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Hi all
I have just received advice from my physio, who said i could not go wrong with my decision to buy a bike, as long as i get fitted properly. Surprise surprise. I am compelled to say thanks to all of you here for your excellent advice, as you have really hammered this message all along.

Now the question. Along the way, my physio mentioned the fit kits, computerised and otherwise, that are available in some bike stores. However, she said she could not provide much advice on them.

One close by LBS actually has one of those fit kits. However, he is more of a salesman interested in selling his expensive stuff. The two smaller LBS's whom i feel comfortable with, (because they never tried to convince me to buy a thing, recommended i go check out other shops, provided heaps of advice and asked me to come back with more questions to talk), dont appear to have one. They might but i haven't seen it.

So my question is: Is a Fit Kit necessary for a good fitting? can an experienced LBSer do it without one of those fancy looking machines? I am confident that an idiot operating this machine would get you killed on a bike. But is it necessary for proper fitting?
Thanks all again
 

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not necessary...

There was a recent post from person who got fitted with a fit kit and it came up with a ridiculously short top tube recommendation. Any decent fitter should have known something was wrong. It's more important to find a shop that can put you on the real bikes that they sell and let you ride on a trainer, while adjustment are made. If they don't offer this service, then go elsewhere.

You'd be smart to read up a bit on fitting, so you at least know the basics. Anyone can measure their own CYCLING inseam, to get a decent idea of the frame size range needed. My rule of thumb is the c-c frame size will be 30-32cm less than your cycling inseam. For example, wiht an 83cm inseam, I ride a 51cm c-c frame.

With the exception of Trek frames that have longer TTs than most brands, you won't find huge variations in the fit of frames that are the same size. Figuring out what is the same size can be the problem. A "58cm" Trek for example, only measures 54.5cm by the center to center method used by LOOK or 56cm using the center to top method. This can be confusing. Even some shop employees don't know the difference. The best way to distinguish the vertical size of the frame is by measuring the head tube length, with the headset, but NOT including spacers.

Most often, there will be two possible sizes that can be made to fit the same. A racing/performance oriented rider would select the samller and the recreational rider more likely the larger. The difference will be a 2cm shorter head tube on the smaller frame, making it possible to position the bars 8-12cm below the saddle, with a stem that's one size longer. The smaller frame will most likely have a shorter wheelbase and more weight on the front for more responsive handling.

Try www.coloradocyclist.com/bikefit for basic fit info.
 

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Many of the better e-retailers have a pretty good fit guide on the website. If you have the time and the inclination you should go thru a few of them just to see if they come up the same. Regardless you will gain some undestanding of the process and the terms.


Flyte bikes has a good one

http://www.flyte1.com/soar/janette/store/sizing.asp
 

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bull hockey

fit kit is neither
it is just bull hockey

noone or no machine can tell you how you will like the fit until you have gone over at least 100 miles on the bike - then your body will tell you

then you pick a diff stem if needed
move seat, etc
adjust to your feel

pocking right frame size to start is easy
 

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collectorvelo said:
picking right frame size to start is easy
For some people, it's not that easy.

Using C-40's method of sizing up a frame, I would be riding a 48cm - 50cm frame and I'm 6 feet tall. I think I'd be a bit cramped on that bike.

Also to get a correct length TT, I'd have to go with a 58cm - 60cm frame, but then I don't have stand over clearance and the seat angle is way to laid back.

Picking the right frame size for some people is not so easy. However, I do agree that minor adjustments need to be made after spending time in the saddle. Bike fitting is only a starting point, and should be treated as such. It should be used to find a riders basic bike dimensions to give them an idea of what bikes to look at, or in my case go custom to get in that ball park.

fouadaswad

Most bike shops that do fittings offer follow up services as part of the fitting. They put you on an adjustable bike and find out your needs for approximate ST angle, TT length, Stand over height, etc. If you fit into the relm of a manufactured bike then it's a matter of picking one with those dimensions that you like. Then they fit you to the bike once you have bought it so you have the correct saddle placement, stem length and rise, etc. If you need a custom frame they give you the dimensions, you have the builder build the bike, then they fit the bike to you once you receive it by switching out stems and such (assuming you get the parts from the shop).

Go with a shop that allows these options and you should be more than fine with the price paid and have a good fit on the bike.
 

