canklecat

Go-fast is fun, but braking is a whole nuther thing. Especially with really strong brakes like discs.

GCN has some good video tutorials for braking techniques to practice -- preferably safely, away from traffic and other cyclists.

One tip that's difficult to remember consciously, so we need to practice until it's instinctive -- shifting our weight back to compensate for hard braking. I nearly went over the bars a couple of times when I resumed cycling a few years ago, braking hard on unexpected stops on downhills to avoid errant vehicles and dogs. And did go over the bars while practicing hard braking. Fortunately I was practicing on grass, not thinking the tires would dig in enough to lock up. Wrong. But because it was soft grass, no damage or injuries.

And if you change anything, especially tires or brake pads, test again.

PeteHski

Okay, so I presume you didn't have this issue at all with your previous Trek? Just trying to work out if it's a lack of experience or a bike specific issue.

BforumBMC

Have had two previous bikes. A Giant and a Trek and I have never experienced any issues with either bike such as the ones I have recently encountered hence my thoughts that maybe there is an issue with the bike. However, the more I read the more questions re my bike handling. I will get the bike checked out however, as some issues have arisen from posts here.

I have recently replaced tyres and had brake pads replaced by the by technician. As mentioned, the bike has been regularly serviced.

63rickert

You are 76 years old. Your reflexes are slower. You are not a lifetime rider and you do not have locked in muscle memory for descents.

Now you are going fast downhill on a race bike. What do you expect is going to happen? This thread has some good suggestions. Using any of those suggestions at full speed is not a good idea.

You are riding with a group? Can’t they help you? If you can’t trust your group for the sort of help you are asking for on this thread do not get within a quarter mile of that group on a descent.

njkayaker

It might be useful to know the models of the other bikes.

I suspect you might be going faster on the BMC and using the brakes harder. If so, then you are talking about different situations (where different things might happen).

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RAFSteve1

Tank slapper comes to mind, which if anyone has ridden a 1970s Japanese motorcycle, may have experienced. Not sure what reason a tank slapper used to happen but it may well be the geometry of the bike, or frame damage or fork headset damage maladjustment along with tyre pressure anomalies. All would contribute to dodgy handling. I hope you get it sorted out, falling at your age could be terminal? I was 65 last week and wouldn't fancy falling off at speed.
All the best in your recovery. Steve.

jpdemers

My first thought as well: on a fast turn, braking the front wheel applies a force to the fork that's at an angle to the direction of motion. The physics are beyond what I care to thrash out here. It's possibly due to a combination of brake materials and fork geometry, but the bottom line is "positive feedback". If you use only the rear brakes, it should not affect the steering, nor cause the front fork to shimmy. I'd use the front brakes sparingly, rather than risk locking up the rear wheel, in a heavy braking situation, but one shouldn't need to brake that heavily under normal circumstances. If you do, your speed is not just high: it's dangerously high.

Bill Abbey

okay. I've had this happen several times. Its unnerving. Its related to weight over the front wheel and fork. It can be immediately relieved by squeezing the top tube with your knees, probably because your weight forward goes from the handlebar back towards the seat. IF you have a front handlebar bag I suggest you lighten its load. Check the headset in any case. Since all weight is forward, the rear wheel has little or no load and its all on the fork and the trail. A slight shimmy spreads up and back and becomes lots of flexing. No fun. In my case it means that my hands sweat and my ******* clamps in to the S H U T position for at least one hour.

aclinjury

You seem to hint that tank splapper only happens to Japanese motorcycles form the 70s? Ever watch any motorcycle race of today? Tank slappers happen a lot.

aclinjury

OP, ask someone younger to test ride your bike and see how he feels. If he says this bike cannot handle, then it's the bike. If he has no issue riding the descent you describe, then it's you, in which case it's time to avoid that road.

SkinGriz

I’ve done it on newer bikes, but I think it was more common on older more flexible bikes.
The bike has 3 gyros and doesn’t really want to shimmy.
Usually the rider is too tight on the bars and is the cause of it. Gripping too tight so his own forearm muscles will be like springs.

SkinGriz

I’m want to be hauling ass down hills when I’m 76.

ryanl092

I remembered I barely break in the corner. Normally break before the corner as I learned from car and motorcycles.
With car and motorcycles we can accelerate during the cornering, but bike has it's limitation of paddle hitting the ground.
I mean I would press a bit throttle when I feel tail is drifting out when driving.(I can't handle motorcycle that well when I was young)
With Bike I am a bit scare to do hard brake during the cornering.