Mountain Biking - steertube spacing question

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MaxBrokeAway
08-02-07, 06:58 PM
Hey I just bought my Rockshox Revelation 426 Air U-turn (WHOO HOO!!!)

Im going to this from a Dart 2.

My question is would it be a good idea to decrease the amount of spacing between the headset and stem when I switch to the longer travel fork? Or should I keep the same amount of spacing I have now? Has anyone made a switch like this? What did you do?


cryptid01
08-02-07, 08:12 PM
Hey I just bought my Rockshox Revelation 426 Air U-turn (WHOO HOO!!!)

Im going to this from a Dart 2.

My question is would it be a good idea to decrease the amount of spacing between the headset and stem when I switch to the longer travel fork? Or should I keep the same amount of spacing I have now? Has anyone made a switch like this? What did you do?

The travel of the fork doesn't matter - it's the difference in distances between the axle and the top of the crown. If the new fork is taller A-C, you will need to remove the same amount of headset spacers from below the stem to maintain your original riding position. If that ends up being necessary, you can either relocate the spacers to the top of the stem (simple) or cut the fork's steerer tube shorter (pro).

MaxBrokeAway
08-02-07, 08:15 PM
well my new fork has adjustable travel of 100 to 130...so im guessing I should measure it while its the the 100 position?



Thanks


ed
08-02-07, 08:30 PM
Dang doood! You're going to be experiencing two extremes!

Nice choice of forks. If I were you, I'd leave a little extra spacing to play with until you get it dialed in to what YOU like. You can always cut it down later, but you can't add more steerer tube if you jack it up and cut off too much.

MaxBrokeAway
08-02-07, 08:35 PM
Yea, im gonna be going between XC and light freeride...its a trail/all mountain set up.

well...what if I take my spacing down 1/4 inch? Considering Im gaining nearly an inch in the travel even on the lowest setting?

RIC0
08-03-07, 08:48 AM
Yea, im gonna be going between XC and light freeride...its a trail/all mountain set up.

well...what if I take my spacing down 1/4 inch? Considering Im gaining nearly an inch in the travel even on the lowest setting?

I read somewere that for XC riding you don't want more than an inch of space between the stem and top of the tube. I recently cut about 3/8 inch off my steerer tube and couldn't believe the different feel it had. That little amount made a big difference.

MaxBrokeAway
08-03-07, 11:09 AM
I read somewere that for XC riding you don't want more than an inch of space between the stem and top of the tube. I recently cut about 3/8 inch off my steerer tube and couldn't believe the different feel it had. That little amount made a big difference.

Well the main cause for concern here is that im going from a zerostack headset to a standard...so im trying to factor in the size...before I had 1.25 inches of space between the headset and stem (headset was 13.1mm total stack height). And for my new rig Im probably gonna run .75 inches of space between the headset and stem(new headset is 27mm total stack hieght).

total of the spacers and headset for both rigs end up being around the same stack...but my old rig had more spacing between the headset and stem, and my new rig will have slightly less above the headset...but more below with longer travel on the fork all together.

opinions?

ed
08-03-07, 12:02 PM
Yea, im gonna be going between XC and light freeride...

Huh? Are we thinking about the same Revelation?

MaxBrokeAway
08-03-07, 02:27 PM
when I say light freeride...you should have emphasized the LIGHT instead of the FREERIDE. That would have been more accurate ;)

MaxBrokeAway
08-03-07, 02:39 PM
I have another question relating to this subject...I relation to Gastro's post

I know that Travel is the length the upper tubes can slide into the lower tubes before bottoming out.

But when I noted that my old fork's travel was 80mm...and my new fork's minimum travel is 100mm, Gastro said it doesnt matter what the travel is, but what the actual length is...does that mean that my 100mm Revelation could possibly be shorter than my 80mm dart 2? Can anyone speculate on this for me? I have neither fork right now, the dart is in the shop with my bike and the other fork is en route to my house at the moment...any help would be great!!

mech2o4
08-04-07, 01:08 AM
I got a question for you, did you consider what a larger travel fork could do to your frame? you might have added more stress in certain areas than your frame could handle... i mean i've heard stories of headtubes being completely blown off

MaxBrokeAway
08-04-07, 11:07 AM
i bought a new frame at the same time as the new fork...07 Motobecane Fantom elite DS...which if you buy the complete bike from Motobecane...its the same fork that they use on it.

MaxBrokeAway
08-06-07, 06:50 PM
Ok got my rockshox revelation today...SWEEEEEET!! But hey...can someone help me out with what the heck "external floodgate" is?

Dannihilator
08-06-07, 06:55 PM
It's a hopped up threshold valve. When the fork is locked out and enough force is placed on it, it will allow the fork to compress.

MaxBrokeAway
08-07-07, 12:47 PM
oh...so its a feature inside the lockout feature...sweet