tend be charged either with preset pricing or it only takes 15-30 minutes for the mechanic to get 'er done, and there's usually also a minimum labor charge. So IME it takes either a pretty extensive repair or something that's gone a bit sideways for the hourly rate to really kick in.

It's interesting how differently different shops charge. I know there are a few different business models, and after that there's issues of rent and the general wage of an area.
 
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