Racer Tech Thread
#4626
Grolby, woudn't "reluctance" to turn have more to do with the head tube angle than the BB drop? How do the head tube angles on your Ridley and other bikes you mention compare?
#4627
OMC


Joined: Oct 2010
Posts: 6,973
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From: South Louisiana
Bikes: Specialized Allez Sprint, Look 585, Specialized Crux E5 Sport, Trek Domane SL6
I think that chainstay length figures into that too, with a relatively longer one contributing toward stability.
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Chuck
Demain, on roule!
#4629
Senior Member


Joined: Feb 2007
Posts: 15,410
Likes: 189
From: Tariffville, CT
Bikes: Tsunami road bikes, Dolan DF4 track
I do think a high BB affects tip in, making it harder to tip in. For a few years Cannondale offered certain mountain bikes in two radically different BB height configurations, I want to say 10" and 12" high, the latter to make riding logs/etc easier (late 80s so no suspension yet). I had a 12" high one or whatever was taller. I could tell immediately when I was on a taller BB version or a shorter one. The difference was pronounced/exaggerated for sure, but I wasn't keen on the tall BB.
I find a short stay helps in out of the saddle, doesn't seem noticeable anywhere else. This going from 40.5 to 39 cm on the same frame, and switching between frames with 40.5 and 39 cm which have otherwise identical specs (top tube, head tube, etc). For a couple years my orange bike had a 40.5 cm stay, I got the black one with 39, then sent back the orange to be adjusted to 39 cm. No difference in the saddle, massive difference when sprinting out of the saddle. Cornering no diff.
Front center seems less significant also. My very long bike handles fine in corners.
Wheelbase - my orange bike was 102 or 103 cm, and now my bikes are about 100.5 cm. Normally a bike my height would be 97ish. No big deal.
I find a short stay helps in out of the saddle, doesn't seem noticeable anywhere else. This going from 40.5 to 39 cm on the same frame, and switching between frames with 40.5 and 39 cm which have otherwise identical specs (top tube, head tube, etc). For a couple years my orange bike had a 40.5 cm stay, I got the black one with 39, then sent back the orange to be adjusted to 39 cm. No difference in the saddle, massive difference when sprinting out of the saddle. Cornering no diff.
Front center seems less significant also. My very long bike handles fine in corners.
Wheelbase - my orange bike was 102 or 103 cm, and now my bikes are about 100.5 cm. Normally a bike my height would be 97ish. No big deal.
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"...during the Lance years, being fit became the No. 1 thing. Totally the only thing. It’s a big part of what we do, but fitness is not the only thing. There’s skills, there’s tactics … there’s all kinds of stuff..." Tim Johnson
"...during the Lance years, being fit became the No. 1 thing. Totally the only thing. It’s a big part of what we do, but fitness is not the only thing. There’s skills, there’s tactics … there’s all kinds of stuff..." Tim Johnson
#4631
OMC


Joined: Oct 2010
Posts: 6,973
Likes: 142
From: South Louisiana
Bikes: Specialized Allez Sprint, Look 585, Specialized Crux E5 Sport, Trek Domane SL6
I was wondering that too. Mine are 58s except for the Look 585 which is a 61 but measures the same as my other bikes, and the wheelbases are right at 100.
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Chuck
Demain, on roule!
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Chuck
Demain, on roule!
#4632
Senior Member


