Pazu Posted August 14, 2012 Report Share Posted August 14, 2012 Finally able to afford a decent trials bike, I've got my Neon Wing. Never had disc brakes before, haven't been able to afford them before. The Wing is dual disc. I had the bike on the work stand, working on chain tension, somehow unbelievably I allowed my right hand to drift too close to the rear wheel, touched a pedal with my left hand, wheel rolled a little and >SNIP< the rear brake disc bit the tip of my middle finger. Damn it I am always using that finger to express myself and need it to be as long as possible, for visual acuity. The rear wheel was barely moving yet there was still enough force to pin my finger between the fin of the brake disc and seat stay (if that's what it is called on a Mod). The inside edges of the stamped out disc are so sharp, it instantly cut my finger about 1/3 through so, I've still got all my fingers & toes but WATCH IT if you are new to disc brakes, these things could take off a finger in an instant. Now I can barely type and have to lay off trials for a few days until my finger tip sticks back together. No guitar either, STOOPID! I will not be making this mistake twice and hope that by mentioning it, I can help some other NOOB avoid this unpleasant surprise. Please be more careful than I was! I'm thinking of covering the spaces between the fins with packing tape or something. Probably there is a reason why that isn't done. A decal that was cut to fit the dimension of the slots, would do it. I can't believe that there is much heat build up on those discs while riding trials, but I don't really know. 1 Link to comment Share on other sites More sharing options...
Martin Reynolds Posted August 14, 2012 Report Share Posted August 14, 2012 BEST post ever! Its called natural selection 3 Link to comment Share on other sites More sharing options...
the mysterious leemur Posted August 14, 2012 Report Share Posted August 14, 2012 I know the feeling , a while ago I was showing a mate how my disk rotor had gotten lose by trying to wiggle it but I forgot I had the bike off the ground and got my finger pushed against the caliper and since it hit at an angle I have a unnaturally slightly flat little finger... :$ 1 Link to comment Share on other sites More sharing options...
Azarathal Posted August 14, 2012 Report Share Posted August 14, 2012 Tore through half my thumb nail once, not nice. Link to comment Share on other sites More sharing options...
weebryan Posted August 14, 2012 Report Share Posted August 14, 2012 I had a hope xc brake many moons ago and was rubbing a little so was trying on shims and spining the wheel to see if was ok was still rubbing, so i slackend off caliper and spun wheel to see what was need and i put the washer in and tighten up and brill no rubbing so i gave the caliper a final wiggle to see if was tight enough and my finger touched the rotor and jammed in the caliper , put my finger in my mouth and tried wheel again and was jammed solid, took my finger out my bloody mouth and argh no finger tip totally straight. So going to work was fun as being an engineer, every one was saying stop moaning and get on with it, took plaster off and showed them lol not fun try to screw thing together with a tip missing 1 Link to comment Share on other sites More sharing options...
knave Posted August 14, 2012 Report Share Posted August 14, 2012 My best friend literally can't talk about this this issue. He *almost* did the tip of his finger once and literally can't talk about the subject of fingers/disc rotors. It's hilarious. When I was giving the rotors a quick clean with some kitchen roll and a bit of brake cleaner by just spinning them through a fold of kitchen roll, he literally had to walk away, he couldn't watch. lol 1 Link to comment Share on other sites More sharing options...
Revolver Posted August 14, 2012 Report Share Posted August 14, 2012 He literally can't talk about it? What happens if he tries...? I hope it's not messy. Link to comment Share on other sites More sharing options...
dezmtber Posted August 14, 2012 Report Share Posted August 14, 2012 ia few months ago i was in the shop and a lady with her son bought a jump bike in to have the brakes looked at and while i was checking it in the stand i span the wheel to see wahts up and the lady pointed out the problem a little to well and took the tip and the tip of the bone of her index finger on her right hand. it was bloody shocking the wheel didnt even slow down one bit. be warned disc brakes are easily as dangerous as cicular saws. 1 Link to comment Share on other sites More sharing options...
Pazu Posted August 14, 2012 Author Report Share Posted August 14, 2012 (edited) I'm becoming more and more afraid to check this post - as the tales from the field, become darker and darker. I'm beginning to suspect, why disc brakes work so well... they're the DEBBIL So it can be factually stated, that disc brakes are more dangerous than hydraulic or other systems, due to the "chop factor." Yikes! Edited August 15, 2012 by Pazu Link to comment Share on other sites More sharing options...
onza pro series guy Posted August 14, 2012 Report Share Posted August 14, 2012 Only time this happened to me there was a knock at the door as soon as I had done it. By the time i had finished swearing and sucking my finger (giggidy) I had to try and open the door, which hurt like hell and got blood everywhere. At which point a delivery guy practically threw a stupidly heavy parcel into my hand as soon as I had opened the door. Not good. 1 Link to comment Share on other sites More sharing options...
