Are 944 ST2 cylinders a bolt on replacement for the 907?

They say so, even if some little fix is needed.
If I well remember, the RPMs counter and a few little things.
Ciao

Yes. The ST2 (94mm) cylinders and pistons are a bolt on deal for the 907 or 906.

The stock 906/907 cylinder can be safely bored and plated to 95mm which makes a 966cc. Pistal pistons are available from BCM or Kaemna

96mm (984) cylinders for the oil cooled motors can be easily modified to work on a water cooled motor. But you do need to bore the cases to fit those cylinders.

Would anyone know if it is worth the trouble of adding the 944 top end as far as a gain in power. The bike has Staintunes and an eprom for the slip ons. Would it need to be remapped? It runs a little on the rich side as it is now.

You'll get a small push in HP and a nice bump in the torque. You can also add some 944 high compression pistons 11:1 or so and make an even better gain. A power commander (and dyno) would probably help with the fuelling.

I put a 1080 kit with 11:5 to one pistons in my Multi and the change was really impressive. 89 RWP and 79 Ft. Lbs of torque.

ST2 heads are bolt-on except you have to make a tunnel f the rev counter mechanism.
I have done it, works well.

Gert, Do U have only ST2 heads, or also sylinders with 944 cc capacity?

There have been a lot of ST2 parts on ebay of late,cylinders are cheap, heads are cheap, cams cost more than the other parts combined

Ist necessary to use the 944 heads with the 944 cylinders, or can the 907 heads be reused? Would they make a noticable performance?

Preston

More cc, more power .... Also cams are very critical for reach better torque curve...

I have the 907 cyls w the ST2 heads.