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-   -   Stop Front Brakes Locking Mechanically (other than by improving braking technique) (https://www.bikeforums.net/mountain-biking/998147-stop-front-brakes-locking-mechanically-other-than-improving-braking-technique.html)

timtak 03-14-15 08:35 PM

Stop Front Brakes Locking Mechanically (other than by improving braking technique)
 
I see that there are things that one can put in the brake line
http://www.bikeforums.net/hybrid-bic...l#post15659618
http://www.bikeforums.net/hybrid-bic...l#post15659186

What are they called and where can I purchase them from China?

Are there some poor brake pads I might use to prevent locking?

Can I just adjust the front brakes so that they do not work so well?

Will using thinner front tires help? (I think I can handle some skidding, it is the insta-stop that gets me)

The problem may be that the suspension runs out of travel and when that happens ones full weight is suddenly on the front wheel and there is a sudden increase in braking power, causing locking and facepavementing. In other words, I already have *okay* braking technique from my roadbike experience, but do not know how to modulate my braking to take account of this moment-when-the-suspension-runs out.


Background
Two times in the recent past, I have locked up my front brakes on a mountain bike and flipped face to tarmac/pavement or got enough air under my rear wheel to scare me shirtless. I only use moutain bikes when renting them. Many rental shops only rent out mountain bikes. I won't be getting the practice in to improve breaking technique. I am looking for a way of modifying MTB front breaks to make them a little less effective so that I do not lock up my front brake. They were V-Pull brakes, and seem to stop on a pin.

The first bike had a frame which was too small, so I made shure that I had a large frame, and I swapped the stem for a longer one to put my weight backwards. However, a car pulled out in front of me, I braked in plenty of time, but fell when my rear wheel left the ground. I sort of made myself fall to the side since I did not want to facepavement again.

Facepavement photo
https://www.flickr.com/photos/nihonbunka/8015375727/

osco53 03-15-15 05:45 AM

That's a hard question,, so so many variables,,,

The simple stuff,,

Clean the wheel rims and check for cracks or rough spots (Rims can wear right through)...
They can be sanded smooth sometimes...

New pads if the old ones are badly contaminated or worn, they often get brittle.
Set the pads with 'Toe In' Use a credit card, Inserting it about 1/3 of the way into the rear of the pad then tighten it down.
This makes the front of the pad hit first and harder, often eliminating sudden bite and noise......

Pull the cables out and If they are in good shape sand them smooth with emery cloth or 800 grit made for metal..
Any kinks or rust change them,,,
Re lube with a thin oil and seal each housing end with a dab of thicker grease to keep the moisture out..

Got the little bit of extra money replace with teflon coated cables,,
way smoother they are. IF you do These teflon cables DO NOT LUBE at all !

Incorrect adjustment,,could be but I can't see them..

Are you using BOTH brakes ALL the time ? you should be.....
To help Bias more power to the rear, use one finger on the front and two on the rear.......


Oh yeah,, WEAR A HELMET before you kill yourself,,,,

spdracr39 03-15-15 07:11 AM

Yes you can adjust the cable tension on the front so that it takes a longer pull to lock them up. This will at least get the back brakes to engage first. Having said that there is no "fix" for improper technique and you can't design out the skill needed by the rider. If you really want to ride better and safer you need to practice and train in less dangerous riding conditions until you learn how to brake properly. There is no replacement for this.

osco53 03-15-15 03:41 PM

If your constantly riding in wet or muddy conditions then rim brakes are not the best option.

Save up some coin and get a bike with 'Wet' brakes... Hydro's,,they modulate really well like motor cycle brakes, so much control.

gsa103 03-16-15 07:56 AM

Get your butt backwards off the seat, and lower your chest. You need to shift your weight backwards. A longer stem shifts your weight forward making the problem worse. You want a short stem and wider riser bars, then lower your seat about an inch compared with a road bike.

The vast majority of road riders have terrible braking technique, which works because they also have terrible brakes. Having seen pictures of your road position, using a similar setup on a mountain bike is a guarantee you go over the bars.

Bholio 03-16-15 06:54 PM

What kind of brakes are on the rental bike?

