70+, very tall frame geometry

[einguterfreundvondir]

Dear Frame builders,
I desperately need a custom frame because of my special interests in bikes and probably because of my 6.6-foot size, too. As I have some experience with metal, I would like to take the chance to learn something new and add frame building to my passion for bicycles. I have two 66-cm-tall classic road bikes, but I'm thinking of a different type of bike and an even bigger frame to suit me.

I would like to share with you my latest "geometry sketch" and ask for advice for the first time.

About me:
203cm tall, 108kg light, shoulder 41cm, arm 67.2 cm, sternum height: 167.3 cm, inseam: 102cm.

From time to time, I ride my bikes on up to 130 km of relaxed tours on pavement or "off-road" as well as daily for commutes in the city.

About my dream bike:
All-road, classic, rim break, touring/gravel/randonneuring bike with at least 40mm + fenders tire clearance, pretty short and upright comfortable. Lively feeling and more stable riding with the front randonneuring bag installed. I want to ride the bike on pavement roads for longer tours and through forest roads on weekend rides.

Main thoughts about geometry:

• 700c because 650b seems very small and creates weaker diamond frame? (although i love my tall 26" MTB)
• 75 ST angle for less setback and center of gravity
  
• 72 HT angle for more Tire to DT clearance and stable ride characteristics
• 73cm c-t ST length to fit my size...
• Horizontal TT for a classic look and shorter steatpost
• 58cm TT length, because 60cm on my existing bikes leads to a very short stem for me
• 45cm CS length for a longer, stable Wheelbase and tire clearance
• 7.2cm BB drop, what the guy from Breadwinner suggests as the sweet spot
• 180cm cranks for my long legs
• OS down tube 31.8 for more stability
• 5cm trail for liveliness but a stable feeling with front panniers
• T/TT/DT/Fork lugged, but BB fillet brazed because of special geometry needs.
  
  
• 

Will I need a diagonal tube from the bottom head lug to seat lug or dropout to head tube for extra frame stiffness?


I am very thankful for all of your suggestions, ideas, warnings and criticism!
I need some advice, as at this point everything is self-taught and you don't know what you don't know :-)

Thank you from Munich, Germany
Kind regards,
Michael

[Mark Bulgier]

That design should be fine, I don't see much that's too far out of the mainstream.  The seat tube angle is a bit steep, true, but I feel that's a feature that people obsess too much about.  You can adapt to it.  It certainly won't hurt your "efficiency" (however that's measured), and you can ignore anyone who tells you need a shallower angle for "power output". As evidence I point to all the records that have been set at every distance with very steep angles.  I put one top  local racer on an 85° STA, and he broke his personal record on it on his first time out.  That extreme angle was for a track bike, specifically kilo time trial, and event that only lasts one minute, so comfort isn't in the equation at all.

For relaxed riding ("touring"), many people like a shallower seat angle to better balance the force on the saddle, pedals and handlebars.  Steep STA may cause you to put more weight on your hands, maybe a problem if your hands, wrists, arms or shoulders are the thing that gets most sore or tired on your longer rides.   Maybe you can mock that up on one of your current bikes, with a seatpost flipped front-to-back so it moves the saddle forward, so you can test the steep STA before committing to it.

If you reduce the STA, be sure to check for toe overlap.  Measure the Front-Center (BB spindle to F. wheel axle) and subtract your crank length, amount of foot forward of the pedal axle, and radius to outer extent of the fender.  Overlap is not (usually!) fatal —  I have bikes with toe overlap, but it can be annoying, especially on a loaded touring bike.  It's probably not too hard to design for positive clearance on such a large bike, but the short toptube could put you in overlap range if you make the STA slacker, especially if you go to larger tires.

I strongly believe you should not use extra bracing tubes, like in your 2^nd and 3rd drawings. Just make the tubes large enough in diameter, and not too paper-thin.  Your suggested 1-1/4" DT and 1-1/8" TT are probably big enough, just don't use the thinnest gauges available.  Consider .9/.6 butted, which used to be considered thin not too many years ago, and which is fairly safe for beginner FBs to join without overheating.  (You will still need a lot of brazing practice on scraps before you make a frame for riding though.)

