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joy of vaping
joy of vaping's picture

possible SQ: Do fitters measure or check for actual weight distribution?

Wed, 11/11/2015 - 12:26
NOVELTYNAME
NOVELTYNAME's picture

@amy

"Folks want options!"

Wed, 11/11/2015 - 12:57
rauce
rauce's picture

Never heard of it being quantified specifically. I've been a "fitter" at bike shop, but we had a low tech approach. maybe someone who knows more about retul etc. could chime in.

I did consider it when I fit people though.

Wed, 11/11/2015 - 13:15
yummygooey

my fitter didn't. he provided me frame stack/reach and other key dimensions but i don't remember him saying anything about weight distribution.

that said, is it time to bust out my free body diagrams to figure out the bike + rider + luggage weight distro on a frame design? sounds fun.

Wed, 11/11/2015 - 13:33
catdrew f

No, I've never heard of someone using weights like corner balancing a car

Wed, 11/11/2015 - 14:03
lukasz
lukasz's picture

If I were doing it again I'd have clearance for 2.25 tires, fork a-c that matched a production carbon fork, and maybe a tapered head tube (for said fork). I guess the tire clearance is actually the least important of those since there are enough 2.1 and narrower tires to make me happy. I have 78 drop and 180 cranks. No problem.

Wed, 11/11/2015 - 17:05
yummygooey

i have thought about the carbon fork deal a few times in the past but yes, it seems like all the good disc options come in the tapered flavor only.

how did that ritchey work for you?

or just take the dive and go for the tapered...

Wed, 11/11/2015 - 17:19
crowding
crowding's picture

I tried to work out my weight distribution by sitting on the bike with one wheel on a block and the other one on a bathroom scale. Not sure if it makes that much difference to design. Most people will have a rider CG that's horizontally close to the BB center anyway.

Wed, 11/11/2015 - 17:34
NOVELTYNAME
NOVELTYNAME's picture
(Reply to #109)

yummygooey wrote:
take the dive and go for the tapered...

"Folks want options!"

Wed, 11/11/2015 - 18:15
yummygooey

know of a tapered needle bearing headset?

Wed, 11/11/2015 - 18:17
NOVELTYNAME
NOVELTYNAME's picture

F u

"Folks want options!"

Wed, 11/11/2015 - 18:48
lukasz
lukasz's picture

The fork is pretty good. No complaints. It probably derped the geo good because the A-C is 20mm+ more but honestly I didn't notice anything weird when riding. I'd just get the bike designed around a slightly taller A-C than seems necessary like Fred did on his Elephant. Go tapered tho, especially if you can get that nice head tube like Eric E. used on that purple track bike.

Wed, 11/11/2015 - 19:57
yummygooey

i'll look into the tapered stuff. i think it sounds rad, but realistically i'm probably too lazy to swap forks around.

updates:

geo1_rev3 by yummygooey, on Flickr

geo2_rev3 by yummygooey, on Flickr

Wed, 11/11/2015 - 20:03
ergott
ergott's picture

We're practically bike twins!

If someone on here did it, I'd probably like it. Since it was done by someone I don't know, they're a fucking idiot.

Thu, 11/12/2015 - 06:21
rauce
rauce's picture

Here are my current framebuilding projects:

Thu, 11/12/2015 - 13:13
catdrew f

I like a shorter f-c on the road but I think your torso is longer than mine

Thu, 11/12/2015 - 13:42
euclid
euclid's picture

why the offset stays on the track bike?

Thu, 11/12/2015 - 14:12
rauce
rauce's picture

I think your reach is still greater but it's our starting positions that are so different, I only run ~8cm of setback cause short (relative to leg length) femurs and slammed cleats so in order to get the bars 61-62cm from the tip of my saddle with bar drop of 14-15cm I need a frame with quite a lot of reach.

I noticed though that it still has 45mm rake when it should be 43mm.

