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View Full Version : Stem Length?



alleyoop
08-05-2008, 07:54 AM
I just recently got a new bike (https://www.ibexbikes.com/Bikes/ASTA-PRO-Details.html) to replace my old rigid Rockhopper. Of course, there was some question of fit, buying off the internet and all, but I had tried out plenty of bikes as well as making a matrix of all the geometries. The bike does feel like the right fit too me. However, I have had a chance to take it out on all my usual trails and am wondering if I need a shorter stem. How would I know for sure?

My gut reaction the first time I got on the bike was that I wanted to take out one or two of the risers and shorten the stem... though I don't have the experience to know if that is REALLY what I need to do. On descents I am feeling like I have to get back further than usual to feel comfortable/in control. Do you think that part of this is getting used to a front fork? Could coming down semi-technical descents compress the fork, changing the geometry to make me feel front heavy? Would a shorter stem let me transfer the weight back a little easier?

There are so many choices with the riser bars, flat bars, stem length, spacers... How does one know? BTW, the stock stem is 150mm.

jckid
08-05-2008, 04:40 PM
I don't think your stem could be 150mm. That would be extremely long! You might want to measure it (center to center). It's probably somewhere between 70mm and 110mm. Sometimes bike shops will let you borrow various sizes of stems so that you can see what's comfortable for you. I had a bike with a 90mm stem, but found that the reach was a bit too long. I changed to a 70mm stem, but I didn't really like how it changed the handling. I ended up getting a frame with a shorter top tube that I could run a 90mm stem on. It really is just trial and error. You'll probably have to try a couple of stem sizes and change the stack height of your spacers until you totally dial in your fit. Good luck!

Irulan
08-05-2008, 05:03 PM
Main thing is don't cut anything off until you are sure!!!

You might want to make sure the sag and compression is set correctly for your weight. The manual should be online if you didn't get a copy.

The typical "need to have stem shorter" feels like you are too stretched out, elbows locked, possibly no room in body English to move back. Also have you checked out KOPS for correct saddle position.

And, if this your first front fork, you might just want some time to get used to having suspension on the front. If you get too far back you lose control of the front of your bike. If the fork is set up properly, you can really trust it to eat up the terrain as you ride.

I.

MtnBikerChk
08-06-2008, 03:49 AM
My gut reaction the first time I got on the bike was that I wanted to take out one or two of the risers and shorten the stem...


You can take out the spacers and move them to the TOP of (above teh stem) and put the headset cap back on (that way you don't have to cut anything and you can play with the right height for you).

Those changes are so minor you can throw a stem in your pack and change in on the trail to try it out.

If it feels good - ride it!

(but yeah, don't cut unless you're sure LOL)

alleyoop
08-06-2008, 02:21 PM
Thanks so much for your suggestions. You are right, I did measure the stem and it is only 120mm... which I gather is still a bit long. I will see if I can pick up a cheapo 90 or 100 at my LBS and see how that changes things in the field. Good Idea about not cutting!!

withm
08-06-2008, 07:16 PM
I have 2 extra Bontrager stems that I will sell - $15 either one

90mm 17o stem (Bontrager) for 26mm bars
90mm 7o stem (Bontrager) for 31.75mm bars

If either of them will work for you PM me.

Martha