93 Accord LX wagon w/ a slight shutter on acceleration

When I accelerate on my 93 Accord LX wagon it has a slight shutter between 2200 and 2400 RPM. My mechanic just changed the timing belt and some seals. Any ideals what’s causing the shudder? I’ve done a lot of maintenance on the car. Otherwise it runs fine. It’s a manual tranny and a lot of fun to drive.
Any ideas on the cause of the shudder, thanx in advance,