Really looking forward to finishing that road bike. Designed around steel frame/fork 1" threadless and 7/4/7 OS tubes. Got these cool short point lugs with cast fastback sockets like how zanc used to do them. Finished product will look a bit like this:

I already have the fork for it, marinoni did it for me to my spec unpainted.

Thu, 11/12/2015 - 14:23
rauce
rauce's picture
(Reply to #119)

euclid wrote:
why the offset stays on the track bike?

A smaller rear triangle should in theory be a bit stiffer. Also, I'm using the cast samson track dropouts and although the seatstay piece articulates a little bit it works better with a smaller cs/ss angle.

It's not possible to show in rattlecad but it's lugged and there will be small sleeve of tubing around the ST to reinforce the area where the SS join.

Thu, 11/12/2015 - 14:31
yummygooey

what are the tube diameters for "OS"? 28.6 TT and 31.8 DT?

Thu, 11/12/2015 - 14:33
rauce
rauce's picture

Yeah

Thu, 11/12/2015 - 14:36
catdrew f
(Reply to #122)

rauce wrote:
I think your reach is still greater but it's our starting positions that are so different, I only run ~8cm of setback cause short (relative to leg length) femurs and slammed cleats so in order to get the bars 61-62cm from the tip of my saddle with bar drop of 14-15cm I need a frame with quite a lot of reach.

I noticed though that it still has 45mm rake when it should be 43mm.

Really looking forward to finishing that road bike. Designed around steel frame/fork 1" threadless and 7/4/7 OS tubes. Got these cool short point lugs with cast fastback sockets like how zanc used to do them. Finished product will look a bit like this:

I already have the fork for it, marinoni did it for me to my spec unpainted.

yeah i run 66 or 67cm to the bars

lemme find my kirk chart

Thu, 11/12/2015 - 15:01
catdrew f

Thu, 11/12/2015 - 15:03
JUGE FREDD
JUGE FREDD's picture
(Reply to #124)

yummygooey wrote:
my soma is low 30s as well and i wish it were a bit more stable with no hands, hence targeting 37. bag is a large swift industries ozette on a haulic colin rack...

for a number of reasons that rack and bag do not work well together

the stock 10x12 Colin rack really only works with the XL, and the XL only works with it

yummygooey wrote:
how does bb drop affect my ride? i thought more drop meant more stable, which sounds like a good thing?

it does and is pretty rad for a low trail bike that doesn't have any trouble zipping around corners

it also makes your super tight prolly-stanced chainstays harder to pull off

It's a struggle, but you cut out his tongue, and his last words are "atmo atmo Atmo ATMO ATMOOOOOGORIHGGHRSHGGRLMGGMMGMgrrglegurglegrr....."
– akasnowmaaan

Thu, 11/12/2015 - 21:44
JUGE FREDD
JUGE FREDD's picture
(Reply to #125)

lukasz wrote:
The fork is pretty good. No complaints. It probably derped the geo good because the A-C is 20mm+ more but honestly I didn't notice anything weird when riding. I'd just get the bike designed around a slightly taller A-C than seems necessary like Fred did on his Elephant. Go tapered tho, especially if you can get that nice head tube like Eric E. used on that purple track bike.

the 1 degree change in geo is perfect for the application switch

both yours and mine give same +20mm derping, remember my Trigon fork is taller than the new Ritchey

I wouldn't go tapered, it won't be as weird with a nice custom unicrown steel fork, but still somewhat pointless and chunky

It's a struggle, but you cut out his tongue, and his last words are "atmo atmo Atmo ATMO ATMOOOOOGORIHGGHRSHGGRLMGGMMGMgrrglegurglegrr....."
– akasnowmaaan

Thu, 11/12/2015 - 21:48
yummygooey
(Reply to #126)

JUGE FREDD wrote:
yummygooey wrote:
my soma is low 30s as well and i wish it were a bit more stable with no hands, hence targeting 37. bag is a large swift industries ozette on a haulic colin rack...

for a number of reasons that rack and bag do not work well together

the stock 10x12 Colin rack really only works with the XL, and the XL only works with it

i know - but i haven't actually heard of anyone complain about using the large ozette on the HC rack. i even know of some using a small ozette on the rack.

i'm sure you can imagine how derpy the XL will look as an every day bag on a bike my size, in addition to the incompatibility of the bag with the shimano hydro levers on 42cm bars.

