Bike Geometry, picking a new stem and handlebar

thegrayson

I have a 2002 Kona Firemountain, 18" frame, currently fitted out with a 100mm stem and flat handle bar, neither of them the original due to vandalism. There is a Rockshox Tora 318 U turn fitted, with adjustable travel 85 - 130mm, the original fork was 80mm. With all of the newer bikes coming with short stems and wider bars I'm wondering if this would work with mine? Does this sort of setup work with only certain types of bike or is it down to personal preference? Will it make a huge difference to the feel of the bike?

shm_uk

Personal preference mainly, depends what riding position you want to create.

Shorter stem and/or riser bar will shorten your reach.
If too short, it can make your riding position feel too cramped.
You may be able to move the saddle rearwards slightly to compensate for this.

Combined with a riser bar, you will have a more upright position on the bike.

Shorter stem will make the steering quicker.


If your original forks were 80mm, then running the Tora's at more than 90/100mm will change the bikes handling characteristics greatly. And may even over-stress the frame, potentially leading to damage/failure.

Koiler

changing the bar and stem wont change the geometry, only your position on the bike.

changing the travel of the forks will alter the geometry, the higher the fork, the slacker the head angle becomes, this also lifts the BB. as said above though, too much of a change, will significantly impact on the handling and could potentially damage the frame (or your face)

supersonic

130mm on a 2002 kona will make it pretty slack, especially the seat angle.

thegrayson

I bought the fork at my lbs on their advice, it was a good price and a decent fork, I didn't want to buy one online as I didn't know a lot about forks and wouldn't have been able to fit the headset. I have it set about 100mm and haven't noticed a big change. I do have a lot of discomfort in my hands and feel a little stretched out though, that's why I'm thinking about a riser bar at least, maybe changing to a shorter stem if that doesn't help. Would a 70mm stem make a huge difference?