Originally Posted by
Kapusta
I suggest dropping the focus on standover. Sizing modern MTB bikes using standover is a bad idea, and nobody who understands modern MTB fit well would do so.
Go by the length of the reach and how it feels actually riding it.
Frame size for mtb IS very important, because getting the proper frame reach is very important. At least if you are going to be riding technical terrain. If the bike is for more casual riding or mostly paths and rail-trail stuff then you have more leeway to make adjustments with stems length and such.
At 5’6” you could be a med on some bikes and small on others.
If you do decide to make standover a deciding factor (which is a big mistake, IMO) then look for a model that has standover AND proper reach. Going down a size in a particular model just to get more standover can leave you with too small of a frame for the 99% of the time you are riding it rather than standing over it.
As far as whether to go with the shops rec or the manufacturer’s guide… depends on the shop. Did they have you ride the bike around the parking lot and see how you positioned yourself or did you just sit on it in the shop?
Try searching forums like MTBR (there is a Trek sub-forum there) to see how others sizes up on Roscoes.
It was raining when I bought so they let me take the bike home to ride and said as long as there was no major damage I had 30 days to decide. The only reason I mentioned stand over height is it's the only thing I could think of and I don't know a lot. I won't be doing anything technical. It's been a progression to get here from where I was a few months ago. The bike shop had me stand over it, sit on it, ride it at home and has been great about communication. I think I'm just overthinking. At 5'6, there have been a TON of times I've purchased items that just didn't fit (bows, guns being the most common) and the learning curve on fit there was expensive. I didn't want to even risk it, so I'm trying to triple check everything. Riding it feels great, I did six miles the first day on loose gravel and dirt road hills. Which is 90% of my riding. I found I really noticed the difference in gearing from the Trek 1x10 to the GT 1x12. My low end made for easier climbs and on the high end I can hold a faster pace easier. So I'm liking that. The fork is also night and day. We get some washboard out here and the Rockshox seams to react smoother and more quickly where the spring fork on the Trek seems to always be "catching up". I've made a few connections locally and will be going from my trail rides to some low end downhill next summer. So hopefully my understanding of this stuff will go up the more I do it. Right now it's hitting hunting season and this is going to let me get some distance off road where people usually can't get to. Other than that, it's fitness. I run a lot but I notice that the bike is far easier on the joints. I tend to enjoy a 6 mile bike ride far more than a 6 mile run these days.