Saddle height drop leads to sore knees.

[Wakatuki]

Tried to search, as I am sure it's been covered before but I could not find.
Suffering with groin sores for ages and then I was told to drop my saddle by a fellow bunch rider who said I was rocking on the saddle. (explains the sores) The relief in pressure was instant and amazingly my sores are now almost gone.
I dropped the saddle initially 15mm as suggested and my left knee hurt. So raised it 5mm now both knees hurt, but my backside is so comfy.

Am I right in thinking as I have dropped the saddle my knees will now be further forward over the pedal and I need to move the seat back or do I just continue to raise until a happy medium is reached... I have ridden this setting for 200k's so far but concerned about possible long term damage.
Cheers, Alistair.

[Gordonhooker]

When I got my latest bike I used this to determine what is best for me - now no saddle rock or sore knees.

http://www.ebicycles.com/article/determ ... eight.html" onclick="window.open(this.href);return false;

[RonK]

Well, I think a 15mm drop in one go is rather a large adjustment - I'd prefer to adjust in 5mm increments, but certainly not by more than 10mm. To me that much of a drop would require some additional setback.

It's worth spending some time reading Steve Hogg on bike fitting if you are having bike fit issues.

[Wakatuki]

Thanks, confirmed what I was thinking.
I think Im going to go back up another 5mm see how that feels. I do not want the groin sores back ,ouch.
Then raise 1mm until there is an issue then re drop 1mm. See how the knees go and then play with going aft....

[scirocco]

or do I just continue to raise until a happy medium is reached.

Yes. As high as possible without rocking.

[eeksll]

as someone on these forums pointed out to me, a short crank length is kinder on the knees as it reduces the hip->knee->foot angle. ie you dont lift your knee as high.

Dropping the seat height would effectively lift your knee higher, which would be worse for your knees.

http://bikedynamics.co.uk/FitGuidecranks.htm" onclick="window.open(this.href);return false;

[Dr_Mutley]

Depending on seat tube angle, if u want a simialar position relative to the BB, after u dropped the saddle 10mm, then slide it back around 5mm...

[Nobody]

Depending on seat tube angle, if u want a similar position relative to the BB, after u dropped the saddle 10mm, then slide it back around 5mm...

Sine 17 degrees (for a typical 73 degree STA) is 0.29 as a ratio. So dropping 10mm would require a saddle back move closer to 3mm.

[trailgumby]

I run 175mm cranks on the mtb and was going to go the same on the roadie I built up but th3 gruppo I ended up with had 172.5s.

I must say they are very comfortable to use despite the much more weight forward position and the reduced knee angle at.top dead centre is a big part of it I reckon.

If youre interested in the change a bike fit can make I have before and after vids taken by Blair Martin on my two mtbs before the Mont 24 this year. PM me and I can post links (I may not see the request if the thread drops off the new post list)

[Wakatuki]

Depending on seat tube angle, if u want a similar position relative to the BB, after u dropped the saddle 10mm, then slide it back around 5mm...

Sine 17 degrees (for a typical 73 degree STA) is 0.29 as a ratio. So dropping 10mm would require a saddle back move closer to 3mm.

Brilliant, thank you both.

Pm'd you Trailgumby

[RonK]

Depending on seat tube angle, if u want a similar position relative to the BB, after u dropped the saddle 10mm, then slide it back around 5mm...

Sine 17 degrees (for a typical 73 degree STA) is 0.29 as a ratio. So dropping 10mm would require a saddle back move closer to 3mm.

Yes - intuitively I would have gone for 5mm of additional setback for a 15mm drop in saddle height.

[Wakatuki]

After a bit of fiddling and a uncomomfotable SORE Sunday ride, I realised that I had raised the saddle to my personal limit. So I had a bit of rubbing and the left knee, jeepers, thankfully just a social with the wife who decided to not take the hilly way back, phew!
Dropped the saddle 2mm and back 4mm and been a bunch ride this morning feel, I still could go a bit lower could sense the rocking and the increased weight through the elbows. So will drop 1mm at a time, but will also take the seat back another 1mm. Getting there though.

[sogood]

Yes, bike fitting needs to be "holistic". Adjustment at one position, especially large, will affect the overall geometry of the rider, so adjustments in other departments are also needed. Following height, saddle, finally there's bar height and stem length. But one step at a time...

[NeillS]

Rocking on the saddle to me usually means one of three things;

1) Tight gluteals
2) Poor on-seat stability (think of this as core strength, but it's a bit more complicated than that really)
3) Saddle too high

With bilateral knee pain now, I would strongly suspect that your knees are trying to descend outside the line of the pedal centre on the downstroke, usually due to a wider than average pelvis OR poor glute function/length. Easy thing to do is video yourself on the trainer from the front and see if your knees are chopping out at the top of the stroke. If so, pedal spacers, longer axles, or an improvement in glute function is probably needed. This is just a guess but it's the single most common cause of bilateral knee pain that I see so it's probably not far off the mark.

[Duck!]

Yes, bike fitting needs to be "holistic". Adjustment at one position, especially large, will affect the overall geometry of the rider, so adjustments in other departments are also needed. Following height, saddle, finally there's bar height and stem length. But one step at a time...

Cleat rotation is also a consideration for a cause of knee pain, if it's not allowing your knees to track straight.