I didn't see if you called out the steerer size.  I'd strongly recommend 1-1/8".  I still use 1" steerers, but I'm a stubborn retro-grouch, and even I can admit that there's a place for "oversized" steerer/headset.  You might even consider a fork with a tapered steerer, 1-1/2" at the bottom.  I don't know of any lugged crowns made for that steerer (maybe someone here does), but at least now there's a great head tube lug for that, made by our own Alex Meade.  1-1/2" steerer is overkill in steel; it's mostly for cabron-fiber forks, but you might consider it if you want to put steerer flex and/or failure well out of your mind.  

Duane Draper is a FB on this list who made his own lugged-crown for 1-1/2" steerer.  He cut up a lugged crown made for a smaller steerer, and fillet-brazed the lug sockets to the steerer.  Not sure I'd recommend that to a beginner FB; forks are one place you do not want to experiment with unproven designs, unless you really know what you're doing.

So anyway, the 1-1/2" steerer idea might be crazy.  Maybe I just like it because of the Alex Meade lug!  Don't go inch though, I've seen too many inch steerers that snapped off from fatigue.  You can't inspect for incipient cracks very easily since they are hidden inside the head tube, so the for snapping usually takes you by surprise.

Consider using slightly curved chainstays, like the ones Rene Herse cycles sells, or even MTB stays, to allow fatter tires.  The extra clearance doesn't hurt you any if you choose to use skinnier tires, but someday you'll be glad you left more room.  I'd try to make it fit 48 mm tires minimum, and maybe consider going to 50 or 55 mm if you can.  Yes even for a road bike.  I'd make the chainstays even longer for such a big bike, but 45 cm is probably good enough.  A narrow "Q-factor" (horizontal spacing between your feet) is somewhat at odds with the widest rear tires, but at your height, a narrow Q is less important than it is with short people.  Anyway some people prefer a wider Q; narrower is not necessarily better.  Especially at your size, wide tire clearance should take precedence over narrow Q.

That's all I got for now!  Have fun, and keep us posted.

Mark Bulgier in Seattle WA USA

[DancesWithCars]

At your height 

would you consider 29" wheels?

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[Reed McFarland]

700c and 29” are the same thing. He might be one of the few who could benefit from 36” wheels though. Or the new “750D” size that WTB came out with earlier this year. ERD on that is 660, 700 is 622, so 38mm larger. 

Reed McFarland

On Nov 28, 2023, at 8:15 PM, DancesWithCars <dancesw...@gmail.com> wrote:



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[DancesWithCars]

Damn metric

And there are so many 26 variations

I still read C like CentiMeters 

Or Drone battery pack

capacity

Realized after posting and 

not a lot of undo ability by then

Already stepped in it 💩...

While down rabbit 🐇 🐰 hole of history 

of first mountain bikes

A reread of 29" Gary Fisher

Et. Al. history and remembering 

my Peugeot frame break

Going mountain GF Mamba heavy

 now my Beater bike from 1998

older than most kids 

in youth/community LBS

A visit to a Big & Tall like bike shop?

Builder? Try some non COTS

 (commercial off the shelf) stuff?

i. e. Shaq's (BIG US basketballer etc

7"1' 325 lbs on

https://en.m.wikipedia.org/wiki/Shaquille_O%27Neal

as Listed Weight

) bike etc?

Like going to Single speed (first time)

 learning to ride again

 to ReImagine it?

Fat tire bike? 

Convert with a different wheel set?

And excess as first time building 

wiggle room / safety factors? 

As likely aware

A loaded touring bike is a different animal

 to ride loaded 

(Go heavy or go home?

(But I'm already home (quibbling?)),

Taking groceries 25 miles back?

Hauling water to primitive camp site

 for a few days off bike

Ironically called rainy days etc)

But you may have Alps nearby...

And riding without gear if usually do

similar "responsive" /springie / light 🪽 

feelings?

How much gear ?

Ultralight?

Full tool set?

For SAGging others?

W/o moto? 

Add rider weight again? 

Say 2x rider and see if 

computer model holds? 

Build for eBike future?

(maybe sacrilegious in 20's 

but 40's to 60's

 consider foresighted?

aka aging in place on wheels 🛞 🎡

Wheelchair ♿)

Width and frame taking motor?

(Pop a Swytch kit in/on?)

 (where? Maybe Mid 

but add later?

Wheel? Extra clearance

Rim + disc compatible?

Tubular ready AlexRims?

Some frames 

easier to build production 

Both options, single run /spec 

To Which caliper mount standard(s)? 

My Montague designed

 Swiss Bike licensed? 

 is mixed

Disc front,

 rim rear 

with Boom (aircraft aluminum )

 top tube folding

and they now have

 a rear rack rotate down

converts to stand

Patented, sigh...

