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PostPosted: Thu Sep 13, 2007 13:15 
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Big Tone wrote:
I can't see the make Ed, it looks more like a Cannondale to me :)

Nice leg development by the way ;) Looks like you're at the front wining - or did you doctor the picture with software :lol:


the S on the front is a bit of a giveaway :wink:

that photo is the start of lap 3 out of 3.
the leader (but not the winner) overtook me on what was my lap 2 about 15minutes earlier :roll:


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PostPosted: Thu Sep 13, 2007 13:29 
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Big Tone wrote:
Something like that may have been the cause of the initial instability before I grabbed the brake? I could be on to something here methinks.


I definitely think fork flex. Certainly not frame flex as suggested in one of the linked articles.

It's interesting that the manufacturers thought fork flex for a (possibly?) related problem.

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PostPosted: Thu Sep 13, 2007 13:39 
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Big Tone wrote:
Something like that may have been the cause of the initial instability before I grabbed the brake? I could be on to something here methinks.


It may be wheel balance – or lack of it. I suspect it’s a combination of several things.

In my case, I really couldn’t say what set it off, but I’m convinced that it was exacerbated by my (virtual) lack of contact with the bars. Normal contact would, I imagine, damp out the effect before it got going.

You say you were ‘just holding’ the bars… How loose a grip was that?

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PostPosted: Thu Sep 13, 2007 13:47 
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Grumpy Old Biker wrote:
Big Tone wrote:
Something like that may have been the cause of the initial instability before I grabbed the brake? I could be on to something here methinks.


It may be wheel balance – or lack of it. I suspect it’s a combination of several things.

In my case, I really couldn’t say what set it off, but I’m convinced that it was exacerbated by my (virtual) lack of contact with the bars. Normal contact would, I imagine, damp out the effect before it got going.

You say you were ‘just holding’ the bars… How loose a grip was that?



Mark Haylett did say the forks were the source of it but I don't really like the idea of a 'fix' which isn't going to cure the inherent weakness or poor design. It feels a bit like the joke about 'I couldn't fix your brakes so I made your horn louder'.

My grip wasn't all that strong, until it started and then it became very strong but like I say, in a panic situation it's not easy to relax.

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PostPosted: Thu Sep 13, 2007 14:50 
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Big Tone wrote:
Mark Haylett did say the forks were the source of it but I don't really like the idea of a 'fix' which isn't going to cure the inherent weakness or poor design. It feels a bit like the joke about 'I couldn't fix your brakes so I made your horn louder'.

My grip wasn't all that strong, until it started and then it became very strong but like I say, in a panic situation it's not easy to relax.


It does shake your confidence - I didn't quite trust the bike for about 6 months after the event. Mind you, I tend not to ride down hill with 'no-hands' anymore.... :D

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PostPosted: Thu Sep 13, 2007 15:56 
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Grumpy Old Biker wrote:
Big Tone wrote:
Mark Haylett did say the forks were the source of it but I don't really like the idea of a 'fix' which isn't going to cure the inherent weakness or poor design. It feels a bit like the joke about 'I couldn't fix your brakes so I made your horn louder'.

My grip wasn't all that strong, until it started and then it became very strong but like I say, in a panic situation it's not easy to relax.


It does shake your confidence - I didn't quite trust the bike for about 6 months after the event. Mind you, I tend not to ride down hill with 'no-hands' anymore.... :D


i assumed he was trying to do the superman position :wink:


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PostPosted: Mon Sep 17, 2007 08:32 
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I was in a cycle shop in Kenilworth the other day talking to a very learned man. He said they've had a similar problem: -

A man once brought back a Trek bike for the same reason as myself. A shop assistant rode the bike and found it to be fine, doing the same speed etc., however, the shop assistant and the purchaser were built very differently.

He told me that the purchaser was a larger man and they concluded that he would have been loading the front end of the bike considerably more than the test rider.

It makes sense to me that if more of the weight is over the front end it will adversely affect the handling.

Now I have to mention that I am a funny shape. I have been weight training since I was about 13 years old. My legs aren't huge but my upper body is comparatively large. I'm 14 stone with a 47 inch chest. I rep on the bench press with 140 kg, (about 300lb), so basically I'm very top heavy. I can't do sit ups without my legs coming off the floor or in other words I'm not an ideal cyclist's body type. ie. just a pair of legs and lungs.

Now I think this very relevant if indeed having too much weight on the bars or towards the front end affects the handling to the degree I experienced.

So I hope this is interesting or informative for others. I'm sure this is at the core of the problem, along with the carbon fibre forks. I'm convinced that if someone else rode my bike they most likely wouldn't have a problem with it.

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PostPosted: Mon Sep 17, 2007 10:22 
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..well there's only one bike shop in kenilworth.


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PostPosted: Mon Sep 17, 2007 10:34 
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ed_m wrote:
..well there's only one bike shop in kenilworth.


Yep, so I believe. Nice place, family owned I think. I saw the main-man's son who was very knowledgable. It was he who told me all this.

Like I say, your body weight and shape must make a significant difference to the handling of any bike. I'm certain now that the combination of this bike with my body is not suitable :(

I'm hoping to get back to the shop I brought mine from this Friday, my flexible day off, and change it for a mountain bike. I know that will be safer for me, even if not as fast.

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PostPosted: Wed Sep 26, 2007 17:25 
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Epilogue: -

I took the Tricross back yesterday and swapped it for a Stumpjumper Expert. I just had to pay the difference to upgrade, it's a £1500 bike. (Yep, more money than sense but like I say, I expect to keep it for a very long time - hopefully)

I feel a lot safer now; may change the tyres for road ones though. It looks like it's got motorbike tyres on at the moment and I don't like the feel of them although I'm sure they're excellent in the woods.

The old Tricross has gone back to Specialized.

Maybe now I can work to remove the blubber that's acumilated around my gut...

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