Large chainring might be knackering my knee

Dizzy12

Hi Guys/Girls,

I'm knew to road cycling; however, I've been mountain biking for over a year or so. I've got 2*10 Tiagra set on my bike with a 50/34 up front.

I find that I mostly, unless I'm going downhill or on flats, feel more comfortable pedalling in the smaller chainring as this allows me to keep my cadence up and also it seems to be gentler on my knees. Anything wrong with this approach?

I've seen many roadies pedal quite hard with a medium cadence, using their larger chainrings, yet this seems to make my left knee twinge after a while. I did 40 miles at the weekend with varying approaches, but prolonged use of the large chainring, outside of descents, just caused discomfort.

Advice and thoughts are much appreciated.

d

alihisgreat

i prefer spinning as opposed to grinding out a big gear too.. there is nothing wrong with that approach!

if its stopping you from injuring yourself then that's a good enough reason to do it?!

http://www.bikeradar.com/fitness/article/technique-cadence-matters-16394/ brief article on Cadence.

It is worth training and pushing on bigger gears though as this will increase your strength -> just don't feel that you have to do it all the time!

Zoomer37

Your seat height correct?

Your knee should not give you pain just because your using the big ring. Saddle to low + big gears can however cause problems. Leave it a few days for your knee to rest then try raising the saddle height and see how you get on

Wirral_paul

Fore / aft position of your saddle can also cause knee pain, as can incorrect alignment of your legs (i ride with a 1.5deg varus wedge in my shoes after a full professional bike fit to identify and correct this)

gmacz

I pefer bigger gears and slow pedal speed.
Just tire myself out with all that pedalling and not going anywhere.
Sounds like you are getting knee pain when you have to put the power down.
My guess would be seat height, raise the seat and try again.
Too low and the wrong muscles are used and the knees take the strain.
Too high and I think it hurts at the back of the knee.

Monty Dog

Is the knee pain front or back; or side-to-side? There are lots of factors at play here including saddle height, shoe / cleat / pedal alignment or your own physiological make-up and would suggest that you seek a specialist rather than online diagnosis.
In terms of favouring smaller gears and spinning, that's not a problem - in fact it's biomechanically more efficient - a common problem for many folks new to road bikes is riding in too high a gear at too slow a cadence. Unless you are looking for improvements in your performance or want to reduce the incidence of knee pain, then carry-on would be my advise.

Dizzy12

Guys, all your pointers are excellent. Much appreciated.

@Monty Dog The twinge is at the front of the knee.

I'm going to see my local bike shop this weekend, for a service, and they're going to look into as well.

cyberknight

Front of knee hurts= Seat too low and/or too far forward, straining knees Raise seat; may need to move seat further back as well

pasted from bikefit 101

I ride a 50/34 compact and i generally ride on about a 15 tooth on the back(mid cassette ) for a on the flat speed of 20 mph when commuting with panniers or spinning on a club run .

liquor box

Dizzy12 wrote:

Hi Guys/Girls,

I'm knew to road cycling; however, I've been mountain biking for over a year or so. I've got 2*10 Tiagra set on my bike with a 50/34 up front.

I find that I mostly, unless I'm going downhill or on flats, feel more comfortable pedalling in the smaller chainring as this allows me to keep my cadence up and also it seems to be gentler on my knees. Anything wrong with this approach?

I've seen many roadies pedal quite hard with a medium cadence, using their larger chainrings, yet this seems to make my left knee twinge after a while. I did 40 miles at the weekend with varying approaches, but prolonged use of the large chainring, outside of descents, just caused discomfort.

Advice and thoughts are much appreciated.

d

I have pretty much everything possible bad with my knees, but I rarely get pain...anymore. I have my pedals fairly loose so there is a bit of play for my feet to change angle if they want to. I also try to concentrate on my knee being above my foot all the time. This sounds obvious but remember your knee is a one way hinge, if your knees are angled out from the frame then you are exerting pressure on your knees.

blackhands

I can't see how the fore/aft saddle position has any effect on knee pain - as long as the correct saddle height is maintained, the moving the saddle in an arc about the bottom bracket will maintain the same relative position.

Leg strength is immaterial for normal healthy people. As the OP has only been riding for a short time I doubt that he has developed sufficient aerobic power/endurance to push bigger gears for long periods of time.

cyberknight

Moving the seat forwards reducing total seat height as you are shortening the distance from where you sit to the pedal , the same is true for pushing the saddle further back increasing total overall height .2 mm forward = 1mm effective height ( i think ).
Best way to try it is to place a mark on the saddle and then move the saddle forward and you will find that the distance from BB will decrease .

blackhands

cyberknight wrote:

Moving the seat forwards reducing total seat height as you are shortening the distance from where you sit to the pedal , the same is true for pushing the saddle further back increasing total overall height .2 mm forward = 1mm effective height ( i think ).
Best way to try it is to place a mark on the saddle and then move the saddle forward and you will find that the distance from BB will decrease .

Assuming that you are commenting on my post above - if you read it again you will see that I mention keeping the saddle height the same - FYI "saddle height" is normally meant the distance betwen the \BB centre and the top of the saddle.

cyberknight

Indeed i did , my comment was based on keeping the saddle height the same, if you push the saddle further back on its rails you increase the length from where you sit to the BB assuming you sit on the same spot on the saddle as you are decreasing the effective seat tube angle .

pasted form google -fu
As you move the saddle forward or rearward, you are also changing the effective saddle height, relative to the cranks, since the saddle rails are usually not perpendicular to the seat tube. So be prepared to change the seat post extension as you adjust the fore-aft saddle position; lowering the saddle as you move it back to maintain the same leg extension, and raising it as you move the saddle forward.

Means of adjusting saddle set back.

The saddle set back is normally adjusted by slackening off the seat clamp bolt or bolts and the sliding the saddle forwards or backwards to set the desired saddle set back, due to the angle of the saddle rails it may be worth checking, and if necessary re-adjust the saddle height.

http://www.hewittbikefitting.co.uk/fitt ... ensions-2/