S&S couplers?

Where would you put If say

touring overseas?

Or no rack as alt / no SAG available

way back? 

Or braze on for Ham antenna 📶

Riding Club flag carrier/officer?

Maybe next build from prototype/

base/brazing/TIG practice #1...

+/- Rolloff sp? (internal gearing?) hubs?

Belt drive mentioned on other first?

 build thread...

~5x overbuilding say with aluminum?

Gets brittle

Oddly titanium?

Cost? Availability?

Or stainless?

Welding v. Brazing skills?

TIG for fun?

Bamboo 🎍 mock up?

Wooden hobby horse mock up

 as mentioned?

For sizing?

Steel practice #1?

CroMoly#2

Stainless#3

Aluminum#4

Titanium #5

Composites #6?

... 

Carbon/composite options?

After flexibly designed frame build 

could substitute lighter components, fork, etc? 

 for some after the fact 😘 weight redistribution?

Like shaving a (wood) violin 🎻 or

Guitar 🎸 for tone/vibration

Mechanical engineers seem to like frequencies/

Vibrations, what's that rattle

drives some nuts...

Weights added to handlebars 

only go so far...

Things to consider on paper?

CAD?

Might shake loose any other issue(s)

wants/needs...

Diagrams seem odd

Maybe stick figures for angles 

missing some stuff

Say heavier drop out/ wheels 

up tube capacity going to it?

Tube thicknesses

Lugs

Drop out sizing

Flesh out the skeleton and

 see if sort of meatiness looks right? 

Toes and turning

as already mentioned

Cleats +/- cages? 

Rake seemed weird but maybe just

my stick figure reading ability

We've got BikeToWorkDay t shirts figures 

(Ironically girls bikes went pink

and then reused next year... )

that don't look rideable

but this is Wa(r)shington, DC USA

PoliDicks town so some 

what MIT might call hype

(Infinitesimal calculus)

others maybe circus in town

aka elections...

HTH

Age mentioned?

Pull gear/ kid trailer capable?

Utility functions as well as 

80 mile days?

Lights?

Dynohub sets?

Solar?

Ham radio?

Like Computing across America? 

WinoBike? To Lin(ux)Bike

Behemoth 1&2?

Both 

Bents iirc

And frame N+1?

Start thin (or thick steel?)

small practice

like writing a book

Second++ really readable/

useable/marketable 

etc...

[Duane Draper]

Thanks Mark.  Yes it was a bit of work and the first 2 attempts were cut up (testing) or scrapped (something slipped and it ended up mis-aligned). This would be challenging for someone new to fabrication.  However, I’m frequently amazed at some of the FS designs new folks take on though!  Forks aren’t where I started practicing.

 

I like the look of the finished product though.  Here’s a shot of it cutting the crown race after powder coat with rack mounts on the front (you will want sun glasses!): https://flic.kr/p/2pgzXPY  Full pictures are coming.

 

To the OP, I might also add that a degree or so of upward and forward slant to the top tube won’t detract from the aesthetics you are looking for but will provide a little higher bar position without a super long stem.  This will allow you to add a bit to the top tube length.  I agree with Mark that overlap might be a problem with that top tube length, long cranks and what I assume are proportional feet! 

 

Keep us posted!

--

[Cliff McLeroy]

Unless you are into the "planing" effect, I would definitely recommend double OS tubes given your weight and the size of the frame. This would be 28.6 steerer, 35 DT, 31.8 ST & TT. This would be a much more efficient way to add strength and stiffness than a mid tube. There are some, but not as many lug & BB shell options for these sizes. I would be cautious about that steep ST angle unless you are already riding 0 setback posts with the seat clamped forward. I'm long legged as well and I'll be moving in the opposite direction. I always run posts with setback and the saddle is usually clamped rearward. So for future bikes I'm going down from 73 to 72 of even 71.5. If I'm too far back I can simply use a zero setback post. Lastly with that 73 cm ST length, you'll likely need a non-standard tube. With a standard 28.6 tube, you'll probably need to use straight gauge 28.6x0.9 mm tubing, which will require a non-standard 26.6 post. If you go up to 31.8, there will be more options that will get you closer to that length such as a butted DT. You'll just have to plan on a shim or oddball seatpost size.

