Frame Size and Center of Gravity
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Frame Size and Center of Gravity
So I had a fright this weekend when I took my new road bike out for its first long ride on a winding, hilly bike path. Up until now I have only been using it for commuting on urban roads.
Going down the big hills, I was pretty shaken at how little control I felt over my bike. Same with making sharp turns. I felt like I was constantly about to topple over when I banked hard. I was riding fairly timidly compared to my old road bike, a Univega touring bike that was noticeably heavier and smaller (~6cm height difference). I bought this bike for a great deal on Craigslist; during a test ride I didn't feel too unstable, so I didn't think the extra 2cm was an issue.
I'm 5'9" with a 31" inseam, so most size guides say I should be at a 53-54cm frame. My Fuji is a 56. The bike is so different than my 50cm Univega in style, weight and height that I can't tell if the frame size is what's causing me to feel so unstable. Any input? I am considering whether I should sell this one and get a new bike, or just keep riding until I get used to it. I've test ridden a lot of different bikes, but I can't do that in the conditions that are at issue.
Going down the big hills, I was pretty shaken at how little control I felt over my bike. Same with making sharp turns. I felt like I was constantly about to topple over when I banked hard. I was riding fairly timidly compared to my old road bike, a Univega touring bike that was noticeably heavier and smaller (~6cm height difference). I bought this bike for a great deal on Craigslist; during a test ride I didn't feel too unstable, so I didn't think the extra 2cm was an issue.
I'm 5'9" with a 31" inseam, so most size guides say I should be at a 53-54cm frame. My Fuji is a 56. The bike is so different than my 50cm Univega in style, weight and height that I can't tell if the frame size is what's causing me to feel so unstable. Any input? I am considering whether I should sell this one and get a new bike, or just keep riding until I get used to it. I've test ridden a lot of different bikes, but I can't do that in the conditions that are at issue.
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Did the Univega have 32mm tires? When I switch between my Voyageur and my Domane, there is a huge difference in handling and 'nervousness'. My Voyageur has 32mm tires while my Domane has 25mm; I have found this to make a pretty big difference in handling. Also, if the new bike has a much shorter wheelbase or sharper head tube angle, your handling will seem 'twitchier' until you get used to it.
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Remember, 2 cm means a lot to some people....When I went from a 58 to a 56, I had to get use to how the bike handles...which mean I am one of those people
But in all seriousness, is your reach too far? May want to consider a shorter stem. I got a longer stem (new take off, cannondale c3) fora whooping 10$, 15 after shipping. Check ebay.
Give it a few easy rides (I would say 5 or 6 more) and avoid any steep hills/sharp turns. If you still feel uneasy you may want to get a fit (if you don't know how to fit your self [which isnt a bad thing]) or sell it for a smaller frame.
And for reference my inseam is 35/36ish for my 56cm caad10 and I do show a good amount of seat post.
But in all seriousness, is your reach too far? May want to consider a shorter stem. I got a longer stem (new take off, cannondale c3) fora whooping 10$, 15 after shipping. Check ebay.
Give it a few easy rides (I would say 5 or 6 more) and avoid any steep hills/sharp turns. If you still feel uneasy you may want to get a fit (if you don't know how to fit your self [which isnt a bad thing]) or sell it for a smaller frame.
And for reference my inseam is 35/36ish for my 56cm caad10 and I do show a good amount of seat post.
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Did the Univega have 32mm tires? When I switch between my Voyageur and my Domane, there is a huge difference in handling and 'nervousness'. My Voyageur has 32mm tires while my Domane has 25mm; I have found this to make a pretty big difference in handling. Also, if the new bike has a much shorter wheelbase or sharper head tube angle, your handling will seem 'twitchier' until you get used to it.
On my Univega I leaned forward more
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#7
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It's probably not the frame size. It's the frame geometries.
The touring bike will have a long wheelbase, and the front fork will be designed for stability. Your new road bike is probably designed to be twitchier, which makes it feel faster, but also makes it harder to control in situations like a descent.
