Spacers on custom bike?

Discuss light weight issues concerning road bikes & parts.
wintershade
Posts: 242
Joined: Mon Apr 16, 2018 7:12 pm
Location: San Francisco, CA

by wintershade

Hi all --

I have a custom Stelbel in the works. The original design (per my request really) has a slammed stem or a 5mm spacer. It's a pretty conservative (i.e., not much saddle --> handlebar drop), so then I started thinking, perhaps I should have them put on a 10mm spacer, just to give me the option of dropping it more later, if I so desire? Though to be honest, I don't think that's likely, as this is going to be my "rain" bike (30c tires, full fenders, disc brakes), so nothing too racey.

So really, I probably just want to optimize for what "looks" the best.

Any advice?

by Weenie


Bigger Gear
Posts: 476
Joined: Fri Mar 27, 2009 6:58 pm
Location: Wet coast, Canada

by Bigger Gear

My thoughts are: You can always cut the steerer at a later date if you want. I would go for something like 10mm below and 5mm above. If you end up slammed and want to always leave it there you could easily cut 10mm off. Also, if you change components the stem stack can vary by quite a bit, for example a Thomson X2 is 36mm and a Moots Ti stem is 45mm.

mattr
Posts: 4673
Joined: Fri May 25, 2007 6:43 pm
Location: The Grim North.

by mattr

My custom was geared up around 10mm of spacers. Gives the option for changes in bar drop/shape and stem angle/depth and changes in flexibility.

It's been run at everything from 0 to 15 (with three different forks, half a dozen stems and probably the same again of different bars.

DJT21
Posts: 318
Joined: Sun Mar 27, 2011 7:35 pm

by DJT21

If you want something that looks the best, then you've also got to take into account the top tube slope and the stem angle. It's no good going for a horizontal top tube and then fitting a -6 degree stem, as it looks crap; a -17 degree stem with some spacers would look better.

Likewise, a heavily sloping top tube with a -17 stem (as you realised you needed the bars lower) also looks a bit rubbish.

wintershade
Posts: 242
Joined: Mon Apr 16, 2018 7:12 pm
Location: San Francisco, CA

by wintershade

DJT21 wrote:
Thu Jan 31, 2019 7:54 pm
If you want something that looks the best, then you've also got to take into account the top tube slope and the stem angle. It's no good going for a horizontal top tube and then fitting a -6 degree stem, as it looks crap; a -17 degree stem with some spacers would look better.

Likewise, a heavily sloping top tube with a -17 stem (as you realised you needed the bars lower) also looks a bit rubbish.
Interesting. I hadn't really considered the visual effect of TT slope and stem angle. Can you please elaborate further on what's optimal aestheticlly. The design being contemplated currently has 3 degrees of TT slope, barely perceptible, but will expose a bit more seatpost. I was going for a "classsic" look, given it's a Stelbel and all.

Seatpost and stem will both be painted to match, if that's a consideration, but not the bars.

Eleven21
Posts: 53
Joined: Sun Jun 25, 2017 8:08 pm

by Eleven21

DJT21 wrote:If you want something that looks the best, then you've also got to take into account the top tube slope and the stem angle. It's no good going for a horizontal top tube and then fitting a -6 degree stem, as it looks crap; a -17 degree stem with some spacers would look better.

Likewise, a heavily sloping top tube with a -17 stem (as you realised you needed the bars lower) also looks a bit rubbish.
I totally agree with this.

I recently had a custom steel frame built. The original drawing we agreed I. had it with a horizontal top tube, but the final frame actually has a very slight slope. It’s hard to spot it when a -6 degree Thomson x2 stem is fitted, but with a -17 degree it becomes much more obvious and looks daft IMO.

shimmeD
Posts: 487
Joined: Thu Jun 28, 2012 10:52 pm
Location: eNZed

by shimmeD

A 3° TT slope is between stems of 17° and 12°; either will look fine. The difference between the 2 stems is 5° equating to approx 10mm, so there you have the answer. Or have a custom steel stem made to perfectly match the TT and you're somewhere in between. Absolutely, slam that stem!
Less is more.

