Help! Lower back/pelvic pain

j.r.hawkins

G'day all.

I've been getting a few aches and pains over the last few months and I'm wondering whether saddle position has something to do with it, or whether I need to lift my game with stretching.

I'm using a slick-tyred Mongoose Tyax Super MTB for commuting from Allambie Heights to the Sydney CBD and back (17-20km each way, but hilly). I'd been running very comfortably for many weeks with the bar same height as the seat. Then, in an attempt to get a little bit more aero went to a 30-40mm lower bar. By the end of the first workbound trip I was sore in the left lower back just at the top of the pelvis at a point extending straight up from the top of the hamstring.

I put the original bars back immediately, but the issue has reappeared intermittently since. It reappears after the Battle Boulevarde climb and is quite uncomfortable by the time I get to the top of Allambie Road. Prior to this I could comfortably ride 5 days a week so long as I averaged < 83% of LT on the homebound trip. I'm 45.

My seat was the right height above the pedals per the zinncycles.com frame size calculator for my inseam length, and to reduce the likelihood of rolling my hips when climbing I've since lowered it 5-6mm or so. My leg is staight but not quite locked out when I rest my heel on the pedal with my XC SPD shoes.

Last night I did the plumb bob thing over the knee with the cranks at 9 and 3, and found that the string was a good 2cm ahead of the end of my 175mm cranks. The most I can move the seat back is a further 4-5mm, which I've done.

Your thoughts and suggestions are most welcome. This is seriously limiting my riding time and getting a little depressing.