critique my position? pics inside

[adam_mac84]

I am currently borrowing a bike to ride whenever the weather permits. it is a 61cm. I am 6' 3". Due to finances i am purchasing online and trying to iron out my 'fit' before i purchase. I will swap parts as necessary and tweak my fit as i am able as my riding improves... but i seek the knowledge base of this forum to assist me in a few tips.

i currently dropped the seat ~1.5-2cm and it feels pretty good. I am thinking of shortening stem from 110 to 100mm (i took my wife's 100mm 16* and it felt pretty good.) current stem is 110 6*

[LongIslandTom]

I am currently borrowing a bike to ride whenever the weather permits. it is a 61cm. I am 6' 3". Due to finances i am purchasing online and trying to iron out my 'fit' before i purchase. I will swap parts as necessary and tweak my fit as i am able as my riding improves... but i seek the knowledge base of this forum to assist me in a few tips.

i currently dropped the seat ~1.5-2cm and it feels pretty good. I am thinking of shortening stem from 110 to 100mm (i took my wife's 100mm 16* and it felt pretty good.) current stem is 110 6*

At the bottom of the pedaling stroke, usually a 30-degree-from-vertical bend in your knee is considered optimum for efficient pedaling. I think that seat is set a bit too low (your knee looks like it's at a 50 degree angle so it's probably not giving you good extension).

The top tube length also looks a bit short for someone your size, considering how far back you seem to be sitting.
Just my $0.02..

[adam_mac84]

thanks Tom for your thoughts. I agree with what you have stated. It's amazing to me that i may need to go up a size (to 63cm in this particular setup), when LBS were putting me on 58's and 57's. (i assume it's because, as they told me... this is the biggest bike we carry).

I have been reading nearly everything i can find on bicycle fit, including many sports med medial journals etc.

[stapfam]

That saddle needs to go up----Unless you start finding knee pain coming in. Will probably cost a longer seat post and if that is the case- Then get one with a bit more layback. But then you may find the bars a bit too low so they would have to be raised aswell.

Would not be cheaper- but I would find a different shop that will supply a better fitting bike . But before you buy next time- get a test ride .

[10 Wheels]

Raise the seat. Top Tube is OK, just tilt the handle bars down more.

[10 Wheels]

This guy has a good fit.

[adam_mac84]

. But before you buy next time- get a test ride .

i am test riding this bike... it is borrowed from my dad who has hurt his knee... sort of an extended ride so that I can get all of these types of things ironed out.

[iforgotmename]

In my opinion buying online is not always cheaper. In the long run having a good lbs is very important. My old lbs (they closed ) was very helpful. The mechanic was very good about helping me with my budget. I told him in advance of what I wanted to spend and the quality/durability I was looking for. He saved me money getting me good components and steering me away from expensive "weight" saving components. Not to mention the free installs ,service and advice I received. Maybe get a bike that you can build on in the future...good service is important. Just my opinion. Browse globally-buy locally and don't forget about year end clearances.

[The Human Car]

My 2 cents besides the seat going up consider moving it forward as well.

[coldfeet]

In my opinion buying online is not always cheaper. In the long run having a good lbs is very important. My old lbs (they closed ) was very helpful. The mechanic was very good about helping me with my budget. I told him in advance of what I wanted to spend and the quality/durability I was looking for. He saved me money getting me good components and steering me away from expensive "weight" saving components. Not to mention the free installs ,service and advice I received. Maybe get a bike that you can build on in the future...good service is important. Just my opinion. Browse globally-buy locally and don't forget about year end clearances.

I agree, mostly, but if the local store is trying to sell him 57-58 cm bikes, because thats all they have, don't think they qualify as that good a store. Don't forget you will need some fairly strong wheels too.

[iforgotmename]

I agree, mostly, but if the local store is trying to sell him 57-58 cm bikes, because thats all they have, don't think they qualify as that good a store. Don't forget you will need some fairly strong wheels too.

Agreed, but there is usually more than one local shop in the area. I have "box store" shops also but I found a good one and will travel across town. But that's just me.

