Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

Mountain Biking Mountain biking is one of the fastest growing sports in the world. Check out this forum to discuss the latest tips, tricks, gear and equipment in the world of mountain biking.

User Tag List

Reply
 
Thread Tools Search this Thread
Old 04-25-14, 04:28 PM   #1
zkcmurphy
Newbie
Thread Starter
 
Join Date: Apr 2014
Bikes:
Posts: 2
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
pulsing when front brakes applied

Hi people,

I'm getting into biking these days and have acquired a Kona Lanai Mountain bike from my cousin. It is a year old. When I apply the front brakes, the bike shutters/pulses. most noticeable at higher speeds, especially going downhill (road, not trail). I've examined the front wheel to see if it is warped (not true). It looks good. the bike has disc brakes and front suspension.

Any ideas? I wanted to try fixing the problem myself before going to a bike store/shop.
zkcmurphy is offline   Reply With Quote
Old 04-25-14, 04:33 PM   #2
jimc101
Senior Member
 
Join Date: Oct 2007
Location: West Yorkshire, United Kingdom
Bikes:
Posts: 5,101
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 131 Post(s)
Check the (a)headset, is this correctly adjusted, as if not, it could product the situation being described.
jimc101 is offline   Reply With Quote
Old 04-25-14, 05:26 PM   #3
zkcmurphy
Newbie
Thread Starter
 
Join Date: Apr 2014
Bikes:
Posts: 2
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I will check that out. I youtube'd how to service the headset. Seems simple; we will see.
zkcmurphy is offline   Reply With Quote
Old 04-25-14, 07:02 PM   #4
Grimlock
Frozen in carbonite
 
Grimlock's Avatar
 
Join Date: Oct 2004
Location: Ottawa
Bikes: '85 Full Cycle Cycle.
Posts: 805
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
It could be a dozen different things, from a warped rotor to play in the fork stanchions. Instead of fiddling with the headset or doing something silly like putting lube on the rotor, bring it to a shop you trust for a diagnosis. It should be as simple as a tech taking it for a spin for them to tell you what the issue is. As long as it's not too busy, they may be able to do it on the spot.
__________________
Quote:
Originally Posted by sp00ki View Post
Using a nicer sealed bearing headset vs a $10 set is like throwing a frisbee vs a dodgeball.
Grimlock is offline   Reply With Quote
Old 04-26-14, 09:04 AM   #5
ncfisherman
Senior Member
 
ncfisherman's Avatar
 
Join Date: Mar 2011
Location: Chapel Hill
Bikes: Canfield Yelli Screamy, Pivot Mach5, Specialized Roubaix, '65 Hercules, '79 Schwinn Stingray Lil Chic, '68 Schwinn Stingray Fastback, '89 Specialized Allez Epic, '86 Battaglin World Champion
Posts: 457
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
It could be as simple as fork flex. It's going to be more noticeable with standard QR dropouts, like on your fork, when combined with disc brakes. This wasn't an issue for QR dropouts when bikes came with v-brakes, but the added power of a disc added to the lower leg is going to make flex in that area much more noticeable, especially in the high speed conditions you describe. If you're a heavier rider, it's even more noticeable. I tried to ride a rigid QR fork a few years ago and gave it up because of the excessive flex.
ncfisherman is offline   Reply With Quote
Old 04-26-14, 10:53 AM   #6
frankenmike 
mechanically sound
 
frankenmike's Avatar
 
Join Date: Jan 2007
Location: Dover, NH
Bikes: Indy Fab steel deluxe, Aventon cordoba, S-works stumpy fsr, Masi vincere, 92 Hardrock commuter, Dahon mu uno, Outcast 29
Posts: 1,437
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 29 Post(s)
Sounds like a cracked rim to me.
__________________
frankenmike is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -6. The time now is 01:38 PM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    get answers from real people!
Click to start entering your question.
I HAVE A QUESTION