I have been traingin for my departments Bike Patrol and have managed to loose 9lbs in the last month and routinely do 10-15 rolling miles a day. As it is now I can only afford the bike I have now for Training, I ride a Marin at work. My current steed is a Mongoose D40r that I bought 10yrs ago. What inprovements could/should I make to that bike to improve my gains and training(parts?). I've been riding that bike for 10yrs and it fits well, plus I can't afford another at this time. Bring on the wisdom.