[adam_mac84]

I don't disagree with you guys regarding buying at an LBS (best LBS price i have seen on most bikes is the 8-900 range, and i can get used/online for 1/2 that)... i also plan on doing my own wrenching because i had to sell both of the trucks that i used to build on in my spare time when i got married... I figure if i can do a motor swap on a vehicle and set up gears in a differential that spins nearly 1000 rpm's at times, i should be able to figure out a bike (also got zinn's book for xmas)

there are a few more LBS in town that i will be visiting when i am more sure of what i want to get onto...

i rode 10 miles today (decent ride for me as i work my endurance up), seat definately needs to go up. I find that i sit really far back on the actual seat, so i am going to have to play around with where i am on the seat vs where the seat is positioned in relation to me... most pictures i see online people seem pretty far forward on the actual saddle.

thanks for the replies... i will probably make some adjustments tomorrow and take it for another spin, and snap an 'updated' pic if anyone is interested in

[LongIslandTom]

i rode 10 miles today (decent ride for me as i work my endurance up), seat definately needs to go up. I find that i sit really far back on the actual seat, so i am going to have to play around with where i am on the seat vs where the seat is positioned in relation to me... most pictures i see online people seem pretty far forward on the actual saddle.

Yep, that is exactly why I think you needed a frame with a longer top tube. In your photo, it almost looked like you are about to slip off the back of that saddle.

As a matter of fact, I'm a bit surprised you haven't experienced any discomfort.. For a saddle to fit properly, it has to support the two bony bumps (the ischial tuberosities of your pelvic bone, aka your "sit bones") on the inside of your glutes. If you are sitting that far back, I can't see how it can give your sit bones any support.

You definitely need a frame with a longer top tube than that one in your original photo.

Is this the bike in your photo? http://www.motobecane.com/MBUSAfcx.html

If it is, it looks like the biggest frame they got has a 610mm top tube (64cm seat tube). Which size is the bike in your photo?

If you need one bigger than that, this Motobecane has a 630mm top tube in its largest size: http://www.motobecane.com/MBUSAmsp.html

[adam_mac84]

yes, that is a 61cm motobecane... i do put my ish tub's on the seat... just basically on the very back piece of the seat... bones on the very back of the seat with the rest of my arse hanging off the back. My big old butt must be swallowing that poor seat. for instance, this guy:



i guess its more getting the seat on the medial border of my ish tube's versus sitting right on top of em

I re-did my competative cyclist fit calculator measurements and am going to try to simulate that on my 61cm borrowed bike...

it's crazy that i may be looking at a 63cm... just seems so big, and impossible to see any in person at my LBS, because even the one a few miles away who told me... you shouldn't even be looking at bikes without a 6 as the first number (after telling him i was sized to a 58 giant frame), only had 1 XXL specialized road frame.

am i going to be moving into custom size bikes at this point? i can't be the tallest biker out there

[adam_mac84]

here is my french fit from competative cyclist... now, i realize this is not necessarily the golden ticket, hence why i am posting here, and am trying to get some saddle time and tweak the fit before i commit to any particular brand/frame

The French Fit (cm)
-------------------------------------------
Seat tube range c-c: 60.7 - 61.2
Seat tube range c-t: 62.5 - 63.0
Top tube length: 57.9 - 58.3
Stem Length: 11.3 - 11.9
BB-Saddle Position: 74.0 - 76.0
Saddle-Handlebar: 60.0 - 60.6

this suggests that i should be able to make it work with the 61cm bike i am currently borrowing

[adam_mac84]

Here is an updated pic. I am going to try to ride 5-10 tomorrow to see how it feels. Flipped the stem, and raised the seat tube about 2-2.5cm. I still think that my seat could go back a tad because when i move forward on the saddle, i feel so cramped (also going up with the stem another cm or 2 will effectively push the seat 'back'). We will wait and see




assuming bike fitters measure knee flexion the same way I do in physical therapy (greater troch. through joint line to lat malleolus) then it's still nearly 50* of knee flexion Hard to imagine going up another 3-4cm in seat height... its quite a reach to the ground as it is Any other tips to get more knee extension besides going up with the seat?