If it has hydraulic discs and you are used to rim brakes, you simply need to take some time and get used to them. They stop with very little hand pressure compared to caliper brakes.

And you don't want a little skidding with the font wheel. That's an instant fall.

timtak 03-17-15 12:57 AM

Thank you very much everyone. Sorry I am late to respond. I forgot to subscribe.

I like the idea of the toe in adjustment and new pads suggested by osco53 & I will take pads with me next time.

These were v pull brakes. I a talking about rental bikes. I don't think I have the option or expertise to fit hydros or disks.

I think that gsa103 has a very good point. I should have used a short stem NOT a long one. I think I do want to lower my chest though (that facepavement was in an upright position) so I may purchase an adjustable stem to get lower without getting further toward the front.
Adjustable Road Mountain Bike Stem Aheadset Stem SP138-in Bicycle Stem from Sports & Entertainment on Aliexpress.com | Alibaba Group

Kindaslow 03-17-15 07:29 AM

Like some of the others, I am stuck with believing technique should be the focus. I cannot imagine squeezing rim brakes, especially wet ones, hard enough to endo. Some of the changes will help, but technique will likely still need to be focused on.

gsa103 03-17-15 10:37 AM

This video seems highly relevant to the situation. Its an article on braking technique for bicycle police, which would be similar to your riding style.


And yes, it's entirely possible to endo wet rim brakes. I've personally done it when I suddenly grabbed the lever to talk to a friend and I wasn't paying attention. Next thing I knew I was going OTB at low speed.

Your suspension should not be running out of travel from braking, if it is, you have the suspension set WAY too soft. A soft suspension will also amplify brake dive and make it easier to go over. If the bike has an air fork, you may want to consider upping the pressure.

timtak 03-17-15 05:52 PM

Nice video. But when you are about to be hit by a car, do you remember to put your butt back? I think that it would take a lot of practice for me to avoid clutching my brakes brakes first, and bashing my brain again.

I would rather be in a position with weight distributed and brakes adjusted in such a way as to make endo impossible especially since I do not own a mountain bike and only use the rental. I would need to buy one to practice on and then practice quite a bit. I knew everyone was going to say "technique," but bearing in mind that I don't have a bike, it is only for one or two weeks a year when on a rental, I did specifically ask for non technique options.

I never endo my road bike (I think it impossible) "because the brakes are so bad" and that suits me fine. Is there no way to make mountain bike brakes as "bad" as road bike brakes? (That plus position)

What about those springs that I link to in the original post?

I also note that the policeman has an upright position. People may know that I am into long and low and this seems to prevent not promote endo. My facepavement was from a position like the policeman: fast flip forwards, forehead into ground.

I don't think that the rental bikes have air suspension. Rental bikes tend to be cheap.

LesterOfPuppets 03-18-15 01:12 PM

Installing brake attenuators sounds like a pain in the ass.

Just practice emergency stops from an upright position. Push yer ass off the saddle and plant that saddle into your chest.

Also, learn to do stoppies. Rear wheel leaving the ground is nothing to worry yourself about if you get used to it happening.

Here's an inspirational video of mostly regular wheelies and manuals but also some impressive nose manuals:

https://youtu.be/7yO0M_OaHZc?

slowride454 03-18-15 02:55 PM

disconnect the front brakes. pretty simple. most of us grew up with only a coaster in the back and lived.

gsa103 03-19-15 11:00 AM

Have you tried using the front brake cable adjuster to open the calipers farther? That way the lever would go almost to the bar before you got full braking force.

timtak 03-19-15 05:37 PM


Originally Posted by slowride454 (Post 17641628)
disconnect the front brakes. pretty simple. most of us grew up with only a coaster in the back and lived.

Interesting. I could do that but I think that this next idea is what I will try first.

Originally Posted by gsa103 (Post 17643954)
Have you tried using the front brake cable adjuster to open the calipers farther? That way the lever would go almost to the bar before you got full braking force.

No I have not. I will try this.


Originally Posted by LesterOfPuppets (Post 17641266)
Installing brake attenuators sounds like a pain in the ass.

