[martin shortt]

i have just put a 30mm stem on my dh bike and still trying to figure out if this is better than my old 50mm stem in terms of handling.

im riding a keewee cromo 8 with 02 monster ts.

after i put the 30mm stem on the front end felt slighlty more twitchy but easier to catch when the front washed out and possibly having more control over the bike.

comments welcome...

 

[Defenestrated]

A shorter stem will give you more control but it will also shift some of your weight rearward. Which could actually make you wash out more. In the end its a balance you got to find, everyone is different.

 

[martin shortt]

thanks,
will keep trying it out

m

 

[sittingduck]

I went from 50mm to 30mm on my hardtail, and it SUCKED. My bike felt like crap in the air-much sketchier. Switched back, and all is well.

 

[rosenamedpoop]

Here's a breakdown:

The shorter a stem is, the more directly forces are transferred from rider to ground and, visa versa, from ground to rider. Thus, if you desire a more responsive ride at the sacrifice of some stability, a shorter stem is in order.

Conversely, the longer a stem is the less directly forces are transferred from rider to ground/ground to rider. This effect is simply explained as increasing the rider's leverage over forces transferred from the ground.

The real world effect of different length stems can be thought of as the difference between driving a bus (very long stem), and a race car (very short stem).

That said, 20mm is minimal.

 

[Demomonkey]

I went from a 30mm to a 50mm on my trail bike and noticed a huge improvement in handling. With the shorter stem I was too far off the back and struggled to get decent grip in the front around corners. I only recently raised the spacer height by 5mm on my trail bike and got better handling again. Try different settings.

I run a 50mm on my downhill bike as well as my trail.

 

[Spokompton]

It also depends on the bike.

Some longer bikes handle well with a 30mm stem cause they are long to begin with. Riding the North Shore also feels good with a shorter stem where steeps are more important than cornering.

Although like said 50-80mm gives more bite in the corners and stability at high speeds.

 

[zero knowledge]

What determines handling in a bar-stem combo is hands/grips position relative to the fork steer tube (look at your bar-stem combo as a whole thing). So bar tilt (along with back- and up-sweep) will be another variable to the handling characteristics. As an example, a 30mm stem with bars tilted forward can be less twitchy than a 50mm stem with bars tilted back.

 

[martin shortt]

i guess its suck it and see really. will keep the 30mm stem on for a bit. my bikes increadibly stable at speed anyway, at least with a 50mm stem, as i have a 47" wheel base.

less typing, more riding required...

 

[Whoops]

plus you've got the 12kg of Marzocchi goodness upfront.

(Even though you ride like a girl). Any pics of your trip to France?

 

[martin shortt]

(sorry to digress, threads kinda closed anyway i guess...)

mr tobin i presume, or one of his cohorts...

and yes i do have the plushest monster t's around. letting the air out and creating a negitive air spring works an absolute treat. the forks gobble up every little bump and stone. the trade of is they bottom a bit easily. gotta sort that bit out yet, play with oil and preload etc...

have a few piccys of morzine but no real action photos.

will email when im back from hols.