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O.K. to run at least 1 alumin. spacer under stem for DH?

S.K.C.

Turbo Monkey
Feb 28, 2005
4,104
24
Pa. / North Jersey
Hey - did a search and came up empty so here goes:

I'm looking to upgrade to 31.8 bars for 06' with a 31.8 stem, but weight is a factor and so is rise. I have an 05' 888RC w/ Go-Ride Lowerider Crowns, and am concerned with the stem sitting too low and having the bars twist upon impact and hitting/damaging the adjusters at the tops of the stanchions.

I don't want to run direct mount, because I like the idea of certain components having some "give" in the event of a crash. Currently I'm running a 30mm Diabolus stem which is a bit on the short side for me (med. Demo 8 cockpit) but the 10deg rise is perfect. I already have the stanchions extended as far as I'd like them to be (from top of crown to the top of the stanchion just below the adjuster is 5mm)

A 50mm Diablous stem is too heavy(250g), for my ride so that's out. I was looking at Thomsons' X4 stem: it's 173g, and comes in a 50mm length, but it has 0deg. of rise.

If I got the new X4 from Thomson and put at least 1, spacer (15mm) underneath it, would that be O.K. for DH and FR use?

Would this create a weak spot on the steerer?
 

oly

skin cooker for the hive
Dec 6, 2001
5,121
1
Witness relocation housing
Just make sure your stem is grabbing the steer tube properly. I believe Thomson has specs on this for their clamp system. If it rides too high (like if your steer is too short) then you may damage things.
 

S.K.C.

Turbo Monkey
Feb 28, 2005
4,104
24
Pa. / North Jersey
...yeah I cut the steerer extra long, so that shouldn't be a problem. There should still be room for one 5mm spacer on top for the headlock/preload (Woodman) to seat properly.

lol... yup, 75g does mean a lot to me considering I'm racing a Demo 8. =)