-Cliff McLeroy

[Jon Norstog]

Cliff, list:

I wanted to ride the Oregon Outback and built a frame with those same tube sizes.  I am not extraordinarily tall or heavy - 6'0" and 200# but I wanted a frame that would stand up to hard riding with a fairly heavy load.  I used fillet-brazed 853 tubing, including the seat tub and fork blades, 8-5-8 DT and 7-5-7 TT.  J&B offers a pretty decent micro-adjusting seatpost in 30.4mm which seemed a good fit in the ST.  The frame is a little on the stiff side for me, but not excessively so, and has become my daily ride on the streets and highways.

A bonus with the pricey 853 tubes is they are quite a bit more resistant to dents and dings than cro-moly, even the heat-treated stuff.

Good lick.

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[good friend]

    Lots of good thoughts already, however...
I am a bit curious about the suggested top-tube length
   There are different ride styles, the lean-over versus the upright being the most obvious, but there is also the desire for a ride feel where you are "contained-within" the gravity of the bike "versus" the feel of being "above" the bike, whether you like the front wheel to be under you or ahead of you...    One thing that differs between people is, well, is your main center of perception in our body or your head?   that would perhaps change how you experience a bike fit...   There are various ways to describe these differences, but top-tube length can dramatically effect the feel of the ride.    
    I say this because, while I'm not sure where the end-points of your arm measurement is, I would have expected the top-tube length to be a bit longer...

Personally I like shorter stems so that I do not feel like I am way out ahead of the bike...   but I tend to ride more up-right, not a racer...

noMadic  Thomas

[Cliff McLeroy]

Yea, I'm 5'10", 145 lbs and I've done several with 35 or 38 mm DTs and they feel great to me. I've always felt like tires, bars, seat and post affect ride more than tube diameters in a diamond frame.

On Thursday, November 30, 2023 at 11:04:32 AM UTC-5 Jon Norstog wrote:

Cliff, list:

I wanted to ride the Oregon Outback and built a frame with those same tube sizes.  I am not extraordinarily tall or heavy - 6'0" and 200# but I wanted a frame that would stand up to hard riding with a fairly heavy load.  I used fillet-brazed 853 tubing, including the seat tub and fork blades, 8-5-8 DT and 7-5-7 TT.  J&B offers a pretty decent micro-adjusting seatpost in 30.4mm which seemed a good fit in the ST.  The frame is a little on the stiff side for me, but not excessively so, and has become my daily ride on the streets and highways.

A bonus with the pricey 853 tubes is they are quite a bit more resistant to dents and dings than cro-moly, even the heat-treated stuff.

Good lick.

[einguterfreundvondir]

Hello everybody,
thank you very much for the very helpfull and encouraging feedback!
I'll keep you posted with a new iteration considerin your suggestions.
In the meantime i would like to share with you the bikes i ride the most beside my borring treking commuter.

1. Dancelli 66cm roadbike
build a bit more durable. It's the fifth time i rode L'eroica with this bike.

My problem is the long seatpost and setback due to STA as well es the short stem due to TTL because of my prefered upright position. And of course tire clearance and very lively handling.

2. Sloughi 66cm Touring bike
More tire clearance and more stable ride quality but even 62cm long TT and a lot of inflection over the BB when pushing into pedals with force.

3. Razesa tall MTB
I absolutely love this bike but it feels like falling off from behind and like there is no Trail availble at all.

My personal main goals for the new frame is shorter TT, less setback and stronger Frame trangles. Your ideas pretty much consider all of those points, thank you!

Greetings,
Michael

[Cliff McLeroy]

Michael,

Nice looking bikes. I wonder if your fit problems might be better resolved with raising the bars. I didn't look at the measurements you posted but I imagine you have a bit larger leg/torso ratio than typical, and this makes it difficult to get the bars in the right position. I'm considerably shorter but have this issue, as well as the need for a more upright position simply due to age. I keep the bars at roughly the same height as the seat, and with my proportions I need a really crazy stem on most production road bikes. On my builds I do a really long HT and steerer which allows me to use most off the shelf stems flipped to give rise. I also do a lot of slope on the TT for clearance and compliance with a long mtb post. It doesn't have the classic look, but it's comfortable for me:

https://www.flickr.com/photos/cliffsbikes/44946051202/in/dateposted-public/ 

[good friend]