Bigger Gear
Posts: 476
Joined: Fri Mar 27, 2009 6:58 pm
Location: Wet coast, Canada

by Bigger Gear

I do agree with the sloping top tube sentinment. If the bike has a lot of slope in the top tube and then a -17 stem is put on I'm not a huge fan of the look. I have one frame that is about a -5 slope on the top tube, and it looks OK with a -10 stem but really looks best with a -6 stem.

However, on a bike with a horizontal top tube there is much less aesthetic effect to my eye, and any of a -17, -10 or -6 stem looks fine to me.

spdntrxi
Posts: 3146
Joined: Sat Jul 20, 2013 6:11 pm

by spdntrxi

when I get a bike... one of the first things I do is source another fork especially if I think it's a "forever" bike. Which is reality means I have alot of forks in my garage with no bike to attach to it.

RussellS
Posts: 873
Joined: Wed Feb 03, 2010 1:31 am

by RussellS

My OPINION is 5 or 10mm spacer below the stem looks great. Just a little to get the stem up and visible all by itself. When a stem is slammer with no spacers it can look like its part of the headset, headtube and not a separate piece. Not good. Agree with the others that the top tube and stem need to go in a straight line. Flat top tube then -17 stem to get everything on the same plane. Sloping top tube then a +6 stem looks good. Stem sloping upwards just like the top tube. But most of my bikes have horizontal top tubes and -6 stems with a couple spacers beneath the stem. Looks OK to me.

kgibbo1868
Posts: 285
Joined: Thu Jun 21, 2012 6:36 pm

by kgibbo1868

If you are getting a painted stem to match your frame you want to keep it, so give yourself a small spacer above and below if you think you might need it. You can alway cut the steerer after riding the bike for a few months if you are feeling like you don't need the spacers.
Pain is my friend!

maxxevv
Posts: 2004
Joined: Wed Feb 09, 2005 4:51 am

by maxxevv

A small spacer is better than having none. 5~10 mm would be useful.

Case in point being the use of integrated bars that might not have the stem angle you need or if want to adjust the bar height for say extended Century rides ? Of maybe that new fancy stem that has a slightly different stack height ? Or even a new headset that has a slightly different stack height ?

2lo8
Posts: 539
Joined: Thu Mar 31, 2016 10:32 am

by 2lo8

You could of course go for an ugly tall headset cover/volcano spacer. I think they look uglier than a normal ~10mm one plus a spacer, but they do let you pretend you are slamming the stem. If you have a horizontal top tube, as other people say, almost any angle stem works, but you can also use a -17 with spacers if you want to keep some extra steerer and not look too off.

A 6 degree stem goes with a ~11 degree sloping top tube by the way, give or take a degree.
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shotgun
Posts: 256
Joined: Tue Dec 30, 2008 3:38 pm
Location: Philippines

by shotgun

If you think you'll be more flexible in the future and still get a lower position, it'll be a mix of a -17 stem and an a slightly shorter headtube. As mentioned above, no use of having a slammed step if your headtube is really tall.
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by Weenie


wintershade
Posts: 242
Joined: Mon Apr 16, 2018 7:12 pm
Location: San Francisco, CA

by wintershade

Thanks all. The benefit of custom, is Stelbel can do anything I want, so no need to "compromise."

I'm trying to synthesize all this into "rules of thumb." Please correct me if I have any of this wrong.
-- Having 10-15mm of adjustablity is generally good. In fact, a 5mm or 10mm spacer can look better than none for creating some visual space. (My headset will be Chris King Inset 7, which is flat/flush with top of head tube). I can use matching Chris King spacers, which look pretty good.
-- If horizontal TT, -17 stem looks best, to get everything on same plane.
-- With heavily sloping TT, +6 stem looks best, trying to keep everything at the same angle.

But my bike will have a modest -3 degrees slope to expose enough seatpost to add some compliance. I am looking at using the Deda Zero100 stem, which is available in either 70 or 82 degress, so I guess that's the same as -8 or -20? So among those options, what's the best way to go?

Headtube is pretty average at 160mm with a 562mm top tube. So it's not one of those hideous trapezoidal-looking frames with giant headtubes for a "slammed" stem.

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