MTB vibration when braking hard
04-23-12, 03:18 PM
#1
Young wippersnapper
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MTB vibration when braking hard
Hello all
Keep noticing that when I brake really hard on my Land Rover MTB I get quite a vibration through the handlebars and was just wondering what it might be. It's not noticeable any other time, just right as the speed gets to about 10mph and still braking hard. Is it perhaps the tyre right on the limit of grip? These are cable discs BTW (details on link in sig.), so nothing too powerful, but I always keep them well adjusted.
Cheers
Keep noticing that when I brake really hard on my Land Rover MTB I get quite a vibration through the handlebars and was just wondering what it might be. It's not noticeable any other time, just right as the speed gets to about 10mph and still braking hard. Is it perhaps the tyre right on the limit of grip? These are cable discs BTW (details on link in sig.), so nothing too powerful, but I always keep them well adjusted.
Cheers
04-23-12, 03:33 PM
#2
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Hello all
Keep noticing that when I brake really hard on my Land Rover MTB I get quite a vibration through the handlebars and was just wondering what it might be. It's not noticeable any other time, just right as the speed gets to about 10mph and still braking hard. Is it perhaps the tyre right on the limit of grip? These are cable discs BTW (details on link in sig.), so nothing too powerful, but I always keep them well adjusted.
Cheers
Keep noticing that when I brake really hard on my Land Rover MTB I get quite a vibration through the handlebars and was just wondering what it might be. It's not noticeable any other time, just right as the speed gets to about 10mph and still braking hard. Is it perhaps the tyre right on the limit of grip? These are cable discs BTW (details on link in sig.), so nothing too powerful, but I always keep them well adjusted.
Cheers
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Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
04-23-12, 11:45 PM
#3
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It's probably brake judder. It may be related to a variety of issued from a warped disc to flex in the fork to a loose headset to the wavy rotors your bike came with. Check to make sure that headset is properly adjusted, that the brake caliper is tight, that there is no play in the fork's sliders and that the wheels are installed properly.
04-24-12, 07:58 AM
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While the forks may seem tight, the legs may be flexible. Under braking, the fork will bend backwards and the spring forward. It happens on all the bikes I've ever owned and it's worse on some of them...particularly the ones with thinner fork blades. The blades on your forks don't have as large a diameter as some forks and may judder more. Unless you are having control issues, I don't think you should worry too much about it.
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Plan Epsilon Around Lake Michigan in the era of Covid
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Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
Stuart Black
Plan Epsilon Around Lake Michigan in the era of Covid
Old School…When It Wasn’t Ancient bikepacking
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
04-24-12, 08:11 AM
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disc brake judder
I've had a few forks that really did this a lot. This issue seemed to be made worst with my Mech disc brakes rotor shape. The shape was called Roundagon and it seemed to grab while braking with a pulse that flexed the fork dramatically.
The round rotors seemed to brake smoothly and consistently.
Avid 185mm Roundagon Rotor Weight by aar0on, on Flickr
The round rotors seemed to brake smoothly and consistently.
Avid 185mm Roundagon Rotor Weight by aar0on, on Flickr
Last edited by cbchess; 04-24-12 at 08:16 AM. Reason: added more stuff
04-24-12, 08:45 AM
#6
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Interesting. The ones on the right here are mine, my Dad's round ones don't do it.
I've been through two sets of forks and it did it on both, so I'm guessing it is just the shape.
I've been through two sets of forks and it did it on both, so I'm guessing it is just the shape.
