When I bought my Specialized Hardrock off Craigslist it needed a tuneup so took it to the local bike shop and had the brakes fixed and the wheels trued. Rode it a couple hundred miles with no issues and then had LBS put semi slicks on it since the majority of my riding is on hard surfaces (MUP, highway and packed double track).

A couple weekends ago I took it back to LBS for a check over since I was going to attempt my first organized ride doing a 40 mile route. LBS said rear wheel had 4 broken spokes which he replaced and that he had to "dish" wheel". The wheel was a little wobbly before that's why I took it in for the check.

I was able to keep up pretty well with a pack of "B" pace riders for about 20 miles, losing ground on the hills but catching back up on the flatter stretches. Then I gradually began to fall farther and farther behind and eventually couldn't make it up the hills without getting off and pushing. I really didn't feel all that fatigued so checked the bike over and the rear wheel was really wobbly, scrubbing on the brake pads enough that it would stop the wheel when spun. Made it about 25 miles and finally was picked up by the SAG vehicle and my day was done. One of the spokes is really loose so I guess more broken spokes.

My questions are: What is meant when a wheel has to be dished? If I need to replace the wheel where would be the best place to get a replacement. Wheels are 26 inch.

Sorry for rambling, I tend to do that. Any opinions, comments appreciated.