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collectorvelo said:
fit kit is neither
it is just bull hockey

noone or no machine can tell you how you will like the fit until you have gone over at least 100 miles on the bike - then your body will tell you

then you pick a diff stem if needed
move seat, etc
adjust to your feel

pocking right frame size to start is easy
Then you don't understand fit, do you? No one ever said that a fitting provided the absolute answer to fit issues. A fitting can, however, provide a good starting point, especially if there are issues that don't resolve with futzing. You also don't understand that there's a general order to arriving at a good fit, and the first thing in that order is finding the appropriate saddle position before making other changes. You just don't move things hither and yon hoping to find something that works.

Also, without keeping track of changes and without doing things in a logical stepwise fashion, it's fairly easy to end up hurting yourself, literally.

If fitting was the cut and paste simpleton's job as you imply, then you'd think pro riders would have no need to get fittings to resolve issues or optimize performance. I guess you forgot to tell them.
 

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???

Wookiebiker said:
For some people, it's not that easy.

Using C-40's method of sizing up a frame, I would be riding a 48cm - 50cm frame and I'm 6 feet tall. I think I'd be a bit cramped on that bike.

Also to get a correct length TT, I'd have to go with a 58cm - 60cm frame, but then I don't have stand over clearance and the seat angle is way to laid back.

Picking the right frame size for some people is not so easy. However, I do agree that minor adjustments need to be made after spending time in the saddle. Bike fitting is only a starting point, and should be treated as such. It should be used to find a riders basic bike dimensions to give them an idea of what bikes to look at, or in my case go custom to get in that ball park.
Are you confusing pants inseam, with cyling inseam, which is usually 6-7cm greater? An 80cm inseam would generally yeild a saddle height of ony 69-70cm. If that's the case, then you SHOULD be on a 48-50cm c-c frame to get decent standover clearance and a normal handlebar height. If you can't make a bike that's the proper vertical size fit, then the solution is a custom. I'd really like to know how you solved this fit dilema. The TT length on stock frames only increase about 1cm for each 2cm of frame size, so it takes a lot of frame size increase to get much additional TT length. Got some frame specifics?
 

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why compare?

why compare people discussing fit on this board to Pro Riders
that is just plain silly

And this ida that you need professional help to fit yourself to a bike is just as silly

And Shops charging customers to 'FIT" them is plain insane

Look at the Road Bike Boom; how many road bikes were sold [10 million a year compared to todays few hundred thousand]
Did those buyers get 'professional fittings'
Did those riders enjoy their bikes?
Did those riders all have awful pain from poor fitting bikes?

Get serious; bike fit is easy, now comedy that is hard
 

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C-40 said:
Are you confusing pants inseam, with cyling inseam, which is usually 6-7cm greater? An 80cm inseam would generally yeild a saddle height of ony 69-70cm. If that's the case, then you SHOULD be on a 48-50cm c-c frame to get decent standover clearance and a normal handlebar height. If you can't make a bike that's the proper vertical size fit, then the solution is a custom. I'd really like to know how you solved this fit dilema. The TT length on stock frames only increase about 1cm for each 2cm of frame size, so it takes a lot of frame size increase to get much additional TT length. Got some frame specifics?

Well, I suppose it depends on what you are considering inseam. From floor to crotch (no shoes) I have an 80.1 cm inseam and am 6 feet tall. I do somewhat resemble a Gorilla.

I'm currently riding a sloping top tube 56cm frame that's just too small for me, but gives me the longest TT length while still letting me straddle the frame.

I put in my order for a custom Curtlo a couple of weeks ago, which means it should be here sometime in April or early May. The dimensions I placed for that bike, which I'll go over with Doug when it's my turn are:

-74.5 degree seat angle (short femurs to boot)
-58 cm top tube, may go to a 59 depending on his recomendation (most fitting tools put me in the 58-60 range)
-15.5 cm Head Tube
-Seat tube is to be determined as I'm looking for a 10 degree slope from the head tube.

Going to a 74.5 degree seat angle and a 58 cm TT will effectivly give me 3 cm more TT length compared to my current bike (56 cm/73.5 degree seat angle). My actual seat tube will likely be around 47cm to 48 cm.
 

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cycling inseam...

