| Author | Message | ||
     Ferrisbuellersdayoff |
If the ZTL system is so great why have bicycle manufacturers started equipping mountain bikes with disc brakes rather than leave the rim clamping style? theoretically the rim clamp works similarly to the ZTL perimeter brake. Besides I was told never touch one of the disc brakes on these mountain bikes because the oils from your hands cause the brakes to not grip. And the dirt of your finger prints ruins the calipers. Hmm mountain bikes go through some nasty trails, right? so whats the point of this extremely fragile braking system. I swear everyones becoming weak in this world. | ||
| Tramp |
Rim clamps collect mud and dirt (it gets thrown to the outside), discs stay a bit cleaner and also self-clean better. It's not so much a bicycle v mc thing, as it is a dirt v asphalt | ||
| Birdy |
You can also overheat a rim and blow a tire on a Bike, Use to be a problem with a type of tire, called a tuber or sew up, that glue to the rim. | ||
| Slaughter |
Road racing makes better use of the rim-jobs (sorry about that) I have a Hayes-hydraulic brake mountain bike that is great for taking a ski-lift up for a long downhill run. | ||
| Benm2 |
The movement of bicycles towards disc brakes has made wheels heavier. The benefits of disc brakes on MTN bikes are to keep the braking surface cleaner & less sensitive to water. I've worn through / cracked mountain bike rims before I changed to a front disc. The front disc is MUCH better on muddy trails, but my front wheel got at least 100g heavier. Plus when you DO bash rock/tree/pipe/railroad tie and mangle the rim, you're brakes dont go away too. The MTB disc was a BIG improvement. Do not take any real estate tips or stock advice from the person that told you dirt from your fingerprints ruins your calipers. | ||
| Tramp |
the same hyper-anal dynamic presents with techno-dweeb snowboarders and skiers: the old "don't touch your freshly-waxed base, the oil from your fingers will slow you down" line of bushlit | ||
| Nillaice |
i got a mtn bike and bent the rims to sh!t. i don't ride it much anymore cuz now the brakes pulsate or just plain ol' lock-up. wish i gad got one o' them facny-shmancy rigs and i think they look pretty neat too | ||
| Danger_dave |
Which moron is breaking motorcycles? | ||
| Danger_dave |
>>i got a mtn bike and bent the rims to sh!t.<< I kept busting spokes so I had it respoked with the good gear - just get some better rims. Option & exclamation mark gives ¡ btw. :-) (Message edited by danger_dave on May 20, 2008) | ||
| Neurorider |
Yes, what Nillaice said, I think. With rim brakes on a mtb if the wheel gets tweaked on a ride (which is almost every ride for me) the brakes rub and you have to stop and true the rim or loosen the brakes. If you're on some of the trails I ride, you can't ride out with a loose brake. With disc brakes you can't even tell if the rim is a bit out of whack as it doesn't affect braking. The discs are a little less vulnerable since they're smaller. They also don't melt things when they get hot, like rim brakes can. I think they're easier to modulate, too, as the rim brakes I used to have would be more on/off after they were hot. doc | ||
| Mtch |
i've worn through rims in 6 months, changed to disc, and tho heavier its better in the mud (i ride more in the winter), also much downhill is not scarey any more. ps. dont touch a disc brake after using it hard either mtb or moto! how do i know? shouldn't need to ask LOL (Message edited by Mtch on May 21, 2008) | ||
| Microchop |
OK, we are talking about 2 very different situations here. Rim brakes are nearly always rubber pads on aluminum rims. Sometimes the rims are anodized, sometimes ceramic coated to maximize friction (best in wet conditions.) Disc brakes on bicycles are scaled down versions of motorcycle brakes (or any disc brake for that matter)…a completely different set of materials when compared to rubber on aluminum. A ZTL brake is not analogous to a bicycle brake other than the transmission of braking forces. If motorcycle brakes consisted of rubber pads clamping the aluminum rims, there would be a marked difference in braking performance there too. Disastrously so. Imagine stopping sportbike going 120 mph with a few square inches of rubber on aluminum. Although the wheel may still be heavier overall, a rim for a bicycle wheel that does not have to be used for braking can be lighter than one that is used as a brake. Moving the mass down the hub is actually beneficial in that you reduce the polar moment of inertia, making that wheel easier to stop, start, or redirect, in much the same way that mass centralization makes our Buells handle better. Yes, someone could develop a ZTL bicycle brake that uses a stainless steel disc mounted at the rim, and it could be lighter, but it would not be durable enough at the same time. To be lighter that what is used today, it would simply be too flimsy, given the diameter of the wheel and the thickness required to get down to a weight less than that of today’s best hub mounted bicycle disc brakes. The braking power would be outstanding though, with that much mechanical advantage and friction area. | ||
| Freezerburn |
To summarize why disc brakes are superior: 1. You can easily ride out a non true rim and still have brakes. 2. The rim is engineered without having to double as a braking surface. 3. Brake pads for rims have short life spans. 4. Rim braking systems have poor modulation (even if hydraulic i.e. Magura) 5. One finger lock-up power for hydraulic disc systems. (i.e. all the power you need) 6. A properly built wheel can last years in extreme conditions - unless you're me. 7. Disc systems do not increase rotational mass of wheel significantly (but do slightly increase unsuspended mass). The only real detractors of discs is pad contamination (say you blow some fork oil and it somehow gets on your pads) and the risk of ripping out a brake line and losing fluid (if a fully hydraulic system). | ||
| Tramp |
You forgot the main reason for keeping rim-brakes off of ATBs- grit collects at the rims, as they tend to become submerged in mud, dirt and sand. | ||
| Cochise |
Speaking of Mountain bikes and brakes and rims, my brother, the brains of the family, was riding down a, uh, mountain road, he hit the brakes hard I'm guessing and his rim buckled and he went ace over tea-kettle and busted his un-helmeted head open on the pavement and rocks and had to get his head stapled with 15, and looked like a baseball. | ||
| Corporatemonkey |
My old man has a custom tandem recumbent bike. This is just part of his fleet of recumbents. Well I electrified it a few years ago, and had to replace the entire wheel assembly. We used hydraulic drum brakes. I have never seen them on another bike. |