Pazu Posted August 15, 2012 Author Report Share Posted August 15, 2012 (edited) I wonder if this has been invented or suggested yet, I could not find it in a search. If done before, it bears repeating. Would be good for kids bikes. Here's a vid of my push test. Wouldn't be hard to tape a brake disc that was off of the hub, with a template of the circumferences involved. Clean it. Tape with overlaps across wax paper with packing tape, use the template to cut away the excess with Xacto knife. Peel away the wax paper then stick it on the outside facing of the disc. That's what I did, yes it's very crude because MY F'N FINGER IS IN A BANDAGE I decided that I would work on my bike with my riding gloves on now... No, they are not fingerless. Edited August 15, 2012 by Pazu Link to comment Share on other sites More sharing options...
Topsy Posted August 15, 2012 Report Share Posted August 15, 2012 (edited) For me chains are much worse My mate had just tensioned a fixie's chain, then whilst cleaning the chain and talking to a customer his thumb slipped into the front sprocket and got stuck half way through. He had to pedal back to get it an could clean up the blood all over his shop.. He's now got a numb tip on his thumb as the sprocket went through a rag and his nail neatly to the bone, and he refused to see a doctor (idiot^^) Definitely don't need to see that again. Edited August 15, 2012 by Hopping_Topsy 1 Link to comment Share on other sites More sharing options...
Revolver Posted August 15, 2012 Report Share Posted August 15, 2012 This isn't that big an issue. What you do, and you'll kick yourself when you see how simple it is, is not put your fingers in a spinning disc brake. Easy as that. I might add that spokes are just as deadly, should we get rid of them? 3 Link to comment Share on other sites More sharing options...
Martin Reynolds Posted August 15, 2012 Report Share Posted August 15, 2012 What you do, and you'll kick yourself when you see how simple it is, is not put your fingers in a spinning disc brake. This! I refer to my earlier comment of natural selection. If you put your finger in a sharp spinning metal disc, you get what's coming to you. Its not bad design, it's you being a f**king moron! Link to comment Share on other sites More sharing options...
knave Posted August 15, 2012 Report Share Posted August 15, 2012 He literally can't talk about it? What happens if he tries...? I hope it's not messy. Some are guilty of overusing and/or misusing the word "literally" but I'm not - he will not speak about the time that he caught his finger in the rotor nor will he speak about the possibility of anyone else doing so. He actually clamps has hand over his mouth and shakes his head, it turns his stomach immediately. The thought of it is like nails on a blackboard to him, makes his skin crawl. It really is hilarious. Link to comment Share on other sites More sharing options...
Pazu Posted August 15, 2012 Author Report Share Posted August 15, 2012 (edited) LoL Revolver and Martin thank you for pointing out the obvious though it is not myself that is my concern; I've already learned the lesson here. It is others. Such as my two sons. Such as the woman missing finger and bone, from the earlier example in this thread. The kids at the skate park. Jamming a finger in a hand spun spoked wheel would have no effect, it is not the same thing. A disc brake is the same design as a meat grinder blade and works as effectively. Why do I have an exposed meat grinder blade on my bicycle... Overstating the obvious, don't put your finger there, yep that works, and it's always fun to call someone a f**cking moron, but keep in mind that there's lots of curious fingers out there. The only fingers under your control, are your own. Taping off a disc, lessens risk for others. Not saying that it's any big deal. Just that a potential solution is out there. Edited August 15, 2012 by Pazu Link to comment Share on other sites More sharing options...
Dan_Trials Posted August 15, 2012 Report Share Posted August 15, 2012 Making things so that you can fumble along and stick your fingers any where and not get them chopped off is not really a good thing. It makes people less aware of what they are doing, so they don't have to see things or pay attention to what is going on. Link to comment Share on other sites More sharing options...