Cycling inseam is just as it shows at the website I linked. I've never seen it measured any other way.

www.coloradocyclist.com/bikefit

Floor to saddle-like crotch contact in bare feet. Having saddle-like crotch contact is vital. I like to use a bike wiht a horizontal TT and block up the wheels until I get firm contact, then measure from the floor to the top of the TT.

I have two comments, the head tube is tall for the saddle height (is it really only 69-70cm?). You must want a small saddle to bar height diffrence. With a 72cm saddle height, I'd use 135mm with an 80 degree (-10) stem and no spacers.

One thing often overlooked on custom frames is weight balance. It's fine to use a long TT, as needed, but I wouldn't make it any longer than needed for a 120 or 130 stem, otherwise you may find that the front end is light.
 

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C-40 said:
Cycling inseam is just as it shows at the website I linked. I've never seen it measured any other way.

www.coloradocyclist.com/bikefit

Floor to saddle-like crotch contact in bare feet. Having saddle-like crotch contact is vital. I like to use a bike wiht a horizontal TT and block up the wheels until I get firm contact, then measure from the floor to the top of the TT.

I have two comments, the head tube is tall for the saddle height (is it really only 69-70cm?). You must want a small saddle to bar height diffrence. With a 72cm saddle height, I'd use 135mm with an 80 degree (-10) stem and no spacers.

One thing often overlooked on custom frames is weight balance. It's fine to use a long TT, as needed, but I wouldn't make it any longer than needed for a 120 or 130 stem, otherwise you may find that the front end is light.

Actually the headtube will equate to about what I have on my current 56cm frame. The current frame has a 16cm integrated headset head tube. Curtlo uses a tradational HT and headset. Should provide a pretty similar bar height.

The top of my bar is about 7.5 cm below the top of my saddle. I'd actually like it to be a little lower than it is, flexiblity isn't an issue with me.

I don't like long stems due to my size. I'm currently running about 265 pounds and a good competition weight for me is 220-225 (that's what I used to race sport class at and finished top 5 for the state XC series a few years back). I would prefer to limit flex in the bike, especially in the front of the bike.

My saddle height is actually somewhere in the mid-upper 80cm range, not in the 69cm-70cm range you are thinking. My pedal stroke is toe down (not heal down) and I use my calves a lot in the pedal stroke. Also, I have my seat a fair amount forward compared to most people, which brings the seat higher than normal also. The front of my seat is actually just in front of the bottom bracket. What works for me, won't necessarily work for others. I have big quads, big claves and almost no glutes. I generate a lot of power through my legs, not my butt like other cyclists do.

I'm only slightly concerned about the long front end of the bike. However, with my long body, long arms and heavier weight it shouldn't be much of an issue in the end.

I however am a perfect example of somebody that needs a custom frame. Normal bike frames just don't fit me correctly.

The reality is my wife would also be a perfect candidate for a custom frame if she actually rode her bike a lot. She has a 72.4cm inseam and is 4'11" tall. She has very long femurs and needs a laid back seat angle. Small bikes have shallow seat angles which makes her move her saddle all the way back on the seat post. Basically we are complete opposites, funny how that works...
 

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your figures make no sense...

First you say your inseam is only 80cm, now you say your saddle height is in the mid to upper 80cm range. This makes no sense at all. Saddle height (crank center to top of saddle) is typically 10-11cm less than inseam.

If you meant that your inseam was in the mid to upper 80cm range, then it's not so short at all.

I'm all for giving out advice to others, but it seems like you're not up the standard nomenclature.
 

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C-40 said:
First you say your inseam is only 80cm, now you say your saddle height is in the mid to upper 80cm range. This makes no sense at all. Saddle height (crank center to top of saddle) is typically 10-11cm less than inseam.

If you meant that your inseam was in the mid to upper 80cm range, then it's not so short at all.

I'm all for giving out advice to others, but it seems like you're not up the standard nomenclature.