You'll probably get used to it in a few rides. Probably.
The touring bike will have a long wheelbase, and the front fork will be designed for stability. Your new road bike is probably designed to be twitchier, which makes it feel faster, but also makes it harder to control in situations like a descent.
You'll probably get used to it in a few rides. Probably.
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It does look a little bigger than it needs to be, but not so big you can't get used to it and make it work. The design has a very tall head tube, so your bar height is up there.
I'd try two things: sliding your seat forward a bit, and flipping your stem so that it angles downward.
I'd try two things: sliding your seat forward a bit, and flipping your stem so that it angles downward.
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Also if you're pushing onto the bars (would happen all the time on my 58 around mile 15ish) you could be trying to control the bike.
More muscles tensed up means less wiggle room for the bike. And less wiggle room means a greater sense of control.
Then when you need to reposition yourself for a downhill segment or a sharp turn, you get thrown all out of wack and feel like the bike is uncontrollable because you dont have the tensed up sense of security.
Also, if your upper traps are getting sore, if may be because your bars are too high or the bike is just too big for you.
And just something to think about, if you decide to lower the bars you have to think about resale. You can slam the stem and fit it to you, but later on if you decide to sell the bike for a different frame size not everyone will want a slammed bike meaning you have greatly reduced the number of potential buyers and you may be stuck with the bike for a while.
But tweak the adjustable parts first and see what happens
More muscles tensed up means less wiggle room for the bike. And less wiggle room means a greater sense of control.
Then when you need to reposition yourself for a downhill segment or a sharp turn, you get thrown all out of wack and feel like the bike is uncontrollable because you dont have the tensed up sense of security.
Also, if your upper traps are getting sore, if may be because your bars are too high or the bike is just too big for you.
And just something to think about, if you decide to lower the bars you have to think about resale. You can slam the stem and fit it to you, but later on if you decide to sell the bike for a different frame size not everyone will want a slammed bike meaning you have greatly reduced the number of potential buyers and you may be stuck with the bike for a while.
But tweak the adjustable parts first and see what happens
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It sounds like your fit is not quite right. This is a great website to give you some ideas on how to set your bike up without getting a pro fit, which I would highly recommend. Welcome » Steve Hogg's Bike Fitting Website
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Yep - check your fit. Putting too much weight on your hands indicates something may need to be tweaked. In my past experience, hurting hands were because I was putting too much weight on them; my hands were too far in, not letting my arms/elbows get out in front of me. Your situation may easily be remedied by stem angle/length adjustments.
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It's hard to tell from the one picture, but given that your right heel is UP and your right leg's bend is about what I'd expect to see at the bottom of the pedal stroke, I think you might need to lower the seat a little. And yeah, as it seems that it's already pretty low, maybe the bike is a little big for you.
That being said, descending is definitely a skill. You don't just hold on and go wheeeee! (well, maybe a little...)
There are a lot of things you can do to make things more stable/controllable.
First thing, don't tense up. Your hands shouldn't have a death grip on the bars. I like to be in the drops and keep two fingers on each brake, ready. Make sure the other two fingers (on the bar) aren't directly behind the lever.
Next, when hitting a turn at high-ish speed. put the foot on the outside of the turn DOWN. So if you're turning left, put the right foot down and put your weight on it. This helps to keep the tires planted on the ground, carving a line around the curve.
Some will argue for one brake or the other, but I tend to use both brakes during descents. Don't just mash them down and skid down on your brakes -- that'll create heat on your rims and could blow your tires. You have to feel out where your center is (front to back) and feather each brake accordingly to keep it there while keeping your speed where you need/want it. You definitely don't want to be out over your front wheel. I tend to try to get my chin right over my stem by a couple inches (not too close or you'll lose some teeth when you hit that unexpected bump. Since, however, you have a nice loose grip, the bump won't buck you off the bike/out of control, it'll just bounce under you and settle back in, like a mountain bike.)
