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Re: Unusual bike fit problem

Posted: Sun Sep 09, 2012 5:12 am
by PawPaw
Neil I've never seen hip extension limited by monoarticular G.Max. What are your hams like? Can you get 90 degrees hip extension in supine with support under lumbar spine.

You have attributed your 'back spasm' to a big knot in your gluts. Explain your reasoning for a g.max issue causing back spasm. Which muscles are spasming and at what vertebral levels, and on which side/s? I'll stick with your back spasm being due to discal or spinal stenosis.

I don't agree G.max/med or their fascia could impact the sciatic nerve, even with congenital variation - review their anatomical relationship. TLL, you might think one muscle was the cause of all your months of suffering, but that is highly unlikely - more likely you had a disc issue that gradually settled, but was the original cause of a muscle getting dysfunctional.

Neil, how long are you sustaining the slump test for? How long are the rides that result in back spasm and how long til spasm?

How long can you hold the plank for? and do you get back pain with it? Zep, planks help unmask disc issues.

Re your knee and toe alignment, TTers tend to tib tube over toes, roadies over pedal axle.
If you had a good bike fit, you'd be aware of your knee and back angles, which are?

As for standard of MS physios, yes there's great variance in quality of ax, but there's greater variance in the consistency and clarity clients describe symptoms.
Many less straight forward conditions would require several one on one hour long appointments, and a patient who complies with advice given. ha. FUrther, clients tend to shop around, and lots of chronic conditions tend to resolve over time. whoever is treating at the time of resolution gets the kudos.

Re: Unusual bike fit problem

Posted: Sun Sep 09, 2012 5:42 am
by toolonglegs
PawPaw wrote: TLL, you might think one muscle was the cause of all your months of suffering, but that is highly unlikely - more likely you had a disc issue that gradually settled, but was the original cause of a muscle getting dysfunctional.
Yes I had a nerve issue in my back caused by a muscle problem... one problem turned into many. But the root cause was always the same.

Re: Unusual bike fit problem

Posted: Sun Sep 09, 2012 6:50 am
by twizzle
ZepinAtor wrote:
A 100mm drop sounds excessive. If you already have your stem angled up & a large stack height then I would guess your frame is way too small.
Why? Do you know how long his arms are?



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Re: Unusual bike fit problem

Posted: Sun Sep 09, 2012 8:34 am
by ZepinAtor
twizzle wrote:
ZepinAtor wrote:
A 100mm drop sounds excessive. If you already have your stem angled up & a large stack height then I would guess your frame is way too small.
Why? Do you know how long his arms are?
I have no idea how long his arms are, but reading back through his comments alerts me to the fact that he has long legs & for some strange reason is trying to shove his seat very forward ? He has also stated that his stem is angled up & has a comparatively lower position than all of his mates.A short femur would "generally" have you wanting your seat forward & he has stated his legs are long for his height. All of my comments are generalisations going on the information presented to me by the OP.

I would like to see a side on photo on a trainer pedalling under moderate force before I cast any more opinions into this somewhat mystifying thread.

Re: Unusual bike fit problem

Posted: Sun Sep 09, 2012 10:09 am
by Marty Moose
[/quote]



I would like to see a side on photo on a trainer pedalling under moderate force before I cast any more opinions into this somewhat mystifying thread.[/quote]
Now that's the best post here give us some pics.
I had a "computer fit" nice man good for ball parking your bike but he was not able to fix me knee issues in fact his set up have me quadriceps tendonitis now I've back to what I know and ex national riders input.
The cause ended up being the pedal axle on my Ultregra spd sl having 5mm lateral movement computer didn't pick this I did $240 for nothing. The computer fit "retul" does have its place but its not the final word.
Far as knee over your toes It'd be doing some of my own set back research. Sounds to me like you are to far forward of the bottom bracket.Read Steve Hogg's stuff as recommended, pay for for his pdf's they are a good read.



