General bike geometry quest

[Scvintage]

The more I dig into the subject of bike geometry the more it looks like people arguing over what hair color they prefer in a girlfriend or the attributes of a good wife...

Is there a good old fashion chiseled in stone reference based on facts? What I’m attempting to figure out is taking an old cannondale super v700 and adjusting a few parts to mimic a modern geometry. The reference point I’d like to start with is wide modern handlebars... changing items if needed to make it perform normal (short stem, move the seat, adjust crank length or whatever)

Pointing a finger in a general reference direction is what I’m looking for.

 

[My_Teenage_Self]

I guess you're talking more about bike fit than geometry...? You can't really adjust geometry, you can increase/decrease bottom bracket height, ST and head angle, but you can't adjust them independently.

Modern bikes are longer, lower and slacker, but that's more about wheelbase, BB height and head angle. Seat tube angles tend to have gotten steeper. there is a trend to top tube reach to have increased, but in my experience it's actually getting back to longer 90s bikes were anyway (with stem length taken into account).

Now with all that said, you've chosen one of few frames that might accept modernisation better than most. With it's big headtube, you can actually get a headset that will slacken your headangle by a few degrees. with a longer travel fork, you'll be getting somewhere.

With all THAT said, I've run short stems and wide bars since the mid 90s. I've always liked it. so long as your frame is long enough to account for the short stem (and wide bars account for some of that) then you'll have no problems.

 

[Scvintage]

Re:

I guess you could look at it as making a scale model of modern geometry. Take two cad models of old & new... shrink modern to fit in wheelbase of old. Next look at “nodes” of scaled modern and see if old can be adjusted to match. Theoretically speaking

 

[Scvintage]

Re:

https://www.workscomponents.co.uk/#

Anyone familiar with this company? Do these headsets “tilt” the fork tube by the degrees mentioned in their product descriptions?

 

[mattr]

Yes. Add (or remove) degrees to your head angle.

 

[mattr]

And if you mean modern XC geo. It's pretty much impossible to duplicate on an old frame.
Unless you get something that's too big for you, to get the length once you've "corrected" the seat angle without needing a 15cm stem (which stuffs up the handling), negative rise stem to get the bars back at the right height on the *much* larger frame and an angle set to kick the head angle out.
And the Super V frames are, from what I can remember, very old school. Tall, short and steep.

I've tried it on a less old school frame and failed.

 

[Scvintage]

Re:

I was debating making a hardwood inset on a lathe to goof with fork angle

 

[mattr]

Make sure the head tube has sufficient clearance

 

[Scvintage]

Re:

On my cannondale that’s the problem. I have an aftermarket headset reducer the makes everything just too tall. Reducers add 1~2” to headtube, ad in headset and my Judy. Xl can’t even fit, not even close. It’s pushing me into a customize it corner.

 

[My_Teenage_Self]

1.5" external headset should fit that headtube tube? Get a works or similar one to give 1-2 degrees less headangle.

Honestly though, lots of effort for almost no real gain.