Ah, now I know what they are called. I still can't source them from China, nor know how they are installed. If they are a pain in the ass, then I will not be able to install them because I am poor mechanic.


Originally Posted by LesterOfPuppets (Post 17641266)
Just practice emergency stops from an upright position. Push yer ass off the saddle and plant that saddle into your chest. Also, learn to do stoppies. Rear wheel leaving the ground is nothing to worry yourself about if you get used to it happening.

I don't have a mountain bike but I suppose I could devote the first x amount of time after I rent to practice. Hypothetically, how many hours do you think it would take before I learnt NOT to grab ones brakes in an emergency, and to do "stoppies" (I think that last time I feel off I would have just done a stoppie but I panicked). I think I learn less fast now that I am 50.


Originally Posted by LesterOfPuppets (Post 17641266)
Here's an inspirational video of mostly regular wheelies and manuals but also some impressive nose manuals: https://youtu.be/7yO0M_OaHZc?

Inspirational, perhaps. But i just can't see me and rental bike in any connection with that video.

gsa103 03-19-15 06:09 PM


Originally Posted by timtak (Post 17645002)
I don't have a mountain bike but I suppose I could devote the first x amount of time after I rent to practice. Hypothetically, how many hours do you think it would take before I learnt NOT to grab ones brakes in an emergency, and to do "stoppies" (I think that last time I feel off I would have just done a stoppie but I panicked). I think I learn less fast now that I am 50.

You don't have to spend a lot of time practicing, but you should definitely do a set of progressively harder stops each and every time you get on a new bike. That way you'll have some idea of how the brakes on that bike behave.

timtak 03-19-15 06:34 PM


Originally Posted by gsa103 (Post 17645072)
You don't have to spend a lot of time practicing, but you should definitely do a set of progressively harder stops each and every time you get on a new bike. That way you'll have some idea of how the brakes on that bike behave.

Thank you. Good idea.

cpach 03-23-15 01:38 AM

Gimping your brakes is a ridiculous solution. I am surprised that you don't think it's possible to endo on your road bike. With decent dual pivot road brakes, this is easy to accomplish from a bad position, and possible to accomplish even from the best braking position.

I'd recommend you practice braking technique on one of your road bikes. For maximum effect, practice from the drops. Bring your weight back and drop your center of mass, feel like you're pushing your heels down and brace your upper body. While it's possible to generate enough braking force to endo a user with even the very best technique, most people endo because their upper body travels forward as the bike decelerates putting the center of mass further forward over the front wheel. Do this progressively harder until you begin lifting the rear wheel. Also try this from the hoods. I suspect a couple half hour sessions of practice would be a good way to get a feel for this skill, then occasionally practice hard braking in safe circumstances during ordinary riding.

And, yeah, I DO do this instinctively because I practiced--and I did it way before I bought a reasonable mountain bike. The maximum braking speed for a bicycle is with the weight of the rider as low and as far back as possible, with the body braced against deceleration, and with so much force that the rear wheel is almost beginning to lift. This is an important skill because it can make the difference between running into that car that pulled out in front of you or not, etc.

You do need to recalibrate for any braking system you're not familiar with. Doing progressively harder stops is standard operating practice to get used to differing levels of modulation. I do remember being amazed the first time I demo'd a $7000 all-mountain bike with Shimano XTR brakes--the power was THERE much sooner into the lever travel than I expected. Did one endo at super low speed trying to slow down to observe an obstacle. But really I got used to the thing in like 30 minutes and then life was amazing.

timtak 03-23-15 02:01 AM

Gimping brakes is a solution employed by Shimano I believe, and commended on the thread I link to above, where it is described as "ABS for bicycles" (on a linked YouTube video).
https://www.youtube.com/watch?v=1F6mP7a9svM
I am not sure how good it is.

I did not mean to ask about braking technique, and made that as plain as I could in the title of this thread. I am aware that practising braking technique is the ideal, but not the only, way forward.

Incidentally however, while out riding my road bike recently I realised that I already instinctively employ the centre of gravity back technique when braking on my road bike.

You are no doubt right that it is possible to endo a road bike. I have never done so, no feel in danger of so doing due to my technique and a variety of factors (tire width, braking power, position etc).

