Short stem or long stem?

[comtn]

This is true, everything on bike's front end has effect to handling, e.g. slackness, stem length&angle, handlebar rise&width&sweep and so on. However, I see that it is completely ok to change those elements a bit to get bike feel better for you. Setup from bike factory is typically not exact match for your exact body dimensions/riding style, so subtle changes in e.g. stem or handlebar are usually beneficial. I would not of course put e.g. over 100mm stem to Jam2, that would probably make steering too slow and cause also other unwanted things...

Good point tweaks can always be made. I've gone with taller bars. With an e bike I don't need the leverage lower bars gives you. I would rather have a more confident feel on the downhills and give up some climbing leverage. I really don't stand going up hills while pedaling anyway.

 

[cabbynate]

Always leave the thinnest spacer on top of the stem. You want to make sure that the entire stem clamping portion is gripping the steerer tube... especially with today’s modern stem designs where the steerer clamping area isn’t very high.

Excellent advise!

 

[GrandPaBrogan]

I really don't stand going up hills while pedaling anyway.

Same here.
I actually can balance better while seated and find that I actually don't need to spin with an overly high cadence on real steep climbs. Over longer milder uphill slopes, my Yamaha motor seems to prefer that I assist it by pedalling in a slower cadence.

See what I did there? I'm the one assisting the motor... the motor isn't assisting me!

 

[GrandPaBrogan]

The stem length and slackness are tied together. If you shorted the stem you speed up the steering. Lengthen it and you slow down the steering.

Agree...

But don't forget the fork offset (or rake) and the influence that has on 'trail.' The head angle, fork offset, wheel diameter, and stem length are conjoined quadruplets that like to play arm-wrestling using the BB as the bar table (if the riders butt is off the saddle). Where the bar table is in relation to where the wheel axles are - plays a big part on how nice the brothers are to each other.

Bikes are spec'd with different forks which may have differing offsets. More offset = less trail and less offset = more trail. Less trail = faster steering but less stable at high speed. More trail = stable at high speed but your handle bar will rise and fall when turning, and even more so the slacker the head angle is. Then there's the front tyre cross-sectional profile - whether squarish or roundish also has a massive influence in steering speed and response.

So looking at the stem length alone does not necessarily reflect what a particular bike is specifically set-up to be good at. Then there's rider preference...

 

[sdcoffeeroaster]

My 2018 Carbon Plus Focus has a couple of upgrades that have led me to using a 65mm stem with pretty good results. The bike was feeling a bit twitchy on the trail with the 50 mm Giant stem I was using. I also have a 29" wheel on the front/ 27.5 back. The Fox Forks have gone from 140 mm travel to 150 mm. But I think the Salsa Rustler carbon 15 mm riser bars, 11 deg back/6 deg up reduced the effective stem distance to about 18 mm. I noticed the improved stability instantly with the 65 mm stem out on the trail. No more twitchy side to side corrections. It did feel like a completely different bike and I'm still adapting to it but it does feel much better.

OK, correction to the above. I put on a 60 mm stem not a 65 mm. Just 5 mm more than stock but with the typical Giant 8 deg upward tilt. I also ended up sliding my seat forward a bit. It was already back beyond the "max" point so now it's inside the normal adjustment zone. I'm probably going to be selling my Anthem 2 now. I just don't ride it at all anymore. This Focus handles better and is way more fun to ride as well.

 

[sdcoffeeroaster]

I can enjoy a good trip with this wake 45mm mountain bike stem. This mountain bike stem only weighs 130 grams and is easy to maneuver with a 31.8 handlebar and a 28.6 mm steerer diameter. This 6061 T6 Aluminum alloy bike stem is my fave. Such an alloy is known for its good formability and malleability. Everything about this bike stem is solid, snug, yet lightweight and versatile.

If it's the stock straight bar or any other straight bar 45mm sounds pretty good. If the bar has an angular sweep back like the Salsa bar I'm using then I found 60mm worked better for me.