94 Accord vibration

Just replaced both CV shafts with new components. Now I have a slight vibration in second gear only. I can feel the vibration thru the gas pedal. This is on light or partial throttle only. WOT makes the vibration disappear as does coming up to speed? Suggestions? Thx.

An axle could be out of balance.

With drive shafts, I used to test the balance by putting a hose clamp around the middle of the shaft and driving it, to see if it changes the vibration. The off-center weight of the screw on the clamp acts just like a wheel weight, and you can clock it around in different positons to see what effect it has. Sometimes you can get rid of the vibe altogether this way. But if a short shaft like that is causing a noticeable vibration, the shaft may be slightly bent and will put a lot of stress on you gearbox output bearings, so I'd return it and get another halfshaft, if that's the problem.