alaska_guy

Hey everyone, I just joined and posted in the new member forum.

I basically have been out of cycling due to some back/neck/shoulder injuries. I am finally starting to feel good and I want to drop the weight I gained from being inactive for 2-3 years. Ive slowly been working out and finally feel good enough to start cycling again.

Long story short...

I am 5' 11"
30" inseam

I am looking to get a hybrid bike. The wife owns a 10 year old bike that is stamped 17.5", Her bike feels really good when I adjust the seat for me. I feel upright and natural with some slack in my elbows. Her is an actual hybrid bike with road tires. Says medium and stamped with "Gitche Gimme" on the frame.

I was given a Trek 4500 Alpha from my old man who is 6' 2". His alpha is stamped 19.5". I feel like I am hunched over arms fully extended and when I look up from the bike to look forward I feel like I am fighting my shoulders/neck due to the position. When I stand over the bike, I can barely just stand over it... The crosstube is hitting, no gap.

I measured the wifes bike from the handlebars to the center seat post and did the same on the Trek and there is 1" difference. I assume there is other differences as well, but that 1" difference on hunching over seemed to make a BIG difference. I rode the Trek around the block today and after my shoulders and neck were already hurting.

I rode the wifes around the block yesterday and it felt fine, natural and just overall comfortable.

I went to my LBS and was fitted on a Trek FX 7.2 today and he said a 19" in that style would more than likely be perfect for me but they only carry them in a 20".

I really liked the feel of the FX and the Allant series at my local Trek store.

I don't need or want disc brakes, I may do 100 miles a week max to get started... I will be towing a frame mounted bike trailer with the kid in it. I don't need suspension as I have always ridden hard tails without front shocks. 98% will be ridden on paved roads with maybe some small distances between asphalt.

Is there a huge difference between say 20" in a mountain bike vs 20" in a hybrid bike like the FX or allant? When I was at the LBS I had him size me on a Marlin Mountain bike and he said I needed a smaller size due to the frame design etc...


I know that was a lot, but basically want to see if its worth trying to modify the 19.5" trek that I already own by putting on road tires and adjusting the handlebars etc or if it's just a waste of time and cash.

I can get last years model FX 7.2 for $400 new.

Thanks!

gobicycling

If your wife's bike feels so great, buy it from her or replicate. It seems to me that a 19" is pretty big for someone your size. But, all bikes vary in size - one bike's 19" does not equal another's 19".

bikingtotown

I would consider how you plan to ride it as well. Smaller is better to control to avoid bumps and obstacles so it proly be good choice for hauling trailer with precious cargo. I had a 20" trek fx which I was on small side edge of size chart for at 5'9 I rode on all different types of pavement and the bike still felt small but great control-wise. Disc brakes might be best since your going to have that extra weight of trailer or make sure to have them checked up now and again.

alaska_guy

I did a few online calculators and received the same results. I used their method to measure myself properly... Seems I may need an even smaller bike as my inseam is 29".

It seems I can't post urls...

Basically an online calculator for mountain bike says

Center-to-center (c-c)
15.7in to 16.2in

Center-to-top (c-t)
16.3in to 16.8in

Note: Manufacturers measure seat tube in either center-to-center or center-to-top measurements. Which measurements is indicated inside each bikes sizing chart.

It also stated general rule of thumb online was you should have 2" below you and the cross bar. Is this still standard? a 19.5" bike I have zero room. Seems odd if this is true the sales guy wouldn't have caught it and said oh that bike is too big. I had 2 different guys size me and they both wanted me on a 19". I was sitting on the bar with both sales guys.

bikingtotown

Online calculators are very general but good plce to start. Mountain bike fitting is usually smaller then hybrid you you ride on mostly smooth pavement. And different bikes types/ brands fit in very different ways with sloping tubes among other things. Top tube and reach is very maybe most imporant as its much easier to raise your seat up and down then correct reach distance. Best way is to test ride the bike you want on the terrain you plan on riding it

alaska_guy

Thanks, so the 19.5" mountain bike that I have, if the reach seems too far away lowering my seat may fix that? That seems to be my main issue, reach is too far and causing shoulder pain to look up. The wifes stem tube is 7cm to the forks, the old mans is 10cm to the forks. There is also a 1" difference between the seat post tube to the stem between the bikes.... So basically would have to shorten the bike up 2" to get the distances about the same as the wifes where I like it if I was to keep the old mans bike and modify it to fit me? I will hit a different LBS and see what they say... Just seems a 19-20" bike is just too big for me...

Inseam: 29"
Trunk: 24"
Forearm: 12"
Arm: 21"
Thigh:22"
Lowerleg: 21"
Sternal Notch: 59"
Total Body Height: 71"

bikingtotown

Competitive cyclist.com has an in depth calculator for putting in lots of measurement think its more for road bikes but it's still just general guideline dif body/ bike types and w prior injuries you might be more comfortable on quite diff size. Also usig lots of measurements makes things more complicated. Reach is number one and having good seat height while riding. Changing seat height isn't going to effect reach a whole lot but position on the bike. Seat to handle bar ratio. Also have to be able to reach pedal comfortably. I've been getting lower back pain after long rides and I think it's because I've been riding with seat a bit too high.

alaska_guy

I decided to go with a Scott dealer in town. They sounded way more competant. Guys had been riding for over 20 years, won races etc. They custom cut and measure everything to me as long as I buy the expensive bike. Said it normally runs $300. So I think I am in good hands now. Bought the bike and go back later to get measured/fitted.

Thanks!