Please see here the super easy to use thumb screws that are in place on the Planet X Stealth Carbon Pro frameset. This is a SUPER easy to use and adjust system. The second photo is of a huge seller bike with the PITA horizontal drop outs with a wheel adjustment. From what I had done the 2.5mm adjustment screw is nothing but a pain in the rear as compared to the Planet X design.
Just to offer a counterpoint –
Sure the PX system looks easy to adjust, but ‘system B’ looks:
Simpler
Stronger
Lighter
More Aero
Unless you’re changing wheels a lot, how often do you really have to mess with the drop out adjustment?
Chip, take another of the PX in focus, would you, please? I can’t make out the detail that you are referring to.
Cheers.
Just to offer a counterpoint –
Sure the PX system looks easy to adjust, but ‘system B’ looks:
Simpler
Stronger
Lighter
More Aero
Unless you’re changing wheels a lot, how often do you really have to mess with the drop out adjustment?
Simpler - to me it looks as simple as the other way
Stronger - wheel isn’t loaded in the fore-aft direction, so strength isn’t an issue. Besides, the skewer putting preload on the dropout is what will provide a reaction point
Lighter - perhaps by a few milligrams; you trade the thumbwheel for cutting more material out
More aero - are you serious? I’m sure the derailleur pukes up the aero back there. I guess if you’re worried about being that 1 second faster over 112 miles…
I’d by a bike with that mechanism. Definitely a better design solution than what’s on the other frames out there.
I get the whole thing with the horizontal drop-outs. However, what I would like to see and maybe this is impossible is a bike with horizontal drop-outs that is easy to take the back wheel on/off. I like to think of myself as being reasonably handy around a bike, but no matter how hard I try I get grease and dirt up to my elbows when getting rear wheels on/off a bike with horizontal drop-outs! MissP had one for a few years and it was always a struggle. With regular drop-outs the wheels go on/off in seconds and your hands can stay completely clean.
It is very easy to very a rear wheel with a horizontal rear dropout, you just do it a little differently than with a conventional rear dropout. Gerard has shown one way to do it simply. Also, it is more difficult to remove a rear wheel with a conventional dropout when the manufacturer has tried to tuck it close to a seat tube cutout.
Forgive my ignorance, but what is the benefit of horizontal dropouts?
That’s how they work on my Tiphoon. The thumb screw portion isn’t as big on my bike, but it’s the same sort of design where you can just use your fingers from the front without any tools.
My '05 Tiphoon, I might add. 
I get the whole thing with the horizontal drop-outs. However, what I would like to see and maybe this is impossible is a bike with horizontal drop-outs that is easy to take the back wheel on/off. I like to think of myself as being reasonably handy around a bike, but no matter how hard I try I get grease and dirt up to my elbows when getting rear wheels on/off a bike with horizontal drop-outs! MissP had one for a few years and it was always a struggle. With regular drop-outs the wheels go on/off in seconds and your hands can stay completely clean.
Steve,
So happy to read your post. I’ve been feeling like an idiot trying to swap my back wheel on my new QR Lucero. Your post summed it up perfectly. I have yet to figure out a way to change the wheel without getting grease all over (let alone how much longer it takes). To the first line in your post, what is the reason for having horizontal drops? All I can figure is that once you get the wheel in the drops, it naturally wants to stay in place. Is that it?
Steve
They use horizontal dropouts so that you can adjust the gap between your tire and the seatpost cutout depending on what size tires you are using. It’s easy to change the wheel…you need to pivot the derailleur a little as you remove the wheel, but you can do that using the derailleur body which should be clean anyways.
A standard forward-opening dropout requires the wheel to pull forward to remove/insert. On bikes where the wheel is recessed or protected by the seat-tube for aero-reasons, the wheel hits the tube and can’t be removed…or inserted for that matter. The standard dropout therefore limits how much shielding you can get from the recessed seat tube.
The rear-facing horizontal dropout allows the wheel to be cinched closer to the recessed tube, and removal/insertion never requires the tire to interfere with the tube; it only approaches from behind, so to speak.
I can see the planetx design allows adjustment with the wheel in place, when not tightened down. The cervelo screw can only be turned with no wheel in place. (maybe you can finger-tighten if the screw is well lubed).Is the thread all the way thru on Cervelo? then just insert the screw from the other end.
Paul
While I haven’t used the “allen bolt, accessed from the rear” system, my experience is that after a year or two of road grime the “thumb screw, from the front” adjuster gets very tough to turn, requiring a pair of needle-nose pliers to operate and sometimes stuck to the point that you break off the knurled wheel. The screws are often pretty small, risking bending.
Looks like the allen bolt allows you to use a tool to gain advantage if difficult and the position would keep the bolt hidden from road grime more than the front-accessed screw.
Is it really that hard to use an allen wrench?
Jodi
Is it really that hard to use an allen wrench?
Jodi
Yes, when you want to tuck the wheel in and have to take the wheel out, turn turn, test, out turn turn, test…just a PITA as opposed to a thumb screw. I on my old bike had to adjust when ever I would swap tubbie wheels (Zipp) for any clincher wheels.
Fleck,
I can’t remember where I read this, but it works. Shift down to the smallest cog in the rear. Then take the skewer completely out. Once you pull the wheel out you then only have to lift the chain enough to clear that last cog. You still get a little lube/grit mix on one finger but it’s better than on all 5. Reinstall is basicaly the same thing just reversed. It’s still not as easy as standard dropouts but makes it manageable on the roadside.
I never could figure out the moving the derailleur trick and would end up with crap all over my hands.
Simpler - to me it looks as simple as the other way
PX system looks bulky, and as other posters have said, looks susceptible to grime.
Stronger - wheel isn’t loaded in the fore-aft direction, so strength isn’t an issue. Besides, the skewer putting preload on the dropout is what will provide a reaction point
The extra cutout needed for the thumbscrew appears to be a weak point. (See also “lighter” comment, below)
Lighter - perhaps by a few milligrams; you trade the thumbwheel for cutting more material out
It’s not the weight of the thumbscrew itself, but the whole area looks like it’s been beefed up – possibly to improve strength.
More aero - are you serious? I’m sure the derailleur pukes up the aero back there. I guess if you’re worried about being that 1 second faster over 112 miles…
On a frame where the tire position can be adjusted within a milimeter of the seat tube, aero tube shapes, internal cabling, etc., etc. I’d say that little things like this do matter – for marketing reasons, if nothing else. A second cutout and protruding screw are also on the left side of the bike where the air is presumably cleaner than around the der.
I’d by a bike with that mechanism. Definitely a better design solution than what’s on the other frames out there.
EDIT: Ok, just noticed the bike doesn’t have internal cables…Frantic edit before sombody jumps on me for this egregious oversight. 