I have built up a training bike out of an old mountain bike I had. Basically it's a road bike wannabe, it has drop bars, full rigid, and semi-slicks. I built it to ride on the road during the week, just for exercise. I spent my money on a downhill bike instead of a nice road bike, but I still needed the exercise. Every time I ride it, 2 hours later my left nad will start aching, it's never immediate, or during the ride, and it lasts for a day or so. I didn't put 2 and 2 together at first, ended up going to the doctor and the idiot treated me for an infection, but it's the bike. I have had this bike since about 1996, quit riding it for awhile, then I made it a dedicated bike to do nothing but sit on the trainer, and I had no problems. As soon as I put semi-slicks on it and the original rigid fork back on it and actually rode it on the road and not the trainer, that's when the problems started. I am tempted to sell it and get a real road bike, but I'm afraid that it'll be even worse due to harder tires and more of a drop position. I don't know if it's the bumps, the geometry, the seat angle (flat), or what. I want to say it's the drop position with that bar, but it happened before I put the drop bar on there. It's happened on two different seats. Last time I rode it, I figured out that it was the bike, but I thought it was because I was trying wheelies and jumps and other crap that you shouldn't do much of on a road bike, but I've ridden it on the road only with the same results. It's only happened like 4 times. Sometimes I get the same symptoms except extremely faint on a normal mountain bike, but it's extremely rare, and extremely slight when it does happen. With this other bike, I can ride 3 miles on the road and I'm hurting for an entire day. Obviously I know what the problem is now and I won't be getting on it anymore, but I hate to do that, I've had it for 8 years, and I can't sell it for much, but I hate even worse that I don't know what the problem is. I'll be scared to buy a real road bike for fear of the same thing happening. Luckily I have a friend that works in a bike shop, so I could demo some real road bikes, so that's not a huge deal, but it still sucks that it's a trial and error thing with a good amount of pain at stake. Anybody else ever experience this? Any ideas? Thanks.