Then it would seem you don't know much about pedal strokes. I totally disagree that somebody's pedal stroke should be 10-11 cm less than their inseam? Somebody that has a heal down pedal stroke (i.e. heal lower than the toe at the bottom of the pedal stroke) and sits a ways behind the bottom bracket, yea, I could see that. As I said in a previous post, I pedal toe down (i.e. the heal is higher than the ball of my feet at the bottom of my pedal stroke), which extends my inseam length in the saddle. I also have my saddle positioned so the middle off the saddle in only about 14cm behind the bottom bracket (I have a 0 degree post with the saddle forward) and the front of the saddle is actually in front of the bottom bracket (looking vertically). That's what it takes to get my knee just slightly in front of the pedal spindle. I don't adhear to the knee behind the pedal for my body since I lose power and my RPM's drop dramatically by going back in the saddle.

Why I'm explaining this to you at this point is beyond me. I know what I need and trying to explain it to you over the internet at this point seems to be fruitless.

I'm all for giving out advice to others, but it seems like you're not up the standard nomenclature
As far as this statemet goes, it's totally false. I've been involved in cycling for approximately 12 years both on mountain bikes and road bikes. I've been a recreational rider to a serious racer and go in and out of racing depending on my time schedule. I'm very well read and very well versed when it comes to cycling and it's nomenclature.

Years ago when I had time to spend on the net I was actually quite well known for my cycling knowledge on mtbr.com (the sister site of roadbikereview.com) though it was under a different name.

My rule of thumb is the c-c frame size will be 30-32cm less than your cycling inseam. For example, wiht an 83cm inseam, I ride a 51cm c-c frame.
Personally, this statement makes me wonder a bit about your knowledge when it comes to bike fit. That's an extreemly generalized method of bike fitting and would put the "Joe Average" build in the ball park. It however does little for those individuals on the fringe and the needs that they might have when it comes to bike fit.

My original post was a reply to collectorvelo stating that fitting a bike is not as simple as it seems. Not everybody fits mass manufactured frames very well. You asked for specifics towards the frame that I'm having built, I supplied them and you end up telling me I'm not up to the standard nomenclature? What's that about? Telling somebody you have never met, had about a 2 minute conversation with and knows pretty much exactly what they need size wise that they basically don't know what they are talking about?

OK then....
 

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Disagree-

C-40 said:
The best way to distinguish the vertical size of the frame is by measuring the head tube length, with the headset, but NOT including spacers.

Most often, there will be two possible sizes that can be made to fit the same. A racing/performance oriented rider would select the samller and the recreational rider more likely the larger. The difference will be a 2cm shorter head tube on the smaller frame, making it possible to position the bars 8-12cm below the saddle, with a stem that's one size longer. The smaller frame will most likely have a shorter wheelbase and more weight on the front for more responsive handling.
.
My racer friend says that is one of the worst ways to determine fit-
says you can get plenty of spacers/extenders and various rises of stems to fit a bike regardless of head tube length -
Just look at the cannoday sp? with the headshock inside suspension fork - internal?
anyway he says those have giganticly long headtubes but have a reverse rise stem

plus - look at all the guys posting pics of really tall steerer tubes with tons of spacers and then a flat stem...

anywho - he says that figure sizing based on the effective top tube length center to center - cause that determines to the largest extent the weight distribution /comfort / fit
all other factors like seat height/position and handlebar height/postion can be changed to fine tune

This makes logical sense to me as you want to size based on the most immutable / unchangeable and most common factor and work outwards from there

basically it is simple - find the most constant variable
 

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Dont' get offended...

I think you've failed to read my post thoroughly. Saddle height is most commonly measure from the center of the crank to the top of the saddle, as I noted in my post. Pedal stroke is NOT the same thing, (nomenclature again). Obviously, pedal stroke is going to be longer by about 16-17cm (crank length) depending on exactly how you measure it (to center of pedal spindle or top of pedal platform).

My inseam is 83cm, but my pedal stroke is about 89cm, and saddle height is 72cm. Get the difference?
 

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silly argument...

We're talking road bikes here, usually higher end models. 99% have a fork length of 367to 374mm, a very narrow range.

Spacers are very limited, to 3cm maximum on most carbon steerers. Stem rise can be used to cover about a 5cm range, but most serious riders (certainly racers) wouldn't be caught using a big stack of spacers and a high rise stem.

As I stated in my other posts, TT length only changes about half as much as the frame size and head tube length. BOTH should be in the correct range is you want a decent looking setup. The problem that gets posted often on this site is someone completely ignoring the head tube length and buying what they think is the proper TT length. Then they can't get the bars up to the desired height without a 100 degree stem and 3cm of spacer or just the opposite, they can barely straddle the bike.