Pazu Posted August 15, 2012 Author Report Share Posted August 15, 2012 Making things so that you can fumble along and stick your fingers any where and not get them chopped off is not really a good thing. It makes people less aware of what they are doing, so they don't have to see things or pay attention to what is going on. You seem to be suggesting that mechanical safety measures lead to carelessness. I would have to agree to disagree on that one, I do not think that there is a measurable correlation. Do you have an example of this to cite? There are on the other hand myriad examples of safety measures that have led to reduction in accidental injury, in about every field of human endeavor. We are all differently abled in terms of ability to interpret new situations and anticipate danger. Children don't have the experience discipline or mental development of an adult and so by definition are much more vulnerable to dangers such as this. Adults are prone to distractive secondary behavior such as drinking, sparking one etc. I am not judging this behavior, merely pointing out that altered states are common. This also makes people less aware of what they are doing. A protective mylar sticker over the chopping area of a brake rotor cannot in and of itself promote distractive behavior. I know that I am a very risk-averse person and understand that this is not an issue for an experienced mechanic or rider. It is getting through the NEWB stage with fingers intact that motivated me to think further about it. Again, we are talking about fingers of people here. Anyhow, I've called SRAM/Avid regarding the idea. They could easily have a product such as this on the market in no time. They would just call their sticker supplier with some dimensions & it would be done. So I'm pissed off at having cut myself on the rotor, fair enough but it's not about me it's about future riders and wanting to promote safety in an thrilling sport that I enjoy. Something so simple, lightweight and not performance-affecting, could have prevented this bloody injury of mine. I felt it worth mentioning, is all. Link to comment Share on other sites More sharing options...
Luke Rainbird Posted August 15, 2012 Report Share Posted August 15, 2012 You're riding a bike with no seat and an exposed drivertrain up and off walls and rails, so bigging up the whole "It's a massive safety issue" thing is pretty moot. I've got friends who've caught fingers in discs before though - it's a bitch for sure. 2 Link to comment Share on other sites More sharing options...
Funface Posted August 15, 2012 Report Share Posted August 15, 2012 Not good but I knew someone who had 20" mod front freewheel and the chain came off while he was riding so he desided to try and put it back on still moving.. his glove got caught and his finger went in between the freewheel and chain he lost 1/4 of his finger.. Link to comment Share on other sites More sharing options...
Pazu Posted August 15, 2012 Author Report Share Posted August 15, 2012 You're riding a bike with no seat and an exposed drivertrain up and off walls and rails, so bigging up the whole "It's a massive safety issue" thing is pretty moot. I've got friends who've caught fingers in discs before though - it's a bitch for sure. Well I didn't call it "massive," just one way of avoiding one specific issue that doesn't come up much. I suppose that I have gone on, a bit... It is not critical. Surely I'm not the only one thinking about new products for the sport? Perhaps I'm the only one thinking about dumb, unnecessary products... I just think that somebody's momma would buy one of these for her kids' bike in a heartbeat, at the mere mention of it. And that's more work for the lbs, maybe advertising if there's print on it, could bring in other sales, I don't know. What can I say, I am a Noob, that's my excuse! Link to comment Share on other sites More sharing options...
Topsy Posted August 15, 2012 Report Share Posted August 15, 2012 Well if you're aiming at kids, you could just as well develop some plastic guards that "snap" into the rotor. You could have it in all colours 1 Link to comment Share on other sites More sharing options...
bikeperson45 Posted August 15, 2012 Report Share Posted August 15, 2012 I was expecting a gory picture, but looks like I'll have to fulfil my sadist needs elsewhere on the internet. 2 Link to comment Share on other sites More sharing options...
Pazu Posted August 15, 2012 Author Report Share Posted August 15, 2012 (edited) Well if you're aiming at kids, you could just as well develop some plastic guards that "snap" into the rotor. You could have it in all colours Yeah that could work, rotors come in lots of different styles, would have to cast ones for every style I suppose... So I heard back from SRAM/Avid, talked to a product development guy there, he says he will bring the idea to the table and see what other people think. His first thought was that rotors get to 400 F, good point but I pointed out that I was targeting trials riding & kids. I mentioned that high heat mylars and adhesives are out there. So I didn't get the "we can work with you on this" response that I had hoped for, but hey the guy was very decent and thoughtful on the phone so who knows. He gave me his email address to send my pic & link. I've checked & it appears that mylar film can handle 200 C, 392 F so it might work even then. I know from other experimentation that plastic films are okay conductors of heat and so the majority of the film would stay comparatively cool, and might even contribute to dissipating heat off of the rotor which if true would add to the positive rationale for the potential product. Edited August 15, 2012 by Pazu 1 Link to comment Share on other sites More sharing options...
clerictgm Posted August 15, 2012 Report Share Posted August 15, 2012 (edited) Thank god I ride brakeless! Edited August 15, 2012 by clerictgm 1 Link to comment Share on other sites More sharing options...
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