I think that the problem for me with mountain bikes is not only in their superior braking but also in some interaction with the suspension that made/makes modulation more difficult, requiring more practice. Bearing in mind my lack of a bike to practice with, the use of some mechanical aids (position adjusting, brake power adjusting, modulating, tire changing) seemed, and seems, to make sense to me.

cobba 03-23-15 02:37 AM


Originally Posted by timtak (Post 17631266)
I see that there are things that one can put in the brake line
http://www.bikeforums.net/hybrid-bic...l#post15659618
http://www.bikeforums.net/hybrid-bic...l#post15659186

What are they called ?

They're called Power Modulators.

http://productinfo.shimano.com/#/spe...er%20Modulator

timtak 03-23-15 02:39 AM


Originally Posted by cobba (Post 17653512)
They're called Power Modulators.

2015-2016 SHIMANO Product Information Web

Thank you.

LesterOfPuppets 03-23-15 08:51 AM

They're primarily designed for people who only ride their bikes once or twice a year, 4 miles on the MUP

timtak 03-23-15 10:06 AM


Originally Posted by LesterOfPuppets (Post 17654136)
They're primarily designed for people who only ride their bikes once or twice a year, 4 miles on the MUP

http://www.bikeforums.net/commuting/...-mup-mean.html

That's me.

Except I was riding on a hard shoulder and it is not my bike.

DiscTruckerMF 03-23-15 11:21 AM


Originally Posted by timtak (Post 17639039)
Nice video. But when you are about to be hit by a car, do you remember to put your butt back? I think that it would take a lot of practice for me to avoid clutching my brakes brakes first, and bashing my brain again.

I would rather be in a position with weight distributed and brakes adjusted in such a way as to make endo impossible especially since I do not own a mountain bike and only use the rental. I would need to buy one to practice on and then practice quite a bit. I knew everyone was going to say "technique," but bearing in mind that I don't have a bike, it is only for one or two weeks a year when on a rental, I did specifically ask for non technique options.

I never endo my road bike (I think it impossible) "because the brakes are so bad" and that suits me fine. Is there no way to make mountain bike brakes as "bad" as road bike brakes? (That plus position)

What about those springs that I link to in the original post?

I also note that the policeman has an upright position. People may know that I am into long and low and this seems to prevent not promote endo. My facepavement was from a position like the policeman: fast flip forwards, forehead into ground.

I don't think that the rental bikes have air suspension. Rental bikes tend to be cheap.

you seriously need to learn how to ride a bike man. Quite frankly, yes, if a car was about to hit me, I would think to move my weight back as I jammed on my brakes. the notion of intentionally having bad brakes that dont work properly is utterly stupid to me. If the brakes are that bad that you won't endo, it means they also won't stop you when hurtling downhill at 20 or30+ mph
rental bikes could have air suspensions, there are plenty of cheap air forks and as others said, if its fully compressing all the way to the bottom out position just from braking, you have a broken fork

timtak 03-23-15 01:27 PM


Originally Posted by DiscTruckerMF (Post 17654615)
you seriously need to learn how to ride a bike man. Quite frankly, yes, if a car was about to hit me, I would think to move my weight back as I jammed on my brakes. the notion of intentionally having bad brakes that dont work properly is utterly stupid to me. If the brakes are that bad that you won't endo, it means they also won't stop you when hurtling downhill at 20 or30+ mph.
rental bikes could have air suspensions, there are plenty of cheap air forks and as others said, if its fully compressing all the way to the bottom out position just from braking, you have a broken fork

Perhaps I should not rent a mountain bike or ride it at speeds where I can endo. I accept that possibility.

Spending my holiday learning mountain bike braking Technique is not an option that I wish to consider here at least.

The trouble is I was going pretty slowly. Mountain bike brakes are so much more powerful than road bike brakes. Shimano makes a device to attenuate (selectively weaken) their power. It is options of this kind that I am seeking.

I am not sure why the suspension made braking, for me, more difficult.The forks were not broken. Perhaps it was rather that the give of the suspension hid from my untrained roadie hands the fact that my wheels had locked. So perhaps I should bring some suspension-less front forks.


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