Joined: Feb 2007
Posts: 15,410
Likes: 189
From: Tariffville, CT
Bikes: Tsunami road bikes, Dolan DF4 track
73 deg HT angle, 43mm rake, so totally normal.
56.5 top tube jutting out of a seat tube that's at a 75.5 deg angle. Effective top tube height is about 48 cm, meaning for a 48 cm c-c frame (*edit I think that might be an exaggeration in that the frame is smaller... c-c is 40 cm, c-t is probably 44-46 cm). This means the top tube starts out forward and low, at least compared to, say, a 60 cm frame, because the vertical start point of the rear of the top tube is closer to the BB center. On a taller frame it would be pushed back a bit due to the much longer seat tube sloping away from the BB center, and usually at a slacker angle than 75.5.
__________________
"...during the Lance years, being fit became the No. 1 thing. Totally the only thing. It’s a big part of what we do, but fitness is not the only thing. There’s skills, there’s tactics … there’s all kinds of stuff..." Tim Johnson
"...during the Lance years, being fit became the No. 1 thing. Totally the only thing. It’s a big part of what we do, but fitness is not the only thing. There’s skills, there’s tactics … there’s all kinds of stuff..." Tim Johnson
#4633
I stripped another dang pinch bolt on my stages crank arm with my torque wrench. Does anyone know if titanium bolts are less soft? Would it somehow throw off my power numbers if I'm using them with a stages? I've gone through like 6 of these now and they're all soft as heck.
#4635
I do think a high BB affects tip in, making it harder to tip in. For a few years Cannondale offered certain mountain bikes in two radically different BB height configurations, I want to say 10" and 12" high, the latter to make riding logs/etc easier (late 80s so no suspension yet). I had a 12" high one or whatever was taller. I could tell immediately when I was on a taller BB version or a shorter one. The difference was pronounced/exaggerated for sure, but I wasn't keen on the tall BB.
One thread this discussion went down on Facebook was the idea that the differences in BB drop are small, therefore how could it really matter that much? I don't know, of course. But I do know that 3 mm difference in my saddle height is the difference in being able to ride thousands of miles with no problem or developing a knee problem within a few days. Seemingly small differences can be really important.
I am now talking myself out of the idea that descending gravel roads at high speed on the Ridley would be fine. Maybe I can get used to it, but it really is tricky to get it to lean, and the Ritchey is easier. My main concern is traction. I probably just need bigger tires.
What the means for a high BB crit bike, though, I'm not sure. Flat cornering in a crit vs descending a mountain aren't 100% the same.
#4636
I stripped another dang pinch bolt on my stages crank arm with my torque wrench. Does anyone know if titanium bolts are less soft? Would it somehow throw off my power numbers if I'm using them with a stages? I've gone through like 6 of these now and they're all soft as heck.
#4638
Senior Member