It helps to be out of the saddle and have your legs acting as shocks, of sorts.
Yes, your neck, hands and legs may begin to ache. Again, descending isn't just a slide. Done right, it's nearly as tough as the climb -- just in a different way.
If you really want to trip out, look of 'death wobble'. Then be sure that while descending on straights, touch the top tube with your knee(s) frequently (or constantly) and also pedal a bit here and there (even though you're spun out beyond the top gear.) These sorts of things can help avoid the bike reaching a resonance and vibrating wildly and killing you.
Oh yeah, and I am no expert, I just live near a lot of hills and find myself descending a lot in some scary spots, so I've read a lot on this forum and watched some quality youtube videos on the subject where actual expert riders throw out gems like these. I highly recommend you seek out some of the same info.
Be safe out there! (that being said, I thoroughly enjoyed blowing away the whole club ride a few weeks ago on a big local descent and hitting 49.5 mph in the process. Talk about adrenaline!)
That being said, descending is definitely a skill. You don't just hold on and go wheeeee! (well, maybe a little...)
There are a lot of things you can do to make things more stable/controllable.
First thing, don't tense up. Your hands shouldn't have a death grip on the bars. I like to be in the drops and keep two fingers on each brake, ready. Make sure the other two fingers (on the bar) aren't directly behind the lever.
Next, when hitting a turn at high-ish speed. put the foot on the outside of the turn DOWN. So if you're turning left, put the right foot down and put your weight on it. This helps to keep the tires planted on the ground, carving a line around the curve.
Some will argue for one brake or the other, but I tend to use both brakes during descents. Don't just mash them down and skid down on your brakes -- that'll create heat on your rims and could blow your tires. You have to feel out where your center is (front to back) and feather each brake accordingly to keep it there while keeping your speed where you need/want it. You definitely don't want to be out over your front wheel. I tend to try to get my chin right over my stem by a couple inches (not too close or you'll lose some teeth when you hit that unexpected bump. Since, however, you have a nice loose grip, the bump won't buck you off the bike/out of control, it'll just bounce under you and settle back in, like a mountain bike.)
It helps to be out of the saddle and have your legs acting as shocks, of sorts.
Yes, your neck, hands and legs may begin to ache. Again, descending isn't just a slide. Done right, it's nearly as tough as the climb -- just in a different way.
If you really want to trip out, look of 'death wobble'. Then be sure that while descending on straights, touch the top tube with your knee(s) frequently (or constantly) and also pedal a bit here and there (even though you're spun out beyond the top gear.) These sorts of things can help avoid the bike reaching a resonance and vibrating wildly and killing you.
Oh yeah, and I am no expert, I just live near a lot of hills and find myself descending a lot in some scary spots, so I've read a lot on this forum and watched some quality youtube videos on the subject where actual expert riders throw out gems like these. I highly recommend you seek out some of the same info.
Be safe out there! (that being said, I thoroughly enjoyed blowing away the whole club ride a few weeks ago on a big local descent and hitting 49.5 mph in the process. Talk about adrenaline!)
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I think this may be what my problem is. The Univega is 27” x 1 ¼” whereas the Fuji is 25mm, and it is noticeably twitchier. That combined with the switch from steel to aluminum makes the ride a lot bumpier too.
I don’t feel like it’s too far, but it may be too high. When I’m in the drops for a while, my hands start to ache from the weight I push onto them. Part of that may be the WSD making the drops more shallow than I’m used to.
On my Univega I leaned forward more
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First thing, don't tense up. Your hands shouldn't have a death grip on the bars. I like to be in the drops and keep two fingers on each brake, ready. Make sure the other two fingers (on the bar) aren't directly behind the lever.
Next, when hitting a turn at high-ish speed. put the foot on the outside of the turn DOWN. So if you're turning left, put the right foot down and put your weight on it. This helps to keep the tires planted on the ground, carving a line around the curve.
