MichaelKatz
friend
Reged: 12/19/03
Posts: 26
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I have both a Seven Axiom Ti and a Spectrum Ti Superlight that have remarkably similar geometries but which have very noticable and distinctive differences in handling characteristics.
The Axiom gives me the stability I wanted but feels like this is at the sacrifice of quick and responsive handling. I feel like this is due to the Seven being built with a higher center of gravity and slight understeering at the front end. I feel like I am sitting on top of the Seven and not immersed into the cockpit.
The Spectrum is a much more responsive handler yet is as stable as the Seven. With its 1" chainstays, it feels stiffer through the bb and drivetrain. It has an aggressive upper body position (I feel immersed in the cockpit) but yet is ergonomically more comfortable on long rides. It feels like a performance machine tuned to the ergonomics of my body.
The kicker is, here are the specs on the 2 bikes:
Seven -
TT length c-c =54.8, 2 degree slope
ST length c-c =52.5
HT length = 14.8
HT angle = 73
ST angle = 73
BB Drop - 7 cm
Stem - 11cm, +10 degree
Chainstay - 41 cm
Fork Rake - 45mm
Spectrum -
TT length c-c = 55.2, 3 degree slope
ST length c-t = 56 (54 c-c?)
HT length = 13.3
HT angle = 73
ST angle = 73
BB Drop = 7.5
Stem - 10 cm, +10 degree
Chainstay - 41.5cm
Fork Rake - 45mm
At first blush, stats don't seem to explain handling differences but my Spectrum is the clear winner in the responsiveness department and is stable as hell during 50 mph descents! The forks on both are Wound Up. Any thoughts on why the distinctively different feel to the handling?
Edited by MichaelKatz (04/02/04 03:28 AM)
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Dave_Thompson
prophet
Reged: 12/19/03
Posts: 719
Loc: Spokane, Washington
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Quote:
It feels like a performance machine tuned to the ergonomics of my body.
That's why you paid Tom Kellogg the big bucks! But, as little as I know about the absolutes of bike handling and what makes it "right", I would suspect several things make a big difference. One would be trail, one would be front center and one would be chainstay length. I would venture a guess that these dimensions are somewhat different between the Seven and the Spectrum. And all things put together make the Spectrum 'your' bike. It's kinda like my Volvo that I bought last year. That car 'fits' me and has characteristics that make it feel that I am "wearing" the car rather than sitting in it. I can't tell you anything about what makes it so, but all things put together make it 'my' car. Does that make sense?
I guess what I'm trying to say is that there is no one feature or dimension that makes the Spectrum right, it's the 'whole' (to coin a phrase).
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Steel lover, but then I like Ti with carbon too.
Licensed bike geek.
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MichaelKatz
friend
Reged: 12/19/03
Posts: 26
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Thanks for the reply Dave. The Seven has a chainstay of 41 cm and the Spectrum 41.5.The fork rakr is 45mm on both and the BB drop on the Seven is 7cm. What is front center?
Thanks,
Michael
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kajukembo
new member
Reged: 12/19/03
Posts: 14
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I agree with the whole immersed in the cockpit theory. When I’m on my Spectrum it’s like the bike surrounds me. On my other bikes, I’m on top of them. It would be helpful to know the measurement from the bottom bracket to your front axle, but I suspect the difference is the intangible brought to the process by Tom. I have friend who owns a 15 year old steel Spectrum and we both agree that no one makes a bike like Tom. The front end geometry on the bikes I’ve seen by Tom are quite different and I believe somewhat explains the handling. When I first received mine, I rode at slow speeds and immediately noticed that the bike could be steered instead of just leaned. This makes for a very responsive ride. I was actually a bit concerned thinking that it would be loose at high speed. It turns out that it’s the most stable bike I’ve ever owned at high speed and under hard braking. How did he do that? Spectrum makes less than 200 bikes a year. Seven makes more than 2,000. Concerning your bike, it sounds as if Tom just nailed it and that’s a consistent Spectrum experience.
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lanton
new member
Reged: 02/11/04
Posts: 17
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I'm really glad to hear someone else talk about that steering quality, don't have a spectrum but it seems like some bikes have it and many don't. Before I'd ever owned a nice bike I picked up a beater road bike that appeared to have had a head on of some kind, you could see the slightly cracked paint on the top of the top and down tubes where they were slightly stretched, otherwise barely noticeable, and strangely, the fork seemed ok. As often happens with beater bikes it became my most ridden for a while and I loved the way it could maneauver at low to moderate speeds, (for example going up a very mild grade and being able to dodge little pieces of glass you didn't see until they're right in front of your face - almost effortlessly) and it didn't seem to have any problems at high speed, but I never pushed it. It did have some toe clip/front wheel overlap so the really low speed extreme steering was not convenient, and it was a damaged old bike anyway so it got given away to make way for newer better bikes. But I started missing that steering quality of my old beater and only ever heard that to get it would be at the expense of less stability. Anyway, comforting to think that someone seems to have it pretty figured out.
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kajukembo
new member
Reged: 12/19/03
Posts: 14
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I, just by chance, went down the highest speed decent within 40 miles of my house for the first time on my Spectrum. It’s a 3 mile completely straight decent with a couple of 15% sections. I’ve hit over 50 mph on this decent before and I’m not afraid to admit that every time it strikes fear. My Spectrum is clearly the most stable descending bike I’ve ever ridden. Slow speed steering, high speed stability. Nice combination.
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MichaelKatz
friend
Reged: 12/19/03
Posts: 26
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What I find to be so intriguing about my Superlight is that it not only has the stability you describe but also is a very responsive handling bike. It responds quickly to rider input but yet is never twitchy. It gives me the best of both responsive handling and stability without compromising either. It is clearly superior in this regard to all other bikes I have owned.
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kajukembo
new member
Reged: 12/19/03
Posts: 14
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Ssshhh, it's a secret. Where I live, Spectrums are mostly unknown. At the local races or group rides, everyone walks right by my bike and ogles the crappy riding Italian Aluminum bikes and the quasi custom Ti ones. It's kind of like being a parent, unless you've got one, you just don't get it. I'm glad you got one.
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