Joined: Jan 2014
Posts: 10,588
Likes: 427
From: Southern California, USA
Bikes: 1979 Raleigh Team 753
I'm getting confused by the double negatives.
Ti is softer than stainless steel. And I think we are asking about stiffness/hardness, not strength.
modulus of elasticity relative values
ti alloy ~ 120
SS ~190
Carbon Fibre ~ 180
Ti is softer than stainless steel. And I think we are asking about stiffness/hardness, not strength.
modulus of elasticity relative values
ti alloy ~ 120
SS ~190
Carbon Fibre ~ 180
#4639
Anybody have experience with 1.25" and 2" hitch racks?
My wife's current car has a 1.25" hitch, and we have a Yakima Hold Up 2 rack. But, after a little over 7 years, it's showing its age. So, we should probably consider getting her a new rack.
The new car we are getting her can do a 1.25" or 2" tow hitch. I'm wondering if a 2" hitch is measurable more secure for the rack or does it not matter much.
My wife's current car has a 1.25" hitch, and we have a Yakima Hold Up 2 rack. But, after a little over 7 years, it's showing its age. So, we should probably consider getting her a new rack.
The new car we are getting her can do a 1.25" or 2" tow hitch. I'm wondering if a 2" hitch is measurable more secure for the rack or does it not matter much.
#4640
¯\_(ツ)_/¯
Joined: Jun 2008
Posts: 10,978
Likes: 4
From: Redwood City, CA
Bikes: aggressive agreement is what I ride.
Anybody have experience with 1.25" and 2" hitch racks?
My wife's current car has a 1.25" hitch, and we have a Yakima Hold Up 2 rack. But, after a little over 7 years, it's showing its age. So, we should probably consider getting her a new rack.
The new car we are getting her can do a 1.25" or 2" tow hitch. I'm wondering if a 2" hitch is measurable more secure for the rack or does it not matter much.
My wife's current car has a 1.25" hitch, and we have a Yakima Hold Up 2 rack. But, after a little over 7 years, it's showing its age. So, we should probably consider getting her a new rack.
The new car we are getting her can do a 1.25" or 2" tow hitch. I'm wondering if a 2" hitch is measurable more secure for the rack or does it not matter much.
#4641
Yes, I was saying Ti bolts are easier to strip than standard stainless steel, not harder.
#4643
Senior Member
Joined: Aug 2012
Posts: 606
Likes: 0
From: Houston
Bikes: Trek Madone, Blue Triad SL, Dixie Flyer BTB
You can carry two bikes on a 1.25" 1up hitch, you buy the single bike version with the 1-bike add-on. Works great on my wife's vehicle which had dealer-installed 1.25" hitch. Class 1 hitch is plenty strong enough for carrying a couple bikes. I actually like this better than the 2-bike rack because it's less bulky when only carrying one bike.
#4644
Ninny
Joined: Jan 2010
Posts: 5,295
Likes: 1
From: The Gunks
You can carry two bikes on a 1.25" 1up hitch, you buy the single bike version with the 1-bike add-on. Works great on my wife's vehicle which had dealer-installed 1.25" hitch. Class 1 hitch is plenty strong enough for carrying a couple bikes. I actually like this better than the 2-bike rack because it's less bulky when only carrying one bike.
#4645
Senior Member
Joined: Aug 2012
Posts: 606
Likes: 0
From: Houston
Bikes: Trek Madone, Blue Triad SL, Dixie Flyer BTB
#4646
my bike is 'ticking'. this kind of **** drives me insane.
i sold my spare bike on friday and the very next day it started on my main bike when i was riding with ygduf. at first we thought it might be the seatpost, but by the end of the ride it was making noise out of the saddle as well. i took off the seatpost anyway and cleaned it, but no luck. it seems to 'tick' every pedal stroke when the left pedal is at the bottom of the stroke (or right is at the top, i guess). i've checked/tightened my cleats, checked to see if the crank was hitting the front derailleur, checked the headset (it still ticks if im riding without hands) and QRs. it doesnt seem to be power or cadence related (though high torque situations make it louder usually, but high power fast cadence sprinting down a hill and it made no noise at all).
really hoping its like a bearing in the BB or something, i really really really dont want it to be related to the pedals because i have vectors and removing them is out of the question unless im absolutely positive it cant be anything else. i spent a day painstaking calibrating them 1.5 years ago and havent had to touch them since, but i'll probably buy a new power meter (SRM or DZero) before dealing with that again.
i sold my spare bike on friday and the very next day it started on my main bike when i was riding with ygduf. at first we thought it might be the seatpost, but by the end of the ride it was making noise out of the saddle as well. i took off the seatpost anyway and cleaned it, but no luck. it seems to 'tick' every pedal stroke when the left pedal is at the bottom of the stroke (or right is at the top, i guess). i've checked/tightened my cleats, checked to see if the crank was hitting the front derailleur, checked the headset (it still ticks if im riding without hands) and QRs. it doesnt seem to be power or cadence related (though high torque situations make it louder usually, but high power fast cadence sprinting down a hill and it made no noise at all).
really hoping its like a bearing in the BB or something, i really really really dont want it to be related to the pedals because i have vectors and removing them is out of the question unless im absolutely positive it cant be anything else. i spent a day painstaking calibrating them 1.5 years ago and havent had to touch them since, but i'll probably buy a new power meter (SRM or DZero) before dealing with that again.
#4647
Senior Member
Joined: Apr 2015
Posts: 4,272
Likes: 1,304
From: Seattle
Does the bike make the noise if you ride it with the seatpost removed? Sometimes they tick against the seat tube under power. I've seen that happen with an old steel bike before, anyway.
#4648
my bike is 'ticking'. this kind of **** drives me insane.
i sold my spare bike on friday and the very next day it started on my main bike when i was riding with ygduf. at first we thought it might be the seatpost, but by the end of the ride it was making noise out of the saddle as well. i took off the seatpost anyway and cleaned it, but no luck. it seems to 'tick' every pedal stroke when the left pedal is at the bottom of the stroke (or right is at the top, i guess). i've checked/tightened my cleats, checked to see if the crank was hitting the front derailleur, checked the headset (it still ticks if im riding without hands) and QRs. it doesnt seem to be power or cadence related (though high torque situations make it louder usually, but high power fast cadence sprinting down a hill and it made no noise at all).
really hoping its like a bearing in the BB or something, i really really really dont want it to be related to the pedals because i have vectors and removing them is out of the question unless im absolutely positive it cant be anything else. i spent a day painstaking calibrating them 1.5 years ago and havent had to touch them since, but i'll probably buy a new power meter (SRM or DZero) before dealing with that again.
i sold my spare bike on friday and the very next day it started on my main bike when i was riding with ygduf. at first we thought it might be the seatpost, but by the end of the ride it was making noise out of the saddle as well. i took off the seatpost anyway and cleaned it, but no luck. it seems to 'tick' every pedal stroke when the left pedal is at the bottom of the stroke (or right is at the top, i guess). i've checked/tightened my cleats, checked to see if the crank was hitting the front derailleur, checked the headset (it still ticks if im riding without hands) and QRs. it doesnt seem to be power or cadence related (though high torque situations make it louder usually, but high power fast cadence sprinting down a hill and it made no noise at all).
really hoping its like a bearing in the BB or something, i really really really dont want it to be related to the pedals because i have vectors and removing them is out of the question unless im absolutely positive it cant be anything else. i spent a day painstaking calibrating them 1.5 years ago and havent had to touch them since, but i'll probably buy a new power meter (SRM or DZero) before dealing with that again.
#4649
just went and tried without the seatpost (it was actually really difficult to ride without the seat! felt so unbalanced and almost died unclipping) - still ticks without the seatpost. i guess that rules it out.
just tried switching out both front and rear skewers with another brand - no luck
just tried switching out both front and rear skewers with another brand - no luck
Last edited by scheibo; 03-13-17 at 08:40 PM. Reason: included followup results