[LongIslandTom]

Here is an updated pic. I am going to try to ride 5-10 tomorrow to see how it feels. Flipped the stem, and raised the seat tube about 2-2.5cm. I still think that my seat could go back a tad because when i move forward on the saddle, i feel so cramped (also going up with the stem another cm or 2 will effectively push the seat 'back'). We will wait and see

assuming bike fitters measure knee flexion the same way I do in physical therapy (greater troch. through joint line to lat malleolus) then it's still nearly 50* of knee flexion Hard to imagine going up another 3-4cm in seat height... its quite a reach to the ground as it is Any other tips to get more knee extension besides going up with the seat?

The new photo with your left leg at the bottom of the pedal stroke looks like you are almost there with the leg extension. Remember that even 1/8 of an inch in seat height can make a world of difference, so this is what I would suggest:

Bring a multitool with you when you ride, so you can make on-the-spot adjustments to your seat height. Try different heights in 1/8" increments until you find that 30-degree knee-bend sweet spot where your knees aren't feeling sore after a mile-- This is the realm of fine-tuning your seat height. Oh, and at the proper height, you are NOT supposed to be able to put your feet flat on the ground when sitting on the saddle.

As far as you feeling cramped when you try to sit a bit more forward on the saddle so it doesn't feel like you are about to fall off the back of the seat, that's just another sign that you need a frame with a longer top tube (especially if your seat is already slid back as far as it will go on its mounting rails).

My additional $0.02.

[stapfam]

I ride several frames that cover a wide range of frame sizes. Admittedly Compact frames that do cover those sizes- but I can fit frames that cover from 46Cms to 54. Seems a lot of size difference but a frame that is "Just" a bit too small can be made to fit with a longer seat post and a longer stem. Don't fully recommend it but it can be done.

The Black OCR is an Extra Small in Giant sizing. Covers from 46 to 51. The TCR is a small that covers from 49 to 54. And I also ride a medium that covers from 52 to 59.

As you can see- the OCR has a long seat post and a longer stem The TCR still has standard seat post and stem fitted. Both bikes fit with no problems.

[LarDasse74]

The latest pic looks like you are on the right track. I would still reccomend raising the seat slightly.

Generally, you should use the seal fore-aft position to adjust for your legs and your stem rise/reach to adjust for your back and arms - it is often looked at as a mistake to use saddle adjustments to compensate for reach issues.

All that being said, the reach looks pretty good to me, but there is no right or wrong - whatever makes you most comfortable is what you need to do.

As for your concerns about bike sizes - when you walk into a room are you often the tallest one there? What about when you walk into a bike shop? If someone 6'3" should not be on an XL or XXL, who should? Some people prefer a smaller bike, but I believe this is because they have always riddent bikes that are too small and that is what they are used to. Most tall people prefer a bike that fits.

Have you measured your pubic bone height? THis is the basis for most fit systems and will get you in the ballpark for frame size.

Here is an excellent article on the Rivendell website:

http://www.rivbike.com/article/bike_...g_a_frame_size

Keep in mind the sizes mentioned are level-top-tube (traditional) road bike sizes, which tend to correspond to sloping-top-tube frame sizes about 2 or 4 cm less.

[adam_mac84]

well, moved the seat up about 1.5-2 more cm. WOW, what a difference. Between that and the stem flip things are really starting to feel better.

I do notice that my triceps are really working while i am riding, and as i move back on the seat or move my hands out past the brifter position, things generally feel more comfortable...

i guess the next step is trying a different seat post (to allow more offset back) versus a longer stem. I am going to have to research the implications of having seat setback too far behind BB. Right now i am near at least 10cm seat setback (nose of saddle to bottom bracket)

better area to make up room? Seat back vs longer stem?

it's really lookin like i will need a 63cm frame (at least if i go w/ this frame) to make sure i have a long enough TT

this was reinforced by the fact that my seat was as far back as it'll go and my knees still hit my elbows if i am in the drops

[LongIslandTom]

Having the seat set too far back behind the bottom bracket will have adverse effects on handling and ride quality-- You will have almost all your weight over the rear wheel.

Definitely need a longer top tube length!