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Discussion Starter · #1 ·
I am thinking that my frame is too small

It does fine climbing and flats, but if I am really hammering a descent when I pull up on the pedal stroke and I am not paying full attention to form I inadvertently lift the rear wheel off the ground. Sometimes it gets scary. Now I do not race often so this isn't a serious problem but I do like to go fast.

I often shift my weight to the rear of the seat when descending to get a good balance point for cornering.

Is that a sign of a bike that is too small? I have a ton of saddle to bar drop which is not uncomfortable but may not be needed on a frame that fits.

Any help in determining if it is too small would be a huge help because I could likely still sell this frame for as much as I have in it.

Then the next question: what should I get?
 

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Adorable Furry Hombre
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ukwill said:
never heard of the rear wheel being lifted off the ground...
whats your height and the bikes horizontal TT c-c?
And also I would ask how much saddle-to-bar drop the OP has...
 

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If your rear wheel doesn't touch the ground, you should get a bigger wheel. That should solve the problem.
 

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The frame could be too small...but it's more likely your weight is just not balanced in that situation. When you accelerate hard in the same situation, just move your weight back a little and it will likely solve the problem.

I ride a small frame but don't have this issue...on my TT bike though when I'm accelerating out of the starting gate my rear wheel skips because my weight is far forward on the bike and I'm accelerating very hard.
 

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if you're moving your mass forward and pulling up on your pedal, it's not uncommon for the back wheel to pop off the ground. Sometimes a symptom of a gear that's too high.
 

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It could be all sorts of things. Frame could be too small. Saddle to bar drop could be too much, causing a significant weight imbalance between the front and rear wheels. Chainstays could be too short. Pedal stroke could be poor. That shifting of weight to the rear on descents is likely not the cause of the problem but it certainly can result in poor handling on descents.

Start by giving us your inseam, overall height, weight, and show us a picture of the bike.
 

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Discussion Starter · #10 ·
pants inseam- 33-34"
weight 173
height 6'2-1/2"

note this is an early photo the stem is flipped up, raising the bars a little from what is shown:

 

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vexatious enigma
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tjib13 said:
pants inseam- 33-34"
weight 173
height 6'2-1/2"

note this is an early photo the stem is flipped up, raising the bars a little from what is shown:

From this it looks like your really bent over and cramped on the bike.
 

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tjib13 said:
...note this is an early photo the stem is flipped up, raising the bars a little from what is shown:...
That is your problem right there.....

Blue bikes = trouble.

The quick fix is to spray paint it red.

Or just get a bigger rear wheel.
 

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So you're riding a 573mm TT, which isnt really small for 6'2''.. though Im 6ft and ridea a 582mm TT and a 120/130mm stem..
 

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get a bathroom scale and figure out your weight distribution, should be close / around 55-60% rear.
 

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I see three other problems.

1) The tilt of you saddle causes your front wheel to try to drive itself into the ground, causing your rear wheel to lift up.

2) You need a bigger and heavier seat bag to counteract this tendency.

3) Science has proven that Ciussi waterbottle cages can amplify this tendency.
 

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You're right.

The frame is too small. Saddle way up and pointed down. Not good. I'd bet there's more than 40% weight on front wheel, for sure. Accentuated while descending. Can you move the saddle all the way back on the rails and make it level? That would rotate some more weight towards the rear wheel, giving more traction and maybe solving the slippage problem. Check the fit programs online, but I'd say a 60 cm. frame would be more comfortable, achieving a better for-aft balance.
 

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Fedrico and I think alike-frame is too small and the bars are too low, even if you say you've flipped the stem up. There's not enough weight over the rear wheel, as a result. A longer top tube would make more sense for your height. That would lengthen the wheelbase and place more weight between the wheels or behind the front wheel, depending on how you look at it. The slope of the saddle is an indicator to me that either the seat's too high or the bars are too low.
 
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