Cliff, I really like the fork crown one image to the left of the bike
picture you linked:
https://www.flickr.com/photos/cliffsbikes/33849538868/in/dateposted-public/
It looks like you made it with a rectangular "tube" and standard
fork-blades, I'm curious and hope to hear how you accomplished the
steer-tube and crown race...    I do not see any braze on the race area,
is that due to the lathe making the diameter perfect for the race, or is
it due to some other construction technique...   I see a thickness to
the brake/fender bolt hole and not easy to see in that shadow area if
there is any braze...    is it maybe just a thick-wall tube that you
lathed thinner for most of it's length ??

noMadic  Thomas




On 12/1/23 08:02, Cliff McLeroy wrote:
> ... On my builds I do a really long HT and steerer which allows me to

[Cliff McLeroy]

Thomas,

Thanks! For that one I started with 1.125 x 0.058 round tubing and .875 x 0.035 square tubing. I brass-brazed the square segments to the round tube with enough length to cover the blades. I then chucked this in my mini lathe and turned the section just above the segments down for a 27.0 race, and about 1" above that to 26.8. This provided an external butt for the steerer, adding about 0.7 mm thickness. Then I trimmed it off and slipped a piece of 1 x 0.058"  tubing inside as the actual steerer, brazed with silver. The blades are 24 mm round track blades and the mitering of the segments was a little tricky since I left the top side to cap the blades. It came in at 640 grams so pretty light but not extreme. If I were building it for someone else I'd build it a bit heavier, probably with a butted steerer and standard crown race. My external butt is pretty close to the cups, so I would not want a headset swap down the road to cause problems.

-Cliff

[Doug Fattic]

Michael, I’ve had several students from Germany take one of my framebuilding classes.  One of them even took another class in Germany before he came to mine.  I don’t think any of them are near Munich however.  I’ve also had a couple of apprentices that were about your height.  I recommend that you base your frame design on your seat/handlebar/pedal relationship for the purpose you are going to use this new frame.  Most likely this needs to be done on some kind of stationary fitting bike.  Doing it on a regular bike will be too restrictive.  If you do that, what I think you’ll discover is that your seat angle is too steep. 

Most fitting recommendations are based on maximum performance emphasizing speed over comfort.  There are 3 major elements of fit – biomechanical efficiency, aerodynamic efficiency and comfort.  Those 3 things are in competition with each other and comfort is often dominated by the other 2.  However the kind of riding you are planning seems to prioritize comfort.  That means your handlebars will probably be a bit higher and closer to the height of your saddle.  And maybe a bit closer to your seat too.  Correspondingly as your handlebars go up, your seat will need to go back. This is why all those European utility and commuter bikes have such shallow seat angles when they are sitting really upright.  Furthermore a comfortable ride means your weight is balanced over your pedals taking the weight off of your arms, hands and upper body.  You can find this magical position by estimating where your bars will be (on a fitting bike) and then slowly move your seat back until you discover that when you just lift your hands slightly off the bars or hoods, your upper body is not straining to hold that position.  Voila!, your weight is balanced over the pedals.  Now you can fine tune where your hands will be in relation to your seat.  Probably your back will be around a 45º and your arms 90º to your back.  That is just a big generalization – we are all different.  As a fitter (particularly of good recreational cyclists) I know everyone is not in the middle of the Bell Curve so those refinements can be found by handlebar position adjustment.  Most people can verify to a centimeter or so where they prefer their bars to be.  Of course that can change for a variety of reasons. 

What I will bet is that if you choose the position where your body is balanced over the bike, your seat angle with a setback seat post will likely be in the 72º range.  I’m sure it won’t be 75º.  That is the seat angle you would use when positioning yourself to go as fast as possible (aerodynamics and all that) and damn the comfort. And your hands on your handlebars will be much lower than your saddle.  Over many years I’ve developed a fixture I use on a flat table that converts a bicycle position into a frame design.  This fixture I have laser cut and etched out of stainless steel in Ukraine.  Google Ukraine Bicycle Project and you’ll find it.  When I place the chosen seat and post in the same position on the fixture that I found in the fitting, it has an accessory that shows what the seat angle is supposed to be.

And now a few more comments on seat tube angles. A production bike’s emphasis is usually on positioning for speed because that’s what sells.  Their lawyers also dictate that a rider’s toes miss the front wheel when pedaling.  One of the easiest ways to do this is to steepen the seat angle to push the front center further forward. For many recreational cyclists that places them out of their best position.  What they should do is use smaller wheels. A custom frame design almost always involve compromises.  But I digress.   