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Re: Unusual bike fit problem

Posted: Sun Sep 09, 2012 11:22 am
by NeillS
Thanks for the input everyone. Trying to diagnose a complicated biomechanical problem over the internet is completely useless so I won't try too hard in that regard. Also not going to enter a pissing contest over clinical skills. I specialise in running biomechanics so bike mechanics are a bit foreign to me.

The points about the computer fit are good actually, the guy didn't make mention of my long inseam measurement because he didn't measure it - we simply put the IR markers on my legs and went to the bike straight off. He did make mention of my ridiculously flexible ankles and excellent hip range which I already knew about.

I just realised I forgot to mention the frame size on my bike - it's got a 51.5cm top tube centre to centre, and the measurement from the top of the seat to the centre of the bottom bracket is currently 78cm as far as I can measure. Do these sound about right for a 175cm bloke with a 90cm inseam or way off? The cranks are 172.5mm by the way.

Last question - who can recommend a good human bike fit in inner melbourne? It will be interesting to see what they come up with versus what the machine told me!

Re: Unusual bike fit problem

Posted: Sun Sep 09, 2012 11:26 am
by NeillS
Oh and I will try to borrow my friend's mag trainer next week and set up the camera to have a look at my setup side-on, and we can compare the two sides to see if they're symmetrical. Should be an interesting comparison!

I just measured my femur length as accurately as I could (not easy to do by yourself) and they are the same as far as I can tell. I have always felt "off" on the bike, like one leg is working harder than the other, but have never been able to figure out where it's coming from, and my hips are dead steady when I cycle so it's a bit of a mystery. I've even done side-to-side power testing with split lunges and single leg squats and can't find any major difference - if anything my bad leg has sometimes been slightly stronger than my good one. Weird.

Re: Unusual bike fit problem

Posted: Sun Sep 09, 2012 11:45 am
by PawPaw
toolonglegs wrote:
PawPaw wrote: TLL, you might think one muscle was the cause of all your months of suffering, but that is highly unlikely - more likely you had a disc issue that gradually settled, but was the original cause of a muscle getting dysfunctional.
Yes I had a nerve issue in my back caused by a muscle problem... one problem turned into many. But the root cause was always the same.
TLL, I forget what muscle was the cause of your back pain and nerve problem....what were you told again, and what therapy fixed the problem?

Neil, thanks for clarifying where you're coming from.

Re: Unusual bike fit problem

Posted: Sun Sep 09, 2012 11:54 am
by gabrielle260
If you are a cycling tragic like me and can't resolve a bike fit problem, I recommend consulting Steve Hogg in Sydney. He is recognized globally as an expert in fit issues. You can send him a question via cycling news fitness forum or email him. Or you can do what I did and drive up (from Melb for me) because I think it is worth it!
I will post about it more in the 10k thread as part of my cycling holiday.
Good luck sorting out your problem!
Andrew

Re: Unusual bike fit problem

Posted: Sun Sep 09, 2012 12:26 pm
by NeillS
Okay so I just plugged in my numbers to the competitive cyclist thingo and got this;

Image

Now my top tube length is 51.5 or 52cm if you measure centre to centre horizontal to the ground. BB-Saddle position recommended is around 82cm, mine is about 79cm..... top tube length is perhaps the most important and even that is telling me I need a bigger frame. What do you guys reckon?

Re: Unusual bike fit problem

Posted: Sun Sep 09, 2012 3:02 pm
by vander
NeillS wrote:Thanks for the input everyone. Trying to diagnose a complicated biomechanical problem over the internet is completely useless so I won't try too hard in that regard. Also not going to enter a pissing contest over clinical skills.

I just realised I forgot to mention the frame size on my bike - it's got a 51.5cm top tube centre to centre, and the measurement from the top of the seat to the centre of the bottom bracket is currently 78cm as far as I can measure. Do these sound about right for a 175cm bloke with a 90cm inseam or way off? The cranks are 172.5mm by the way.
Too small I would say, what is your stem length (also important) you should have a slightly bigger bike but a small stem, I think. Im 181cm with 86cm inseam (so longer up top) and I am on a much bigger frame. I think you should be more around the 53-54cm option. 172.5 cranks should be fine.

