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Discussion Starter #1
I am currently using a 110mm -17 stem on my Bianchi San Lorenzo with 20mm spacers on it.There is a 115mm drop from the saddle to the top of the handlebar.

I am getting ready to build a Freccia Celeste and I was wondering if there was anything on the net that showed how different angle stems changed the handlebar height.For instance,I know to get the same drop from the saddle to Handle bar on the San Lorenzo with a -10/80 degree stem I would have to remove some spacers but how much?The new bike has a 72.5 degree head tube Vs the San Lorenzos 73 so to get the same drop with a -10 seems like the stem would have a lot less spacers under it.(head tubes are same length).

Seems like there has to be some formula or chart fo this for the various stem lengths and angles?I have looked and came up with nothing.One reasons ask is that there are a lot more options for stems with a -10 andle vs -17.
 

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simple trig..

The vertical rise of a stem is the sine of the angle relative to the ground times the length.

A -17 stem is rearely seen these days, since it has no rise.

An -10/80 degree stem will have a rise of sin(80-73) x 110 = 13.4mm. This assumes a 73 degree head tube angle.

An 84 degree would be sin11x 110 = 21mm.

Another thing that affects the amount of spacers required is the steering tube clamp height. The most common these days is a 40mm height, but some, like the ITM Milennium are only 35mm and a few are more than 40mm.
 

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Discussion Starter #4
Simple trig?Is there such a thing? :D

Thanks for the info guys.That habcycles link seems to explain it all.
 
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