See if your friend is smart enough to know how the seat tube angle affects the reach of a frame. Which frame has the most reach, a 54cm TT with a 72.5 STA or a 52.5cm TT with a 74.5 STA?
 

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C-40 said:
I think you've failed to read my post thoroughly. Saddle height is most commonly measure from the center of the crank to the top of the saddle, as I noted in my post. Pedal stroke is NOT the same thing, (nomenclature again). Obviously, pedal stroke is going to be longer by about 16-17cm (crank length) depending on exactly how you measure it (to center of pedal spindle or top of pedal platform).

My inseam is 83cm, but my pedal stroke is about 89cm, and saddle height is 72cm. Get the difference?
Sounds like we have different ideas of saddle height. Honestly, in my 12 years of riding I rarely ever hear of people measuring their seat height that way. From time to time yes, but not often.

With that measurement my saddle height is only 72 cm.
 

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a man goes into the bar...

collectorvelo said:
why compare people discussing fit on this board to Pro Riders
that is just plain silly

And this ida that you need professional help to fit yourself to a bike is just as silly

And Shops charging customers to 'FIT" them is plain insane

Look at the Road Bike Boom; how many road bikes were sold [10 million a year compared to todays few hundred thousand]
Did those buyers get 'professional fittings'
Did those riders enjoy their bikes?
Did those riders all have awful pain from poor fitting bikes?

Get serious; bike fit is easy, now comedy that is hard
Actually - comedy is pretty easy - just google "how to write jokes" and you'll see

Now - thinking logically - you are over simplifying figures without looking closer
In those days- the bad old days I believe from my research - there were:
1) no mountain bikes
2) no comfort bikes (some guy "invented" them in the late 80's I have been told...)
3) no lowrider bikes... well you get the gist - there were MOSTLY/ONLY road bikes being sold

I should ask the next logical questions to your questions:
1) how many of those riders actually rode those bikes much more than extremely casually
2) how many of those riders got racked when they slipped off their too low seats onto the too high top tube?
3) how many of those racked riders were not able to reproduce and thus through natural selection - allow those un-racked riders to procreate and further the genetic line of cyclists who believed riding slightly less painful, smaller and better fitting bikes just - well - felt better...
;)

oh yeah- last question -

4) how many of those "bike boom" riders were so stoned they couldn't tell if someone smacked them in the groin with a 2x4...

POW....uuuuh duuuuude what was that...?....puff..puff...


(come on - you know who/whom I'm talking about...)

see - comedy is not so hard
telling jokes on stage in the summer while wearing a black leather thong after popping ****** -
now THAT'S Hard...



But- I agree - the fees shops charge for "fit" is a bit high

but according to my racer friend- who is far too busy riding his bike 6 hours a day to post on this board sez:

the good ones that KNOW what they are doing are worth paying IF you ride a great deal and or care a great deal - ie - they adjust all aspects of the bike- cleat position, seat, stem rise reach angle (this an actually save you money - not to mention possible excercise induced over-use injuries)

One of my racer friends buddies adjusted his cleat position he had ridden on for hundreds of miles thinking he would "fix" something and wound up with a muscle pull after a couple of rides - definitely due to that changed cleat position

I look at fit kits
Kind of like some people would rather go to Ruth Chris to buy a steak for $50 when they could cook one just as well for $10 at home

well- that IS oversimplified but it makes things much - well - simpler
;)
 

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collectorvelo said:
Look at the Road Bike Boom; how many road bikes were sold [10 million a year compared to todays few hundred thousand]
Did those buyers get 'professional fittings'
Did those riders enjoy their bikes?
Did those riders all have awful pain from poor fitting bikes?
Maybe that's why the "Boom" went bust.

Fit matters allot more at mile 30 than it did at mile 3.
 

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Wookiebiker said:
Sounds like we have different ideas of saddle height. Honestly, in my 12 years of riding I rarely ever hear of people measuring their seat height that way. From time to time yes, but not often.

With that measurement my saddle height is only 72 cm.
What? I've only been involved with cycling a couple of years and I've never heard it referred to as anything else.

Google Saddle Height and see if you can find it defined another way.
 
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