I also want to know how long the rides are before you start getting pain? Not just how long but what type what the week/month was like before that (including things other the cycling)? How long are you waiting till you go back to riding? What was your training like before? Any changes in shoes, saddle etc?

(AT) Paw Paw: I dont believe in plank as a clinical measure for core strength it is not very effective. Also saying disc or spinal stenosis is jumping to conclusions a bit. However I agree a g. max issue is very unlikely to cause back spasm.

(AT) Scott: Cheers :oops: :)

Re: Unusual bike fit problem

Posted: Sun Sep 09, 2012 3:07 pm
by twizzle
NeillS wrote:Okay so I just plugged in my numbers to the competitive cyclist thingo and got this;

Image

Now my top tube length is 51.5 or 52cm if you measure centre to centre horizontal to the ground. BB-Saddle position recommended is around 82cm, mine is about 79cm..... top tube length is perhaps the most important and even that is telling me I need a bigger frame. What do you guys reckon?
No can see piccy, same issue as missing pic in first post? I use photobucket.


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Re: Unusual bike fit problem

Posted: Sun Sep 09, 2012 3:16 pm
by twizzle
ZepinAtor wrote:
twizzle wrote:
ZepinAtor wrote:
A 100mm drop sounds excessive. If you already have your stem angled up & a large stack height then I would guess your frame is way too small.
Why? Do you know how long his arms are?
I have no idea how long his arms are, but reading back through his comments alerts me to the fact that he has long legs & for some strange reason is trying to shove his seat very forward ? He has also stated that his stem is angled up & has a comparatively lower position than all of his mates.A short femur would "generally" have you wanting your seat forward & he has stated his legs are long for his height. All of my comments are generalisations going on the information presented to me by the OP.

I would like to see a side on photo on a trainer pedalling under moderate force before I cast any more opinions into this somewhat mystifying thread.
Small frames have slacker seat tube angle than big frames, it's bloody hard to get the seat far enough forwards when you have stacks of seat post. This also effectively shortens the TT length... and on and on. I ride ~7cm setback on a 'medium' TCR, with a flipped seat post and an inverted 110mm stem. And my drop is about 11cm...

He's an outlier, which is why I was interested in seeing the CC fit numbers, and like the OP, I get back pain if my saddle is further back... which is where I had it when Steve had a look back in Jan.


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Re: Unusual bike fit problem

Posted: Sun Sep 09, 2012 3:50 pm
by NeillS
These are the pics, sorry if you couldn't see them before - i was hotlinking from another site.

Bike setup;

Image


Bike fit stats;

Image

Re: Unusual bike fit problem

Posted: Sun Sep 09, 2012 4:22 pm
by ZepinAtor
Wow, those are some challenging measurements. Very long inseam for somebody 174cm. You're built like a Giraffe with a short neck. I'm the complete opposite with an inseam of 85cm & 187cm tall. I ride a 58cm compact with a 115mm stem. Saddle height is 754mm from c of BB to top of saddle. (920mm from top of pedal).

Not sure if I'm seeing this right as camera angle could be dictating your saddle pointing down at the front. Sorry, but that bike looks all wrong from where I sit. Looks like somebody 6"3' has borrowed their mates 52cm bike. Then again I can't see you so who knows.

As Twizzle has stated with heaps of post showing bringing the saddle forward to accommodate the crank/knee/foot positioning is challenging.

A 54cm frame would have less post protruding, but then put your bars further out & higher. Perhaps with a 70mm stem this would work ? I'm taking stabs in the dark here & only passing on my opinions. 27 years cycling & 4 Retul bike fits does not make me an expert by any means.

I would repeat my coach's sentiments on here regards bike fits, but this is a family based audience which would not appreciate his views.