If you really want to trip out, look of 'death wobble'. Then be sure that while descending on straights, touch the top tube with your knee(s) frequently (or constantly) and also pedal a bit here and there (even though you're spun out beyond the top gear.) These sorts of things can help avoid the bike reaching a resonance and vibrating wildly and killing you.
Next, when hitting a turn at high-ish speed. put the foot on the outside of the turn DOWN. So if you're turning left, put the right foot down and put your weight on it. This helps to keep the tires planted on the ground, carving a line around the curve.
If you really want to trip out, look of 'death wobble'. Then be sure that while descending on straights, touch the top tube with your knee(s) frequently (or constantly) and also pedal a bit here and there (even though you're spun out beyond the top gear.) These sorts of things can help avoid the bike reaching a resonance and vibrating wildly and killing you.
Question – about touching the top tube with knees, should it be both at the same time or alternating depending on which is higher? I have a tendency to favor putting weight in my right foot to feel stable, so my knees are almost never level when I’m coasting. I’m wondering if this is contributing to my feeling of instability, as I do the same thing during turns—my right foot is always between 5-7 o’clock. I never really thought of it as an issue, although that probably explains why I always fall to the right when I crash.
The tire size will make a difference - not because of the width but because of the weight. The tires on the Fuji are probably significantly lighter. The reduction in rotating mass reduces the gyroscopic effect of the spinning wheels, allowing the bike more freedom to make side-to-side movements.
I’ll try moving my saddle back, seat post down, and removing some of the spacers from my stem. I was told by my LBS that the leg should extend about 90% at 6’oclock, but again that was for a much smaller bike so I could still reach the ground with no strain. As it is, I have to keep my foot flexed with heel ~4in from the ground to stay perpendicular. Makes it interesting at intersections when I inch forward in cleats to get a better position
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Only adjust one thing at a time, so that you can identify what is going on.
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I was looking at the pic again, and yeah, that bike is too big. Probably not unworkable, but if you have the option to change it for a smaller one, it'd be worth considering.
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I see numerous posts suggesting moving the saddle. Don't do this! Adjust the saddle to fit the pedals only. If you need to adjust the reach change the stem.
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I have a tendency to favor putting weight in my right foot to feel stable, so my knees are almost never level when I’m coasting. I’m wondering if this is contributing to my feeling of instability, as I do the same thing during turns—my right foot is always between 5-7 o’clock. I never really thought of it as an issue, although that probably explains why I always fall to the right when I crash.
Are the lighter weight tires what cause the death wobble @goenrdoug mentioned? I’ve noticed that lateral wind affects the direction of my front wheel significantly more than my Univega, although I’ve never lost that much control.
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As for the high foot/low foot thing, it matters a lot. As @Kopsis mentioned, the low foot on the outside of the curve is supposed to plat you so you can carve the turn.
Check this extreme example out:
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To be fair, I felt the same loss of control and nervousness when I switched from a comfort hybrid to the Univega a few years ago. I’m slowly making my way up the bike ladder
I think this may be what my problem is. The Univega is 27” x 1 ¼” whereas the Fuji is 25mm, and it is noticeably twitchier. That combined with the switch from steel to aluminum makes the ride a lot bumpier too.
I don’t feel like it’s too far, but it may be too high. When I’m in the drops for a while, my hands start to ache from the weight I push onto them. Part of that may be the WSD making the drops more shallow than I’m used to.
On my Univega I leaned forward more
I think this may be what my problem is. The Univega is 27” x 1 ¼” whereas the Fuji is 25mm, and it is noticeably twitchier. That combined with the switch from steel to aluminum makes the ride a lot bumpier too.
I don’t feel like it’s too far, but it may be too high. When I’m in the drops for a while, my hands start to ache from the weight I push onto them. Part of that may be the WSD making the drops more shallow than I’m used to.
On my Univega I leaned forward more
Looks like the frame is big for you, notice the saddle is almost no travel from the top bar. if the frame size is big, you need to make a decision to replace it with the right one.