Thu, 11/12/2015 - 22:46
blackholelectron
blackholelectron's picture

As someone in XL ozette-small NFE crü it can look kinda derpy but eh, I have a huge bag, fuck the haters

Chainstays are 440 and BB drop is 70- I'm not sure if the stays really could be shorter without serious fuckery running road Q cranks, but that's not a huge issue if you don't plan on doing that. There was the whole dimpling issue with batch 1 NFEs, and Glenn seemed pretty reluctant to do any kind of modification at all, but that could very well just be a personal thing of his so possibly your custom will be able to accommodate that

BB could definitely be like 5mm lower IMO

Quote:
if you're happily shuffling between rural corn dog purchases at 14mph, how are your needs not being met?

Fri, 11/13/2015 - 13:13
JUGE FREDD
JUGE FREDD's picture

for starters the NFE has much more tire clearance

mine is 435 but could easily have been 425 by trimming the dropout end more

it's using a Dedaccai s-bend chainstay tho, and there a few more styles beyond that and the Nova

It's a struggle, but you cut out his tongue, and his last words are "atmo atmo Atmo ATMO ATMOOOOOGORIHGGHRSHGGRLMGGMMGMgrrglegurglegrr....."
– akasnowmaaan

Fri, 11/13/2015 - 15:39
jeffro
jeffro's picture

This thread is one of the best. What I've learned from you wizards has inspired some tinkering in my workshop, and I'm enjoying at least one of my bikes in new and better ways. Thanks, guys.

Fri, 11/13/2015 - 15:57
yummygooey
(Reply to #130)

JUGE FREDD wrote:
for starters the NFE has much more tire clearance

consistently shocked by the amount of tire clearance every time i see one in person

Fri, 11/13/2015 - 16:42
blackholelectron
blackholelectron's picture

yeah u guys right, I think I imagine it a lot less clearance-y because I tend to ride with bros that have surlys, but there is most definitely TONS of clearance with a 440mm chainstay, could go way shorter

Quote:
if you're happily shuffling between rural corn dog purchases at 14mph, how are your needs not being met?

Fri, 11/13/2015 - 17:00
cookietruck
cookietruck's picture

coulda sworn the sotck NFE's were 435mm chainstays. remember that the NFE other than bb drop and rake was exactly the same as my davidson. hmm, gonna go look right meow.

Sat, 11/14/2015 - 20:12
lukasz
lukasz's picture

Good app to compare stack/reach between bikes?

Ok this seems p. good assuming it works:

http://www.bikegeo.net/#

Thu, 11/19/2015 - 16:40
jimmythefly
jimmythefly's picture

deadforkinglast wrote:
But honestly, I have no idea how I am going to follow through on that plan and I already have a pretty rad bike. I think I just like fucking with my bikes.

Thu, 11/19/2015 - 17:30
chazzwazzer
chazzwazzer's picture

GQ: Given two bikes with the same trail via different HTA and fork offsets, will there be any practical difference in handling? I see a lot of people complaining about track bikes with 45mm offset forks but that have similar trail figures (1-3mm diff) to bikes with less offset and steeper head tubes. I assume you might be able to feel the FC difference but otherwise steering would feel the same, yeah?

Fri, 11/20/2015 - 03:21
drwelby
drwelby's picture

The slacker of the pair will have more wheel flop.