Re: Unusual bike fit problem

Posted: Sun Sep 09, 2012 4:34 pm
by vander
ZepinAtor wrote:Wow, those are some challenging measurements. Very long inseam for somebody 174cm.

Not sure if I'm seeing this right as camera angle could be dictating your saddle pointing down at the front. Sorry, but that bike looks all wrong from where I sit. Looks like somebody 6"3' has borrowed their mates 52cm bike. Then again I can't see you so who knows.

As Twizzle has stated with heaps of post showing bringing the saddle forward to accommodate the crank/knee/foot positioning is challenging.

A 54cm frame would have less post protruding, but then put your bars further out & higher. Perhaps with a 70mm stem this would work ? I'm taking stabs in the dark here & only passing on my opinions. 27 years cycling & 4 Retul bike fits does not make me an expert by any means.

I would repeat my coach's sentiments on here regards bike fits, but this is a family based audience which would not appreciate his views.
I think based on the measurement by Competitive cyclist he may even get away with a 55-56cm frame with a 90 or so mm stem.

Re: Unusual bike fit problem

Posted: Sun Sep 09, 2012 4:46 pm
by ZepinAtor
gander wrote:I think based on the measurement by Competitive cyclist he may even get away with a 55-56cm frame with a 90 or so mm stem.
Yes, you're probably correct, but I was being very conservative with my opinions & trying to tread lightly on the subject. Also not sure if the measurements being entered are accurate although considering the OP's back ground I would hope they are re:-inseam accuracy ?

Re: Unusual bike fit problem

Posted: Sun Sep 09, 2012 5:40 pm
by cpical
ZepinAtor wrote:Wow, those are some challenging measurements. Very long inseam for somebody 174cm. You're built like a Giraffe with a short neck. I'm the complete opposite with an inseam of 85cm & 187cm tall. I ride a 58cm compact with a 115mm stem. Saddle height is 754mm from c of BB to top of saddle. (920mm from top of pedal).
He is a genetic anomaly! :mrgreen:
ZepinAtor wrote: Not sure if I'm seeing this right as camera angle could be dictating your saddle pointing down at the front. Sorry, but that bike looks all wrong from where I sit. Looks like somebody 6"3' has borrowed their mates 52cm bike. Then again I can't see you so who knows.
And he insists on running a 53/39 when his thighs are the size of my calves! :lol:

This morning he was playing playing with his saddle height, just like E Merckx used to do while racing. :shock:

Re: Unusual bike fit problem

Posted: Sun Sep 09, 2012 5:40 pm
by NeillS
Thanks man, yep the inseam measurement is 89cm or 90cm, crazy hey! I've measured it on two bike fit stands and done it myself at home a few times too. If you saw me you'd understand that the giraffe comment is pretty much spot on :lol: :lol: :lol:

The photo is a bit deceiving in a few ways - the bike is angled down at the front a bit and the arione saddle has a curve at the rear which makes it look pointed down at the front. If I click it back onto the next "notch" on the adjuster it points up slightly, but that puts pressure on my nether regions and it feels much more natural with it in that position.

I've borrowed my mate's mag trainer and I'm going to mess around with some motion capture software this evening and see what I can come up with. I rode yesterday and moved the saddle forwards and upwards again (slightly) which pretty much removed all my left glute soreness, woohoo! But then I rode again this morning and after 40km my right knee started hurting - whilst the left hip was perfect. So I'm certain I've got some weird assymmetry but I can't spot it yet. Perhaps something will show up on the video that the bike fit people can't see..... I'll report back with results!

Re: Unusual bike fit problem

Posted: Sun Sep 09, 2012 5:42 pm
by NeillS
compacts are for little girls and french men!

Re: Unusual bike fit problem

Posted: Sun Sep 09, 2012 6:30 pm
by cpical
NeillS wrote:compacts are for little girls and french men!

I see, I see! :mrgreen:

Re: Unusual bike fit problem

Posted: Sun Sep 09, 2012 8:07 pm
by ZepinAtor
NeillS wrote:Thanks man, yep the inseam measurement is 89cm or 90cm, crazy hey!
Maybe try removing your stilettos next time.

