Tall/large guy needs mountain bike sizing advice....
 

So I think I am confused on how to properly size a bike. I know the best way is to go get on the bike, but I am trying to get a feel of what I want to look at based on specs. Plus its hard to locate all the bikes I am interested in, in the sizes I would need. I have a Trek 7200 hybrid in a 25" frame right now. It has a stand over height of 34" and an effective top tube of 23.3". Overall this bike fits me well, when riding on the road that is. I tried taking it on the trails, and it didn't handle well for a few reasons. One of my biggest complaints was that the top tube seemed to be in my way. This really sucked because I felt like I couldn't stand up to pedal when needed on climbs. The bike just felt big and cumbersome on the trails.

I am 6'8", 285lbs. and have a 36" pants inseam. I tried measuring true inseam and got about 37", maybe 38" with my tallest shoes. Standing over my 7200, it feels tight on. I am guessing I need at least 1-2" more of clearance. I read a few places that you should have at least 3-5" of clearance between your inseam and stand over height, others say 4-6" or 2-3". It seems like some of it is preference, but I am wondering if there is more of a standard of what to look for.

I am looking at a few bikes...

Gary Fisher Cobia 29er
25.3" effective top tube, 31.7" Standover

Trek 69er 3x9 21.5"
25.1" Effective Top Tube, 32.2" Standover

Trek 6000 21.5"
25.2" Effective Top Tube, 32.1 Standover

Trek 4500 24"
24.2" Effective Top Tube, 35" Standover

Specialized Rock Hopper 29er 23"
26.4" Effective Top Tube, 34.4" Standover

Specialized Rock Hopper 29er 21"
25.6" Effective Top Tube, 32.9" Standover

I worry that the Trek 4500 and Specialized Rockhopper have too much stand over height. The Specialized seems to have the best top tube length for me, but it has .4" more stand over height. Seems like the Trek 21.5" size has the most "ideal" top tube length to stand over height. I think the Gary fisher would work too. By specs alone, they all seem like they would work because they all have a longer effective top tube length than my 7200. Granted, its more of an upright riding bike with different stem and handlebar setup, but still.

I sat on a Gary Fisher 26er 21" and it wasn't bad. The stand over height is only .2" of a difference between the 26er and 29er, so it was a close approximation. The guy at the bike shop thought the handle bars were too close to me, and it wasn't the best fit. He suggested the 24" Trek 4500, but looking at the specs, it does have a shorter top tube length. The stem on the trek might be a little longer though, but I am guessing that would come out to be the same. I am just wondering if it looked funny though, and if the fisher bike had 29" wheels if it would look more appropriate with me on it.

I guess my question is, am I looking at this right? My thought is that if the handlebars are a little short on the fisher, I can extend them out a bit. The guy at the bike shop recommended against it saying that I would have less control over the bike. So not really sure what is ideal. I do know that it seems the larger you go in frame size, the more parallel the top tube seems to be. This worries me based on my experience with my 7200.

For instance, here is the Specialized Rockhopper Expert Disc 29er in a 23" frame....

http://restlesschipotle.com/dallasmo.../my-bike-2.jpg

versus how its shown on the website...

http://www.specialized.com/OA_MEDIA/.../8192-19_d.jpg

My thought is the bigger the frame size and stand over height, the more parallel the bar will be and I would probably have the same climbing issue while standing up and riding. I am thinking its worth the sacrifice in an inch of effectivie top tube length in some cases, because I could always modify the stem to work.

Based on my research, that has been my logic thus far. I am thinking about this the right way? I would appreciate any advice, because again, its hard to find all the sizes I am looking for. It would be helpful to get an idea of what to look for so I can find those bikes at particular shops and try them out.

Depends on a number of factors, geometry of the frame, and the intended riding style, for example. With cmpact geometry, there will be more clearance on standover height than a traditional frame. If you are going to be riding offroad, then that standover height becomes very important. Nothing like the top tube slamming the boys on a landing to make your ride really painful. :eek: :twitchy:

Top tube length is most important on a compact.

I have the 7200 for on road riding, so whatever I get will be strictly for trail/singletrack riding. I originally bought the hybrid thinking it can maybe do both, but its not. It can handle some dirt trails, but nothing with fast changing climbs, descents, small jumps, and obstacles.

I think your getting a little too hung up on the numbers. If you're ordering a frame without the chance to ride it, they're sort of helpful sometimes. But in this instance- where you can test ride all the bikes, I don't think it's as important as you might think.