Fri, 11/20/2015 - 09:08
axel
axel's picture

dumb question: thinking of swapping a CX fork with an axle-to-crown of 385mm in exchange for one of 400mm.
trying to raise up the front end of this frame and get better tire clearance.
(existing fork barely clears a 35mm knobby acceptably, new one will take at least 42mm)
expect that this will slacken the headtube a bit. anything else I should take into consideration that I'm missing?

fat rob.

Wed, 11/25/2015 - 00:28
rauce
rauce's picture

less bb drop, and shorter effective TT

There are simple apps mentioned above that will give you exact numbers.

Wed, 11/25/2015 - 00:46
axel
axel's picture
(Reply to #139)

rauce wrote:
less bb drop, and shorter effective TT

roger that. might put a slightly longer stem on it to deal with the shorter TT.

fat rob.

Wed, 11/25/2015 - 00:58
JUGE FREDD
JUGE FREDD's picture

there's a calculator for seeing what happens to the angles, bb drop, stack, and reach when changing fork lengths: http://bikegeo.muha.cc

but practically you're probably not going to want a slightly longer stem when you're also getting more flop and trail

It's a struggle, but you cut out his tongue, and his last words are "atmo atmo Atmo ATMO ATMOOOOOGORIHGGHRSHGGRLMGGMMGMgrrglegurglegrr....."
– akasnowmaaan

Wed, 11/25/2015 - 02:23
yummygooey

getting really close on the homercar. thoughts?

Screen Shot 2016-01-16 at 11.03.41 AM by yummygooey, on Flickr

Sat, 01/16/2016 - 14:06
ergott
ergott's picture

Send to me for proper comparison to my EP.

If someone on here did it, I'd probably like it. Since it was done by someone I don't know, they're a fucking idiot.

Sat, 01/16/2016 - 14:26
rauce
rauce's picture

650b right? Looks good to me but is the near level TT intentional for some reason? I would want more standover on a bike I was going to take off road.

Sat, 01/16/2016 - 20:35
NOVELTYNAME
NOVELTYNAME's picture
(Reply to #144)

rauce wrote:
? I would want more standover on a bike I was going to take off road.

Serious question: why?

Looks like a fop wagoneer for poopbacking. Odds are the single track will be minimal, gravel rutted roads ain't no thing.

"Folks want options!"

Sat, 01/16/2016 - 22:14
rauce
rauce's picture

Maybe this is geographical thing. Around here I'm either riding a road bike or there's a pretty good chance I'm going need to oh shit unclip.

I also think you would need more seatpost for a butt rocket bag, no?

Sat, 01/16/2016 - 22:20
yummygooey

650b, correct. Babyshoe Pass is the tire of choice, with options up to the Thunder Burts.

Near-level TT is an aesthetic thing. Standover is ~790mm with the 42mm tires, which matches a couple of my other bikes (road bike and track bike with horizontal TT).

Exposed seat post will probably be an issue for a larger butt bag. The Porcelain Rocket Charlene says it needs only 3" exposed post (http://www.porcelainrocket.com/product/small-seat-pack/). Traditional seat bag is an option too, as far as rear luggage goes.

Sun, 01/17/2016 - 01:04
oogens
oogens's picture

Level top tube with 26" wheels is kinda pursuit fixie-esque nonsense

Sun, 01/17/2016 - 12:07
crowding
crowding's picture

but portaging

Sun, 01/17/2016 - 13:37
jimmythefly
jimmythefly's picture

and frame-bagging

deadforkinglast wrote:
But honestly, I have no idea how I am going to follow through on that plan and I already have a pretty rad bike. I think I just like fucking with my bikes.

Sun, 01/17/2016 - 16:20
yummygooey

i decreased the ST length to 530mm (1* TT slope) for a smidge more seatpost exposure. fistful of seatpost "atmo".

i have a small jandd frame bag and i already know it's not going to fit in this frame. i marginally fit on my grandonneur, which had a bigger HT. will need to look at other options. low ST cage placement could open up opportunities for full length bags.

Mon, 01/18/2016 - 12:08

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