Tandem Tom

So in a prior post I mentioned how my mind wanders while we are are a bike tour. Well after coming back from a 1800 mile tour we both get zapped with a really crummy cold and laryngitis! So not much to do except read an ruminate!
MY current ques is about top tube angle. Currently my LHT has a level TT. So I was wondering how much of a slope/angle could one have? This would be for reduced step over.And what if any would this affect the bike handling?
Thanks!
Now back to my stack of Kleenex!

guy153

I think there's a good case for a sloping TT on a touring bike because you want a high stack. Surly extend the HT above the TT junction just to contrive a horizontal TT but this is putting aesthetics above engineering. Which is fine I guess. I mean we all do that.
The other end of it is to have more seatpost stickout for standover as you say. More seatpost is also supposed to give you kind of suspension and make the bike more comfortable. Also desirable on a tourer.

I used a 4° TT on my Euro style trekking/touring bike and I reckon it looks nice. Only slightly sloping. Aesthetically I don't like the look of excessive seatpost stickout even if it is supposed to add comfort.

Steve B.

Many manufacturers state that the sloping too tube stiffens the main triangle. That wouldn't be a bad thing on a touring bike as you dont want a squirmy bike. But there are many more design choices that can make a tourer have the correct stiffness and handling, it really just becomes an aesthetic choice,

Andrew R Stewart 

Excepting fitting needs that are way off the bell curve (and a small woman of grand age might just sit at the fringes of normality) TT slope is a non issue as long as certain specs are respected. Stand over height, post extension, bar/stem height, are some obvious ones. But stay length and seat stay angle WRT foot length and type of rear brake is an aspect usually found out after the bike is assembled and being delivered I've seen heel contact with some cantis as example and why it's rare to see cantis on mixte bikes. Another aspect of TT slope is how long the ST becomes and if that will fit a bottle or pump. Andy

Tandem Tom

Thanks for your replies!
Andy,the water bottle space was an issue that I had a fleeting thought about.
I might take my existing LHT and use some wood strips at different angles to get some ideas.

TiHabanero

The first frame I built has a top tube drop of 1cm from the head tube to the seat tube. I did it to get an extra length in the head tube and keep a certain amount of seat post exposed. On a touring frame I dropped the BB 1.5cm to get extra stand over clearance and have less seat post exposed than the first bike. Simply for the look I wanted.
Yes, a sloped TT works just fine and can serve a purpose if desired.