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Discussion Starter · #1 ·
So over the weekend I was tailing to close to a buddy of mine as we were getting ready to make a left onto an entrance ramp and everyone stopped abruptly causing me to panic stop. I was only going 20 to 30mph max but what happened was the front end shuddered/chattered for a few seconds until I released the front brake. The rear tire never left the ground so it couldnt have been all that hard. Im wondering what could have caused that? Has that happened to anyone else? It skeered me a little because ive never felt that before. It was pretty loud to like a clicking sound. Felt like the front end was coming loose but everything feels tight and I tried to duplicate it and could not. Almost like the tire was skipping and grabbing really fast instead of sliding?

Anyone know how normal that is, if at all?
 

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Not normal, I don't recall it ever happening to me. Not sure what would cause an 09 to do it. What as the pavement like where it happened?
 

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Happened to me on a quick stop, but only once so far... maybe some kind of pogo effect due to the suspension? I was hard on the rear brake at the same time when it happened to me.
 

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Discussion Starter · #5 ·
Happened to me on a quick stop, but only once so far... maybe some kind of pogo effect due to the suspension? I was hard on the rear brake at the same time when it happened to me.
I might have been hard on the rear brake too. I dont remember because it happened so fast but I was taught to use both and usually do. Glad im not the only one to experience this though. I was afraid my bike was broken lol. My suspension was at factory settings. I just went full tight on damping and rebound tonight. Didnt get to take it for a test ride though. How was your suspension set when it happened to you? Pogo effect pretty much dead on explains it.
 

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Discussion Starter · #6 ·
how much fork travel do you use?
loose steering head bearings?
Dunno how to measure fork travel. Everything was still at factory settings when this happened. I dont think the steering head is loose either. Ive had a bike with loose steering head bearings and I could feel it every time I hit a bump or pulled the front brake lever. Bike only has 600 miles on it too.
 

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I might have been hard on the rear brake too. I dont remember because it happened so fast but I was taught to use both and usually do. Glad im not the only one to experience this though. I was afraid my bike was broken lol. My suspension was at factory settings. I just went full tight on damping and rebound tonight. Didnt get to take it for a test ride though. How was your suspension set when it happened to you? Pogo effect pretty much dead on explains it.
Mine was still factory, but it was the first time I really honked on the brakes when I thought I was going to overshoot my turnoff.
 

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Discussion Starter · #9 ·
Mine was still factory, but it was the first time I really honked on the brakes when I thought I was going to overshoot my turnoff.
Yeah this was probably the hardest ive braked too. I hope tightening up the suspension solved it. Or atleast I hope it never happens again!
 

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Were your tires cold (ie start of ride)? What tire pressure are you running?
 

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Discussion Starter · #12 ·
Were your tires cold (ie start of ride)? What tire pressure are you running?
I had been riding for about 20 mins and it was close to 90deg. Bike had sat for a few hours after a 100 mile ride so probably not cold. Front and rear 31 to 32 psi all depending on how accurate my gauge is.
 

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Discussion Starter · #14 ·
Just found this on the web searching for pogo during hard braking. I wonder if i don't have the correct amount of shock oil.


"A lack of oil in the forks or shocks will give the handling a pogo stick affect and will adversely affect the bike’s cornering ability. Also, as the compression damping will be less effective, the forks will dive more than normal under heavy braking".
 

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Rear brake shouldn't be an issue, Keith Code isn't main stream about that.

Your weight under hard braking is enough to max out the stock suspension, with the rough pavement the wheel probably couldn't follow the surface anymore, was on the edge of lock up, rapidly grabbing and skidding.

A bit stiffer springs and thicker oil should help.
 

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Dunno how to measure fork travel. Everything was still at factory settings when this happened. I dont think the steering head is loose either. Ive had a bike with loose steering head bearings and I could feel it every time I hit a bump or pulled the front brake lever. Bike only has 600 miles on it too.
Put a zip tie around the fork leg. It will be tight enough to stay put, but loose enough to slide down when the forks compress. It will tell you if you are maxxing out the suspension travel, which can cause chatter.
 

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It was that white rough pavement.
Guesstimate was the rough surface caused an unwanted but non-self correcting oscillation on your front parts, which is seriously already underdamped for riders over 170 pounds.

PS. whats the temperatures there? higher temps = less damping as the viscosity drops (ie fork oil becomes "watery")
 
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