For starters, we don't know what kind of terrain you'll be riding. The geometry of most mountain bikes is always a compromise in some direction towards uphill or downhill or rough or smooth or whathaveyou- nothing will be perfect all the time. That's why I have two mountain bikes, and am always looking for more. :D

Test ride lots of them- preferably in similar conditions to what you'll usually ride. If you have to add a oddly sized stem or seatpost or something, it could be an alarm that it might be the wrong size for you- but not always.

Keep in mind the mountain biking is a very technical sport- as you learn better technical skills, how you ride and position yourself on your bike will change over time.

As far as terrain goes, I don't live anywhere near mountains. It will be nothing like that. I live in Illinois which is pretty flat. However the singletrack style trails we have around here are in somewhat hilly woods. The trail I rode on was a constant switch from climbs to descends. It was mostly a dirt trail but had some roots, rocks, and even a creek here and there. For my immediate riding, that would be the terrain.

My hybrid bike failed at times when I couldn't keep momentum. Or I lost the chain and had to stop once or twice. I couldn't stand up to pedal up the hill, The bike was physically preventing me from doing so. I couldn't tackle some of these climbs sitting down either, so a few times I had to walk the bike up the hill. Also, there were some times when I stepped off and couldn't stand on the ground and clear the frame because of some uneven ground. This is all what worried me about getting a bike with the same stand over height.

Now, in order to test drive all of these bikes I would probably need to make 2 hour road trips here and there to do so. My Trek dealer is a newer one, maybe like 6 months of selling Treks. They only had the 4300 mountain models and the 5.5 Fuel EX. None of which were beyond a 19" frame. They have more Gary Fishers, but no 21" 29ers, all 19" and under. Best I could do was sit on a 21" Fisher 26er. There are 2 specialized dealers in my area, but from looking at their online inventory, they didn't carry any of the 29ers, let alone a 21" or 23".

Bike stores, like any other store that would sell something in a size, carries the middle ranges. They do that because they are most popular and sell the most being that the fit the majority of the population. That makes it next to impossible to drive around town one day and test ride every bike I am interested in. On top of that, I wouldn't be able to test it in anything more than the parking lot. So I have to rely on specs and others experiences to at least know what to go find.

In reality, 23"-25" frames are made for taller people like myself. However, because of my experience with my bike and the 34" stand over height, I worry I might have the same problem with the bikes that are "meant" for people my size. I am sure the geometry being different, and the handlebars angled down and further forward would help compared to my hybrid, but I worry that if the stand over is 34"-35", and I need to stand and get a jump start on an incline I won't be able to.

Standover on a mountain bike is never as important as reach. I would strongly suggest you try and at least trail test some of the bikes you are interested in. Problem is although you may want the 23 on one bike that size may be way too big or small on another. 29 wheels and the fork travel make a big different. The more travel the "taller" the bike.

I worry because of your size and weight if any of those bikes will work for you. Most have a weight limit. As long as you plan on cruising and not doing anything crazy you maybe OK. A suggestion, Kona specifically makes a bike for larger people - the Kona "Hoss". It can handle your weight and I think comes in an extra extra large frame size.

PS: Why do you need to stand to do climbs??? That's what gears are for. Sitting in the saddle and climbing is much more efficient! Learn to drop your gears and rest up a hill!

Trek told me their bikes have a 300lbs weight limit. I asked about both full suspension and hard tail. On the Clydesdale MTBR forums, many guys my weight and more use similar bikes. The only time I would worry about weight is the rear rim, since that is all I have had issue with on my Trek 7200.

I don't need to stand to do all climbs. There was one spot in particular with my Trek where I had to stop and get sweat out of my eyes, clean my glasses. It ended up being near the foot of a steep hill and I couldn't get enough momentum sitting to pedal up in in low gear. It really would have been helpful to stand up and rid it, but I was unable to.

29" Wheels and forks do make a difference, but not on a Gary fisher. They are very similar, as all the specs are practically identical. They are designed that way. The guy at the shop recommended me a 24" Trek 4500, and that has the shortest reach of all the bikes, which is still longer than my 7200.

Well sounds like you know what you are doing.

I have to say, I bought all my bike "on faith". I did some research. Test rode some bikes and then bought my bikes (I have a 2002 Lemond Zurich road bike, a 2004 Specialized Stumpjumper M4 hardtail and a 2006 Santa Cruz Superlight) without riding them. The Zurich turned out to be too small but with some tweaking I've made do. The Santa Cruz and Specialized are perfect. Maybe blind luck, but i love both bikes. Just keep researching, know what you what and then try and find the best price.

Good luck.

Hey,

Interesting thread! Here's my two-cents worth...

