Lower back problems - road bike only

Penhydd

I'm having lower back problems (muscular) on my old Peugeot road bike (circa 2000 model) that don't appear when out on either of my mountain bikes.

I thought that the problem might be overstretching, but I've measured from the handlebars to the front of the saddle and the distance is the same as on my Cannondale full sus (52 cms). My hardtail mtb also has the saddle higher than my road bike.

I have a feeling that the road bike is too big for me, as I'm 5ft 4, but don't want to splash out on a new one until I find the source of the problem. Is there anything else I can change with the set up of the bike to see if the problem disappears?

softlad

Penhydd wrote:

My hardtail mtb also has the saddle higher than my road bike.

I have a feeling that the road bike is too big for me, as I'm 5ft 4, but don't want to splash out on a new one until I find the source of the problem. Is there anything else I can change with the set up of the bike to see if the problem disappears?

there's a clue right there...

ride_whenever

probably hip flexibility, I assume you have the saddle at the right hight relative to the pedals, if so, raise the saddle a bit.

Penhydd

If you place your elbow against the nose of the saddle, your middle (longest) finger should be approximately 60 to 80mm (or the approximate width of the knuckles on your other hand) behind the handlebar.
Measured this & the distance is about 40mm

Ideally the seat to crank distance (when at the furthest point from the saddle) falls close to 109% of your inside leg length, measured crotch to floor. Get this wrong and you’ll overstrain on your hamstrings, knees and lower back.

I am way over 109% on this measurement - probably the answer. TIme for a smaller bike as I can't lower the seat anymore.