Frame size confusion

mikey567

Member
Location
Yorkshire
I'm a semi-retired male, late 50s, who is interested in recreational biking for fitness/fresh air. Mostly cycle paths + easy off-road trails.
So I bought a second hand Trek 800 mountain bike, with a 19.5 inch frame, 26 inch wheels.
I am 5ft 10, slim build, "normal" proportions, reasonably fit for my age. According to my web research, this frame size should be OK for me.
But it feels too small. When the saddle is down, I can easily rest my feet on the floor. After raising the saddle by a couple of inches, I find all of my weight is over the front wheels and I am staring towards the floor. And because the bike has short handlebars, descending any sort of gradient is a frightening experience. I'm thinking maybe this is a bike for a teenager.
I thought of maybe raising the handlebars, but the hex bolts seem to be rusted solid.
Have I bought the wrong size? Or is it something I will become accustomed to?
 

mjr

Comfy armchair to one person & a plank to the next
I find it hard to say from that. You could work through the helpful setup guide on https://wheel-easy.org.uk/bike-set-up/ but I think you will need to loosen whatever hex bolt is stuck. Is it the one on top of a narrow (quill) stem? That's a pig but fairly common so there are lots and lots of tricks. You may find some in the Vintage section on this site, including upending the bike and squirting penetrating oil, dismantling fluid or even cola down (up?) inside the steerer to try to eat the rust seizing the wedge... but you suggest the bolt is stuck solid, rather than the usual symptom of undoing the bolt not releasing the steerer... hmm, hopefully someone more competent will answer soon :smile:
 

Cycleops

Legendary Member
Location
Accra, Ghana
Should be manageable for you.
The correct position for the saddle is when seated with the pedal at six o clock your leg should be more or less straight. If you are leaning too far forward try moving the saddle back on its rails. You can swap or raise the stem with a shorter and/or higher one if you wish. Which he bolts are solid? Is it a quill stem or a fork with a threadless steerer?
A pic of the bike with you on it will help.
 
Last edited:
OP
mikey567

mikey567

Member
Location
Yorkshire
The handlebar has a quill stem. After using WD40 and the some penetrating spray, I still can't undo the hex bolt using an Allen key.
So it will be a battle. And even then, with such short handlebars do I really want to raise them? It will be even more unstable going downhill.
> If you are leaning too far forward try moving the saddle back on its rails. <
All of the bolts look to be frozen up, including the front wheel release and the saddle.
Pic attached. I've just raised the saddle a couple of inches from the default position, to give a acceptable 6 o'clock position.
 

Attachments

I'm a semi-retired male, late 50s, who is interested in recreational biking for fitness/fresh air. Mostly cycle paths + easy off-road trails.
So I bought a second hand Trek 800 mountain bike, with a 19.5 inch frame, 26 inch wheels.
I am 5ft 10, slim build, "normal" proportions, reasonably fit for my age. According to my web research, this frame size should be OK for me.
But it feels too small. When the saddle is down, I can easily rest my feet on the floor. After raising the saddle by a couple of inches, I find all of my weight is over the front wheels and I am staring towards the floor. And because the bike has short handlebars, descending any sort of gradient is a frightening experience. I'm thinking maybe this is a bike for a teenager.
I thought of maybe raising the handlebars, but the hex bolts seem to be rusted solid.
Have I bought the wrong size? Or is it something I will become accustomed to?
Looks like a small frame.
Right size. My 18" Trek 800 was right for me at 5'8". There should be another two inches of stem available, based on mine. Not light bikes, but utterly dependable.
 

crossfire

Well-Known Member
Trek 800 - isn`t that what Hobbes on Tour is using?
 

PaulSB

Legendary Member
@mikey567 I don't know if the bars are low or high but too low will cause you to lean forward and support weight through your arms.

Moving the saddle back won't make the bike unstable. In terms of saddle position if it's incorrect one of two factors comes in to play:

Too far forward and the rider is leaning forwards over the bars and front wheel and supporting a lot of weight through the arms. It can lead to the bike feeling small. This is what you described

Too far back and the rider will feel stretched as he/she reaches for the bar. This makes the bike feel to big.

The correct basic position is to be seated so that you sit bones are the main contact point with the saddle and support the body, the knee should be very slightly bent, +/-10% at most, when the foot is at six o'clock and the arms should have a slight bend in the elbow. You shouldn't be supporting your body weight through your arms, most of the support is down through the seat and seat stem - you shouldn't be able to feel this.

Bike position is very important and I'd say it's rare for a rider to jump on a bike and find it fits perfectly. My advice would be to get the basics right in the garage. Then go for a ride taking hex keys with you. As you ride you'll find you may need to stop and make very, very slight adjustments to seat height, position back/forward and, possibly, tilt. Make these adjustments in millimeters not big jumps as the smallest change can make a big difference.
 
Top Bottom