I'm 6-9, 38 inseam, and 235. My mountain biking here in North Central Washington is "mountain" biking in the true sense (singletrack, climbs, descents, etc.)

What I've found is that stand-over height when climbing isn't a limiting factor, and I don't consider it in the bike's I ride. I'm more concerned about room in the cockpit ("reach"), so when I climb out of the saddle, I can effectively put power to the pedals, manage handlebar movement, and lean forward if necessary without worrying about my knees hitting something on the front of the frame or handlebars. This is very important, because I never stay in the saddle all the time, and on most trails I'm out of the saddle as much as I'm on the saddle. Proper reach enables me to go back and forth fluidly, depending on what the trail's doing.

I have to stand on steep ascents, usually in a taller gear on the small chainring, due to loose dirt and rock under me. The cadence is much like being on a stair-step exercise machine. If I use the lowest gear and sit and pedal, all I do is spin out. Again, proper reach is essential.

The only stand-over issue I monitor is saddle height. I often keep it much lower when on the trail so it doesn't get in the way, especially on descents.

Getting a smaller frame size means you have a small cockpit. Putting a longer stem to compensate works on the road, but will get you in trouble on the trail. For optimum control, you need the stem/bar steering fulcrum centered just forward of your head tube, not out over the front wheel. It's hard to explain, but I've tried it all different ways, and it's much safer to have the proper sized frame under you.

I have three Giant Rincons, all 25.5" frame sizes. One is an older solid-fork, that I use on the road. The other two are front-suspended mtb's for trail use. One is a 2007 model, which has a sloping top tube with much less stand-over height than the first two that have classic geometry.

You might try a new Rincon and see how it fits you. Bear in mind that you may have to look into custom wheels (I did, for Clydesque durability), and other component upgrades as your experience develops. But for starters, check a Rincon out...

This kind of nails it- especially in rolling midwest terrain. You'll spend a lot of time out of the saddle and moving your body around in the cockpit.

On XC type courses, I like a lot of reach as found on my 29er. On more technical stuff, I like things a little tighter and more upright as found on my Hoss.

Personally, I'd avoid buying a MTB based on measurements alone. If you have to, you have to- but I still haven't got a solid handle on what exactly works for me, but I know standover and reach alone won't give me the whole picture.

Thanks for the info 2tall, that is helpful and gives me a fresh perspective. I been on a real mtb trail, which was single track esque, once. All I know is that my 7200 didn't work for many reasons, but I still have fun and want to do it a lot more

The giant rincon I see on their site only goes up to an XL/22" frame. The dimensions seem quite small on the contrary. Based on what I have found then, the best options would be like the Specialized Rockhopper or Fisher superfly 100. Of course, the superfly is way out of my reach because of the price, I just hope they trickle down their XXL size to less expensive 29er models. Not really sure why they started with the most expensive on that one.

Indeed, I was not correct. My latest bike is an 08 Yukon in the 2XL (24") frame. I got it used, hence the confusion. My older Giants, also 2XL, are 25.5" frames.

The Yukon has disc brakes, and the sloping-top tube frame, as compared to my older Rincons. It's the same as the current 09 Yukon on Giant's website.

I mentioned the quest for Clydesque durability...so far I've had to replace the Yukon's saddle and post (the stock saddle rails bent after a few jolts, and the post wouldn't support the rails reliably) with an Easton Havoc post and a WTB Power V 8mm-rail saddle. Similarly, the wheelset, while okay for moderate use, is currently being replaced. The stock Formula hubs, especially the rear, aren't very durable, and I'm experiencing other issues with the current build. I'm going with a custom Sun rim/14g spoke/36 hole XT hub combo.

You'll probably experience the same with any mtb given your size and weight, so just a heads-up.

I don't have experience with any of the other bikes mentioned in this thread. It's very possible that there's a better fit and I don't know it yet. Some of the specs look pretty good, and personally I'd like to try out the Specialized Rock Hopper 29er 23". Askel's observation is right-on. Getting on a bike and seeing how it feels is much better than going by specs alone.

I have not bent the rails on my 7200 trek, but I think its because it has a suspension seat post. You can see from the pic I posted of the specialized 23" Rockhopper that the guy riding it is a clyde....

http://restlesschipotle.com/dallasmo.../my-bike-2.jpg

That seat looks mangled up. This is what I do not get from biker makers. If someone is large enough to fit on that bike, most likely they are going to be at least 200lbs. Probably more realistically 225-250lbs, or close to 300lbs in my case.

For what it's worth- the *only* saddles that have every survived underneath me off road have been those with titanium rails.