Re: Unusual bike fit problem

Posted: Sun Sep 09, 2012 8:08 pm
by twizzle
Hmmm, looks like NO setback on that bike! And to be UCI legal the saddle should be flat. Try getting the nose of the saddle somewhere around the suggested setback, but remember no saddles are created equal. I think you could benefit from watching the Steve Hogg bike fit videos.

I've moved more forwards now, but I also feel fairly balanced with my current setback, so perhaps it was a bar position problem that had me too far back. It was about 10cm earlier this year, but caused major back pain when I set up my 'cross frame. I literally had to get off the bike every 45 mins. Then I found my TCR to also hurt, when 6 months prior it was comfortable.

I also have long pedal axles, 6mm of spacers under the left shoe, plates to allow the cleats further back... it never ends. Losing 12kg since Chrissy has changed things as well.

Edit: I'd get rid of that seat post and put a micro-adjust in. Hmmmm.... Thompson Elite... 410mm. Or maybe the 330mm.

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Re: Unusual bike fit problem

Posted: Sun Sep 09, 2012 11:56 pm
by NeillS
There is 7-8cm of setback using a plumb line from the front of the saddle to the centre of the crank arm. I took some video footage which I'll upload - found some interesting stuff which could explain my problems

Re: Unusual bike fit problem

Posted: Mon Sep 10, 2012 7:07 am
by barefoot
NeillS wrote:There is 7-8cm of setback using a plumb line from the front of the saddle to the centre of the crank arm. I took some video footage which I'll upload - found some interesting stuff which could explain my problems
I immediately mistrust any fitment "rules of thumb" that use the nose of the saddle as a datum. Unless you're routinely riding with the pointy end of your saddle inserted somewhere uncomfortable, the nose position is irrelevant - a shorter saddle would change your "fit" without changing your position at all.

I have the opposite fitment problem with similar outcomes - I have short arms and legs, which lead to me being more comfortable on a tall but short bike. I've seen before that long limbed people need similar... I guess optimal cockpit length must decrease with deviation from "normal" body proportions somehow, and we're on opposite sides of the downslope.

Anyway, as a fellow short-bike rider, the first thing that I notice about your bike photo is the setback on your seatpost. No wonder you can't get your saddle far enough forward. You also mention notchyness when adjusting angle - very typical of a 1-bolt post.

Others have already suggested a Thomson seatpost - I'll broaden that to recommending ANY two-bolt clamp-on-top post. Something that looks like this:
Image

Swapping to one of them would immediately give you another ~40mm of forward adjustment on your saddle, if you need to go that far forward. For what it's worth, I have my saddles pushed as far forward as they will go, on clamp-on-top posts, on every one of my bikes.

Saddle angle definitely does look funny, but as you say, the bike is on an odd angle.

Your bars as as high as they will go... on that stem. Again, something I know a bit about. That's a very modest up-angle on your stem. Guessing at about 7 degrees. Stems can be had with up to about 40 degrees. Sure, extreme stems like these aren't fashionable, and will probably be heavy (they don't make ultra-light-weight components in fitment variants that are more likely to be used on a septagenarian's hybrid than on a go-fast race bike). You'll probably find them for sale as MTB parts, but they fit road bikes just the same. One of my road bikes, with a too-short steerer for more spacers, has a 100mm x 35dg up-angle stem, to get my bars high enough that I can reach them with my stumpy little T-rex arms. Another has a 65mm x 35dg on a big stack of spacers to get the bars up and back far enough.

To be honest, both could probably do with the bars being a bit closer/taller, but I'm really bumping up against the limits of adjustment by easily swappable components. You're still a long way from that limit. Trying a few stems and a zero-offset seatpost is cheaper than trying a new frame, and especially cheaper than getting the good people at Baum to build you a custom Ti frame to measurements that you've only guessed because you've never actually ridden a bike that fits like that.

tim