Every time a pic of someone’s position comes up it seems like there are several comments on here saying how they hate to see spacers on a bike like that, but I’ve yet to see anyone explain why they say that.
When I got my bike it had only about 5 cm of drop, with one 1" spacer. I flipped the stem and moved the spacer from below the stem to above it, giving me about 12.5 cm. I have ridden it like that for several years with no problems. Just didn’t feel like messing with cutting the steerer tube and I figured it couldn’t hurt to have some extra leeway incase I want to change position later.
So…from a mechanical standpoint, does having spacers cause a problem or issue of some kind? Or is this just about aesthetics?
I am interested in this also. I have a whole bunch of spacers on my bike. Now, not all of us can always get down as far as others. So, what are the options? If you cut the folks too low for what you body can take, I assume you are forced to buy a new folk? Would be nice to have some flexibility on how high or low one puts the bars, just like one can adjust a seat.
Depends how many spacers. A big stack of spacers on a overly long steerer tube is not a good thing from a structural/mechanical perspective. It also looks ugly.
I have a couple of spacers above my stem on both my road and tri bike. I never cut the steerer right down just in case if I sell the bikes the new owner may not wish to ride as low.
spacers above the stem are purely an aesthetic concern, but helps if you want some leeway in later moving your stem up (or ever selling your bike or fork to someone that is taller or likes a higher position).
a lot of spacers below the stem can be a structural and safety issue. generally, you want to avoid having a very tall spacer stack below the stem, but how tall is acceptable depends on a few factors:
-how many individual spacers (i.e., six 5mm spacers, or one 30mm spacer)?; fewer big spacers is better than many small spacers
-how tall is the total spacer stack?; lower stack is better
-what is the material of the steer tube (carbon, Al, steel?); steel and aluminum tubes can tolerate more spacers, carbon fewer
-what is the diameter of the steer tube (1", 1 1/8")?; bigger diameters can tolerate more spacers
-what is the wt. and size of the rider?; bigger, stronger riders put more wt. and force on the bars
-what kind of riding? (track sprinting? 40km TT)?; obvious but certain kinds of riding put a lot more force on the bars
Some forks even have fairly strong recommendations as to how high your spacers can go underneath the stem, because of structural concerns. This may be more of a concern with carbon steerer tubes than with aluminum or steel.
Carbon steerer tubes with very many spacers are a safety issue. Basically, you now have a lever to stress your steerer with.
More commonly, the criticism is one of improper bike selection. Very few people ought to ride a P3 for long course, simply because it’s built to be ridden far more agressively than they’re able. If your P3 has a bunch of spacers you’d be better served by the longer headtube of the P2 (K, C, SL, … ).
As much as anything comments about spacers are shots at riders who think more expensive is necessarly better.
"This may be more of a concern with carbon steerer tubes than with aluminum or steel. "
Good point. The Reynolds Ouzo Pro Peleton on my road bike is a carbon steerer and came with very specific instructions as to how few spacers should be used.
So if I’m reading this correctly, the mechanical problem with it isn’t actually a problem with the headset and the spacers working together, it’s more indirect - the problem is if you have a lot of spacers, that means you have a lot of steerer tube outside of the head tube, and this causes too much torque (or whatever more appropriate Physics term applies here) on the steerer tube?
The folks saying spacers below the stem have a good point about creating extra leverage, etc. But I wonder if there have been actual tests done, or if this is simply theory?
I have 90cm of spacers on one of my bikes (yeah, three 30cm ones!!!)!
Sounds crazy to many of you, but I will say that I have ridden that bike around 3000 miles that way.
it’s more indirect - the problem is if you have a lot of spacers, that means you have a lot of steerer tube outside of the head tube, and this causes too much torque
sort of, but more accurately, the problem is having a lot of steerer tube outside of the head tube below the stem.
The Reynolds Ouzo Pro Peleton on my road bike is a carbon steerer and came with very specific instructions as to how few spacers should be used.
Which were out of interest ?
“Sounds crazy to many of you, but I will say that I have ridden that bike around 3000 miles that way.”
3000 miles isn’t very many. Get back to us after 30,000.
Is your steerer aluminum or carbon? The risk of a catastrophic failure is far less with metal than carbon, but either should be regularly checked regardless of stack.
Call the manufacturer of Reynolds, Easton, Time, Look and Alpha Q forks and ask them why they have specific recommendations for the use of headset space.
I think you will find the answers quite interesting.
No, I’d say 3,000 is far more typical than 30,000. What I’d say is that when we’re talking about front end durability I want the test pretty darn tough. Realistically, I wouldn’t ride a steerer that I didn’t think would last 100,000 miles. Life is too short for that stuff. And it would seem pretty long if I couldn’t walk.
As a necessary side effect to threadless headsets seems to be that people are going to ride with a mile of spacers, perhaps we need to bring back steel steerers. I bet the ride would be just as good as carbon.
I’m not a spacer hater. Just want to mention that I was fitted on a Cervelo P3 by a FIST fitter. My bike has a lot of spacers yet my back is quite flat and yet my hips are more open than my road bike. I agree, a bike with a huge drop in the front may be cool to look at. But the same bike fitted to the unique measurements of a particular rider will look different. Age, torso, arm length, flexibility all play a role.
Kinda makes me wonder: Are dealers (fitters) to blame?
As more expensive frames tend to be more aggressive, do they have an interest in selling aggressive frames? Is this why one rarely sees a P2 kitted out with DA?
Honestly, can anyone give me a reason why a P3 with a bunch of spacers is a better ride than a P2 without spacers?
Honestly, can anyone give me a reason why a P3 with a bunch of spacers is a better ride than a P2 without spacers?
From a very non-technical and not having read what I would assume is some wind-tunnel data on the Cervelo site point of view, just looking at it I would think that the seat tube wrapped around the rear tire like that would be significantly more aero than just the cutout on the P2. And I would think this would mean a shorter wheelbase which would make it more agile.
Of course that could all be just looks being deceptive and very smart marketing but I am guessing the P3 would be at least a bit faster all other things being equal.