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Discussion Starter · #1 ·
While saving up for a frame that truly fits my size, I'd like to make some adjustments to my 55 cm frame to better fit my body type.

I'm 5 ft 10.5 inches tall and my inseam is 33.625. From the proportions I've learned, my ideal frame size should be 57cm.

I have a 55 cm Trek 2100 composite frame. I've adjusted the seat height and the seat forward/backward measurements using a plum line (from foward knee to pedal) as my gauge. So my saddle is now correctly adjusted, I hope. The issue now is that since my seat has been raised, my bars are sitting a bit too low and too close to my core.

Is there a way to lift a 1" threadless headset and extend the stem to better fit my body type on my seemingly too-small-for-my-size frame? From what I've read thus far, it seems that most of these options are better found for a 1-1/8" headset...

Thanks for any thoughts/direction...
 

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info...

Setting the knee over the pedal is not necessarily "correct", particularly if you had the saddle further back and it was working. A lot of experts think that KOP means nothing at all and it's more important for the rider to be balanced over the saddle to reduce the amount of weight on the hands.

You don't say how much you raised your saddle or how much drop there is from the saddle to the top of the bars.

As for raising the handlebar height, the easiest way might be the purchase of a new stem with a different angle and length.

FWIW, if you're properly balanced over the saddle it makes a large drop from the saddle to the bars easier to tolerate. I'd consider moving it back, if the amount is not too large.

Another comment about "frame size". These days, numbers like a 55 or 57cm really don't mean much. What you really need to look at the the head tube length, with the headset, whihc determines the vertial size of the frame and the reach. Reach is affected by the TT length and the seat tube angle.
 

· monkey with flamethrower
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The internet can't fit your bike for you. You should go to a reputable local shop with your bike to talk about such issues.
There are lots of variables in fitting a bike and frankly with bicycles the inseam isn't that important of a measurement with most modern bikes. Your torso length plays a far bigger factor in bicycle fit that your inseam. Other variables are important such as arm length, foot size and your level of fitness and flexibility.
You could very well have the right size bicycle and just need a few tweaks here and there, possibly a different size stem. And another thing, a good deal of folks don't know how to sit properly on a bicycle, being shown how to do so will greatly improve the overall fit of the bike. Whomever is fitting should talk to you about such things.
And as C-40 said, the 50 some odd centimeter measurement doesn't really matter.
 

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I agree with the above post. But quickly I would say that with an inseam of 33.5 your ideal frame is actually around 55cm. I would also suggest that your saddle to crank height should be around 29.7 inches.

Now depending on how long, or short you torso is would depend on the rest of your set up.

You would also do best with a 172.5 cranks. But that's just my opinion.
 

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Discussion Starter · #5 ·
more details...

Thanks for the feedback.

Here's some more details of what I've gauged in terms of measurements.

I used my inseam as directed by several bike sites to determine saddle height. Formula:
0.883 X 85.4 cm (inseam length) = 75.4 cm. So I raised my the saddle 75.4 cm (measured from center of bottom bracket to top of saddle).

The drop from the top of the seat to the top of the handlebars is about 5 inches.

How will I know if I'm "properly balanced" over the saddle?
 

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As far as the oroginal OP's question about rasing the bars on his current bike, you can get a adapter to use a threadless stem with a threaded fork, and then use a stem with a higher rise, such as a 17 degree stem to achive a higher handlebar position. The adapters should be available from Nashbar online if you can't find one locally.
 

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disagree...

I don't agree with the idea that torso length is far more important than inseam or saddle height. It's quite common for frames sizes to have 2cm jumps, while the TT length or reach may change by 1cm or even less. In an attempt to get the perfect frame reach, the vertical size of the bike can be totally wrong. Both should be considered. If you have a long torso, expect to use a 120-130mm stem and perhaps long reach bars. Short torso riders should look into short reach bars to start with, then select the proper stem length.
 

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advice..

The saddle height recommendation is OK, but there is always the need for fine tuning due to difference in pedal and shoe stack heights and a the riders preferred foot angle while pedaling. Consider it a starting point and adjust as necessary. Ideally, you'll end up with a smooth pedal stroke and not pushing down hard at the very bottom of the stroke, where torque cannot be delivered.

As for the saddle balance, read this article for some ideas. I don't agree with all the ideas, but being balanced is more important than KOP, IMO. There's a range where the saddle is back far enough to unweight the hands, but moving the saddle further back is of no value. It's pretty much an experimental procedure.

http://www.peterwhitecycles.com/fitting.htm

As for your saddle to bar drop, 5 inches is too much for most people. 3-4 is a lot more common. Depending on your current stem angle, all you might need is an angle change, but high rise stem will be at least one size shorter, horizontally, than the advertised length.
 
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