My 2^nd suggestion is to use a regular socketed BB shell.  You can adjust the angles on those without too much difficulty.  Sockets makes it much easier for a novice to get the right chain stay length so your wheel will center.  You can slide the chainstays in and out of the socket much easier than trying to miter them to the exact length.

The 3^rd suggestion is that you can angle your top tube slightly up to better fit the angles of your seat and top tube lug.  While it is possible to blacksmith a lug and show it who is the boss of its angle, it just makes sense to angle the top tube a degree or two to match the lug angle.  As already mentioned this off level adjustment is hardly noticeable.  It is much easier for a beginner not to play blacksmith on lugs.

Discussing the front end variables would make this very long post beyond any reasonable length.   

Doug Fattic

Niles, Michigan

[mmanning]

I have been tempted to reply to this thread, and now since Doug has given some sage advice I can't resist. To comment on the suitability of the proposed frame design I would want to know the dimensions in the diagrams below (an existing bike set-up, and the rider's body measurements to see if that makes sense), and also to be sure of the wheel and tire size that will be used. That will be important for getting the clearances for fenders, which I would guess shouldn't be less than about 40mm between tires and the shoe toes or frame tubes. 180mm crank arms means that the BB drop should be reduced a bit to avoid pedal strikes.

Martin Manning

[einguterfreundvondir]

Hello everybody,
thank you very much for the detailed feeback! i would like to respond to the great bike fitting feedback first.
This effects the seatangle, TT lenght, handlebar height and general "seat/handlebar/pedal relationshop". This is a very important topic and i am thankfull for your honest feedback, as i have had a bikefit for my trecking bike. In addition to those numbers i wanted to rely on my own feelings and comparison with current bikes, but this could be a trap considering your experienced thoughts...

In generel I would want to raise my handelbars to saddle height, what will propably change my feeling abou the fit. besides this on all my bikes with a 72% seat angle I have the feeling of sitting very far back and almost falling backwards. I already use a 0mm offsset seatpost and often put the saddle as far forward as possible. I also have the feeling that I have to sit a little further forward for pedaling power and the position of my knees over the pedals.
With my height and weight, the long seat post with flat angles has a lot of flex, which is uncomfortable to me sometimes. The slacker the angle, the stronger the effect. So my intuition was to make the seat angle steeper. A longe ST will propaby minimise the flex. I show you here a consideration in which with a 72 degree seat angle the reach is extended by 5cm. For comparison, a 58cm long seat tube with an equally 19cm long "seat post plus saddle" would be 5cm further forward. I compared those numbers to see what my body height and ST lengh has an effect on setback. I'm worried that these 5cm plus the longer TT according to your feedback won't improve my feeling of falling over at the back, "suspension" and too long a reach. Or am I mistaken? Probably only a new bike fitting can clarify this. I'll share my body measurements and the requested bike parameters on the model for you to use your precios time helping me out :-)

About me:
203cm tall
108kg light

shoulder 41cm

arm lenght 67.2 cm
sternal notch: 167.3 cm

Fermur lenght: 57cm (self measured)

inseam: 102cm.

 

This was the result from my Bike fit and here are some added Bike fit measurements in red. They prettty much suit the bikefit.

Thank you very much! Michael

[Doug Fattic]

Michael, my philosophy of frame design is based on the results of a fitting and - if possible - trying that fitting out somehow actually riding with it. In fact my primary fixture is like a full scale drawing that can hold a saddle/seatpost as well as stem in the same position that resulted from the fitting.  As mentioned before your seat/handlebar/pedal relationship will be heavily influenced by the kind of riding you want to do.  In other words if maximum performance is your goal then your position will be different than if you primarily want to be comfortable.  This is reflected by the height of your handlebars compared to your saddle.  And the point I want to make is that there is a relationship between your handlebar height and your saddle set back.  The higher your saddle, the further back your saddle needs to go.  This is why time trail bikes have steep seat angles and upright utility bikes (in the States we call them Dutch bikes) have very shallow seat angles.  In your case since you want to raise your handlebars to be more comfortable, my recommendation is that at the same time your push your saddle rearward too. 

