Hi guys , i have two pair of wheelset.
The first pair i use for daily purpose and training , and the second one is a full carbon wheel i used for racing and as back up wheelset.
the problem is , with the first pair the transmission works perfect but when i use the second pair the chain seems to jump sometimes and the middle gear do not work properly.

Is possible to set up a perfect shifting with both wheels?

unless the cogs are exactly aligned on both wheels... probably not, but it is very likely that a small adjustment of the rear derailler barrel adjuster will fix this

As mentioned, a "few" clicks on the barrel adjuster "should" restore proper shifting.
Keep track so you can turn it back the same amount when switching back to the original wheel.

To answer your question-
For a "drop in perfect" wheel, you'd have to add or remove a TINY" bit of spacing on the DS and remove/add the same amount to the NDS. (and "technically" redish, although the amount probably wouldn't be worth the effort.

You now have a non standard spaced wheel that may be 2X that bad on another bike.

If it was my bike, I'd add or subtract a spacer to one of the rear wheels until the cassettes matched. It's do-able, it just takes a little fussing.

Main issue is that (cassette) spacers are typically 1mm thick, and the cog spacing on (say) a Shimano 10-sp setup is 3.95mm. You're likely to be unable to do a change small enough to bring the two cassettes in line.

This said, if you don't want to eyeball it, you can measure the distance from the right axle face to the cog face on each wheel, and get a reading of the difference. If you're lucky it will be in the 1mm-range, and then you know which cassette needs an extra spacer; but if you find a 0.5mm difference, say, you'll find that although such spacers exist (Chris King makes them, for example), they are pretty hard to find.

Not true. the hub doesn't need to move, just the cassette.

cut shims from a beer can with scissors and place behind cassette to that the cogs are the same distance

from the dropout (and thus the RD) on both wheels.

No more true than my solution and lots of fun cutting spacers from a beer can?
This is a lot easier.
https://wheelsmfg.com/products/hub-p...e-spacers.html

What is not true is that you'd 'have to add...'.

I see a .5mm axle spacer to add a tiny bit, but don't see a -.5mm one to subtract a tiny bit on the other side.

Those are especially hard to find...

Have you actually done this?

Apparently you didn't notice the other sizes that you can combine, although I wouldn't bother with .5mm on the NDS.
And I do have experience with axle spacers.

In theory both approaches work, in practice one (axle spacing) requires dealing with both ends of the axle equally, and probably require removing the cassette + cassette body, the other (cassette spacer) only requires removing the cassette. On the other hand, I'm not sure I'd be very hot with inserting a soft aluminum spacer between a cassette and a hub. Remember, all this is to avoid a click or two on the barrel adjuster everytime the OP changes wheel.

Note that this exact problem is also often seen when cyclists put their bikes onto direct-drive trainers; as far as the bike is concerned, such a trainer is just another wheel.

Has anyone mentioned that if OP does a reasonable amount of training cog and chain wear will become a factor... Since much less pronounce on chain rings, how about not just changing wheels, but chain too. 2nd choice: changing training cassette onto race wheel. If this ain't news, sorry.

Probably.

You can get thin spacers to adjust cassette spacing from companies like Wheels Manufacturing or start from shim stock.

Standard axle spacers won't work with contemporary wheels that moved beyond 10mm threaded axles, saving weight with larger diameter aluminium parts that are lighter but have the necessary shear strength and stiffness. Mine have measured 12, 15, and 17mm in diameter. Those adapt to standard 10mm dropout slots with proprietary end caps, some of which can't be spaced like PowerTap hubs retaining the drive side cap and cassette with an O-ring in slots matching between cap and axle.

[QUOTE=Last ride 76;210611 changing training cassette onto race wheel. [/QUOTE]

i don't swap wheels often but when i do i just swap the cassette to the new wheel. but with the proper tools it takes about 2 min to do this.

Hi guys , i used the barrel adjuster and other options but nothing works.
I made an accurate analisys on the cassette and other parts measuring each single part with the caliber but everything was okay, until while i was moving the wheels i noticed that the training wheels have a little detail.
Basically with the racing wheelset when i close the skewers there is no gap and the frame will close perfectly to the wheel , but is not the same on the training wheels since the skewer make a strange way to close (basically let the frame flex for a fully clousure).
I just unscrew the bolts that holds the bearing and inserted a little spacer to keep the wheel at the same position of the racing wheels, i adjusted the derailleur with this new setup and now on the racing wheelset seems working properly, i just nmeed to test on ther others but seems that be the solution. (Maybe some spacers goone missed during the last bering change).

I hope you guys understand.......