Tips and Mods
Raider Mod by Kurtz

This is a mod from Kurtz from Italy for Raiders to get a narrow gap without the risk of breaking the yoyo.

The stuff for 1 Kurtz Raider:

1 Yomega Raider
1 Thin Ball Bearing (From a Twister YoYo or a Spintastics Metric Bearing)

Little saw
2 sheets of sandpaper (n. 360 and n. 1000)
Screw cutting die (n. 3,5)

Open your Raider and take apart the original bearing and spacers.

Get a Twister Loops yoyo bearing with brass spacers. If you don't find this model of bearing, you could use a Spintastics Metric Bearing. The important thing is that the bearing must be thinner than the Yomegas. Twister Loops Bearings are about 1,8 mm (thickness).

Yomega Fireball and Twister Loops bearing with brass spacers.
Cut (possibly with a little saw) the yoyo axle. 1-1,5 mm of cutting should be enough. Cutting the yoyo axle (about 1-1,5 mm).
Take a screw cutting die (n. 3,5 should be good) and enlarge the screw by cutting on the axle of the yoyo. This enables the axle to penetrate deeper in the half, so you can narrow the yoyo gap, so enlarge it, until the gap is about 2- 2,5 mm. Make a longer cutting screw on the axle with cutting screw
Here you can see the difference between the original and the cutted axle. Difference of the Axle length
Sand the brass spacers on the bearing side, until they are even or a little bit under the starbursts. Don't sand too much, or the yoyo will be too responsive and the string will be embed between the bearing and the spacer. For sanding use first a medium sand paper (n. 360), then "polish" the sanded side of the spacers with n. 1000 (super-fine). Sanding the brass spacers on the bearing side with n.360 paper and polish with n. 1000 paper
This are the sanded spacers. The sanded brass spacers with bearing.
Put some white vaseline (as much as you desire) between spacers and the bearing and if you want between spacers and yoyo halves. Putting white vaseline on the spacers
Put the parts together, screw the halves until they are perfectly closed on the spacers (with no play).

Put on the string: maybe a thinner string is better.

The new gap vs. the old one

The result is a super looping yoyo, with still a good sleeper (this depends on how much vaseline you put into the spacers) and with thin strings also a good smoothness even on the trapeze.!