I weigh 350, 6'7", and started biking about two months ago.
I planned on doing city park style riding just to get out of the house, and maybe hit the trails every once in a while. The guy at the bike shop talked me into getting a Specialized Hardrock Comp Disc (which is a pretty beefy mountain bike), I was concerned about bike durability with my weight. I beefed up a few of the components such as the pedals (I cannot reccomend beefy BMX style platform pedals enough for larger guys, I love my Primo Super Tenderisers. I wanted clipless, but with a size 17 shoe, it really isn't an option).
Eventually I started riding on the road every day, and hitting the trails on weekends. So I bought slick tires for city riding since I didn't want to tear up my knobbies. Every Friday I would switch back to the knobbies and hit the trails hard on Saturday, and then put the slicks back on on Sunday.
This got annoying, so I hit the garage sales looking for a beater bike to ride on the road. I got a early 90s XC steel bike for $30, put my slicks on it, got another set of super tenderisers, and spent another $40 or so setting it up to run good. The deraillers sucked, so I just converted it to single speed (The deraillers sucking is probably the best thing that ever happened to me cycling-wise, getting home and laying on the bed after a long singlespeed ride is pretty much the same effect as taking ecstasy). It's a total beater, I don't even know what brand it is, the stickers had been taken off when I bought it.
The weather around here isn't too favorable, so I haven't even got to go to the trails on the weekends. I love riding my singlespeed beater around town anyway, so I don't even care. To me it's better to step out the door and ride, than to pack everything in the car, drive 40 miles, and then ride.
The moral of this story is, don't worry about getting a super beefy mountain bike just to support your weight. The Kona Hoss and the higher-end Hardrocks and the Rainiers and whatnot are great if you want to ride offroad, but you really don't even need that kind of beefiness. It's nice to have, but those bikes make terrible city bikes. The shocks will kill you on the road.
I'm mostly just typing this to lament on the fact that I have two bikes sitting beside me, a nice new MTB that I've invested about $700 in, and an old beater that I've invested about $70 in. The $70 gets ten times more use than the other one, and if it happens to break, it won't be a thorn in my side.
Any steel frame and any decent tires should be able to support you on the road. If you're doing hard trails, you may want to look into the Hoss or the Rainier or a higher end Hardrock or whatever. But just because you're large, that's no reason to ride a super beefy all-mountain bike on the street.
I vote something like a Trek Navigator, like the earlier guy said, simply because a new bike is more likely to get him more excited about cycling. When I first got into it, I shunned the people that said that it's best to get a used bike, but now look at what I did. I guess it takes a cyclist to really appreciate an old ratty looking hunk of steel.
Last edited by ponds; 08-09-05 at 08:27 PM.