Many if not most bike fitting philosophies place an emphasis on performance.  How to position you to go faster.  However for some people their goal is to sit more comfortably.  This can likely happen as we get older and fatter and less flexible.  But this can also be for someone of any age that is commuting or enjoying the journey listening to the birds and looking around.  This is where saddle setback comes into play.  For those that put a priority on comfort, they will want their weight balanced over the pedals.  They do not want to be using there body core and arms to be holding up their weight (something that is of no concern to a skinny racer).  You can find this balance point on a stationary fitting bike.  You discover where it is by slowly inching your saddle backwards (an English expression that means slowly and carefully) until you notice that when you lift your hands slightly off the bars (which are probably at saddle height) you no longer have to use your upper body and arms to hold up your body weight.  You are balanced over your pedals.  Once you have found this saddle setback position, you can adjust the height and reach of your handlebars  That is a separate discussion.  

Now it is quite possible that you might want to have a middle compromise between all out speed and relaxed comfort.  For example in your case you did not like the feel of a 72º angle.  In that case you might be wiling to accept some weight on your hands.  These nuances are why it is not possible for me to provide much advice on what is the best saddle setback position for your specific case.  I just wanted to make sure you were aware that raising your handlebars probably required moving your saddle back some.  

Here is a picture of my Ukrainian made fixture showing how I design a frame based on a fitting session. 

Doug Fattic

Niles, Michigan (Niles is just over the state line from Indiana and a few miles north of Notre Dame University)

[Cliff McLeroy]

Michael,

If you have that "falling off the back" feeling have you tried tilting the saddle forward some? I tilt mine forward considerably more than most people, mostly to relieve pressure off the "boys" but also to avoid that falling off the back feeling. Most people say to position the saddle level and only tilt it slightly. But since the weight is mostly on the back part of the saddle, it will tilt rearward, sometimes quite a bit if you have Ti rails or a lot of exposed seatpost.  

-Cliff

On Tuesday, December 5, 2023 at 5:42:59 PM UTC-5 einguterfreundvondir wrote:

Hello everybody,
thank you very much for the detailed feeback! i would like to respond to the great bike fitting feedback first.
This effects the seatangle, TT lenght, handlebar height and general "seat/handlebar/pedal relationshop". This is a very important topic and i am thankfull for your honest feedback, as i have had a bikefit for my trecking bike. In addition to those numbers i wanted to rely on my own feelings and comparison with current bikes, but this could be a trap considering your experienced thoughts...

In generel I would want to raise my handelbars to saddle height, what will propably change my feeling abou the fit. besides this on all my bikes with a 72% seat angle I have the feeling of sitting very far back and almost falling backwards. 

[M-gineering]

Is it the saddle position, or the wobbly feeling caused by all the
weight on the rearwheel (you should ignore the '1 meter' crowd and use
some proper long chainstays) and very little on the front?

--
mvg

Marten Gerritsen

Kiel Windeweer
Netherlands


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Tubes & Coffee
Zondag 17 December weer de traditionele open dag in de werkplaats

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[good friend]

I have often wondered why the "arbitrary" length between the wheels was
so static when people range so far in height...
   I'd recommend looking at longer rear stays
instead-of/as-well-as/before changing the seat-tube angle...

noMadic  Thomas

[mmanning]

Michael,

Are the arm and femur lengths you posted measured as shown in the diagram posted above? Your saddle height seems long compared with your inseam. I'd expect it to be ~4 cm lower. Is your pedal stack height more than the typical 30mm?

How long is your bare foot? What size tires are you wanting to run? 700 x 25? 28? 30? You want fenders, so the required wheel clearances will push things out.

For the wheelbase, I think definitely it should be well over 1m, but I think weight distribution should be kept in the typical range, with the CG somewhere near the crank center. If there are no errors in your measurements, it looks to me like 73 degrees would work for ST and HT. 

[njh...@gmail.com]

On Wednesday 29 November 2023 at 12:55:13 pm UTC+11 Reed McFarland wrote:

700c and 29” are the same thing. He might be one of the few who could benefit from 36” wheels though. Or the new “750D” size that WTB came out with earlier this year. ERD on that is 660, 700 is 622, so 38mm larger.

Conor Dunne, ex-pro cyclist who is 2.04m (6'8") tall, had an interesting video on GCN+ a couple of years back titled "Reinventing the Wheel", where he had a bike built for himself around 36" (BSD 787mm) wheels. Unfortunately GCN+ as a streaming service is now defunct, due to Warner Bros pulling the pin on it, but you can still see the trailer for the video on their YT channel (https://www.youtube.com/watch?v=dZDdQ1V45Ow), and there's a bit more showing the bike being ridden here: https://www.youtube.com/watch?v=XfAzmW0LDNw.

Nick Payne