The 109% club and seat heights...

mattward1979

After having some back issues and hotspots, I decided to mess around with my setup, opting for a 109% seat height setup before playing with my cleats.

After getting my wife to measure my inseam (She worked in mens tailoring for years so im pretty sure its accurate!) I calculated the seat to BB length as 78cm.

I measured this on the bike to the current height, and was VERY shocked to see that my seat was about an inch and a half too high! So I set my seat to the 109% height and tried it out...

Now I know this is supposed to be a ball park estimation, but I felt really unsteady, my butt was coming off the seat on powerful turns of the cranks, and resting on the pedals my down leg was really angled..

Anyone experience this? Maybe my legs are just weirdly proportioned.. Either that or the 109% is just not accurate enough for the task... I raised the seat about 1.5cm and it felt a lot better

Ben6899

Have I read somewhere that the cycling inseam varies from a tailor's inseam?

I may have dreamt that or misunderstood what someone said in the past.

mattward1979

it was taken from the perineum to the floor, as recommended...

Most places will refuse an inseam measurement these days as its usually pervs looking for a nice shop assistant to handle their junk for a few seconds.. They usually take an outside leg measurement and deduct an amount (cant remember the exact details... she told me once, but in true husbandly fashion, I didnt listen entirely!)

nickel

I think a cycling inseam is measured from your crotch to the floor in vertical line between your legs, I thought a tayloring inseam was the measurement along the inside of the leg from crotch to the floor so may be longer?

mattward1979

if thats the case, it would have made the problem worse! I was nearly kneeing myself in the chest when in the drops..

Maybe I just have disproportinately long femurs...

Ben6899

I didn't use any method to set my height - it was trial and error (I suppose that in itself is a method!)... but one thing evident from bike fitting which I didn't realise before is that I am very leggy. If you're the same, then there's a very good chance the 109% guide doesn't work.

When I picked up my Bowery from the shop, the owner was amazed he didn't need to lower the saddle which he'd just inserted at an arbitrary height.

"Anyway sit on. Saddle will be too high no doubt, but we'll sort th- Oh. Right. Bloody hell."

mattward1979

hehe Nice

When I first got the bike, I was unsure whey they asked for my height etc as the setup seemed totally off for my size... but now im convinced they set it up correctly for a guy of my size off of charts, but my build throws that science in the bin...

Oh well.. Gives me an excuse for a pro-fit

sungod

fit based on measurements is not reliable

start with saddle level, use a spirit level - (depends on saddle, not all saddles work level), as a starting point, may need to alter angle slightly, but usually not by much

sit on the bike, clipped in, pelvis level, with the pedal at the lowest point and your foot level, your leg should be comfortably straight without stretching - i.e. you should be comfortably able to drop your heel a bit

check both sides, there can be differences in leg length

saddle position front/rear, aim for a position where with cranks parallel to ground, a vertical line drawn from the bony lump below the kneecap should intersect with the pedal axle

have a ride, if you find there's pressure/tension at the rear of the knee, drop the saddle 2-3 mm, if there's any iffy sensation at the front of the knee, go up 2-3mm

all the positions interact, and your cleats need to be in the right place, so if you adjust one thing you may then need to tweak the others accordingly

ShutUpLegs

Have I read somewhere that the saddle needs to be level with the top of your hip bone when standing off the bike?

I may have dreamt that or misunderstood what someone said in the past.

fludey

Just as a note the 109% rule I think you will find is top of seat to pedal spindle not the centre of the crank :?

So you possibly are too high!

I found the one that works the best for me is aim for 25-28 degree bend in the knee at 6 oclock, there is a special tool you can buy to do this...me I used a cheap protractor and some cardboard and made a 28 deg template!

MountainMonster

I don't go by any specific measurements, I just go by the good ole viewing the angle my leg is at and adjust according. A slight bend is desireable, but nothing too vague or too drastic.

mattward1979

fludey wrote:

Just as a note the 109% rule I think you will find is top of seat to pedal spindle not the centre of the crank :?

So you possibly are too high!

I found the one that works the best for me is aim for 25-28 degree bend in the knee at 6 oclock, there is a special tool you can buy to do this...me I used a cheap protractor and some cardboard and made a 28 deg template!

The 190% is indeed to the pedal, but I deduct 175mm for the crank length to give the accurate measurement...

The angle + cardboard thing is just utter genius in its simplicity!! Im trying that first thing tomorrow

Will see how I get on with a 20 mile pootle after

fludey

You will need the help of a willing volunteer though to hold it up and make a judgement by eye...but I have to say did it on one bike and after one ride copied it across to my other ride seems to have worked out perfect ....but it may not suit all but worth a try.

mattward1979

fludey wrote:

You will need the help of a willing volunteer though to hold it up and make a judgement by eye...but I have to say did it on one bike and after one ride copied it across to my other ride seems to have worked out perfect ....but it may not suit all but worth a try.

that's what wives are for! She already had to measure me from the coin purse to feet, so looking at cardboard is a walk in the park!

Pigtail

I'm reluctant to admit this - because I could take some flak - but my bike hasn't been set-up at all!

My LBS recommended a 52cm allez. I thought it was too small (5'9" shortish legs, longer back I thought I was too far over the bars) I bought a 54 from ebay - pretty much unused.

I took it home - it had all been set-up apart from the bars, so I turned them round and tightened the bolts - and I've ridden it since - some 2000 miles or so without moving anything.

I did make some attempt to setup my cleats when I bought clipless pedals a couple of months later.

velvetytoast

Pigtail - I know what you're saying I did something pretty similar - then I finally had it set up at the LBS (£35) and it was unbelieveably better - I just didn't know what I was missing

ride_whenever

read absorb and understand.

Then hook up a webcam to the tv and do your own bike fit.