rainman
Member
That front rotary valve Ital was a real beast, though it made things more complicated. I like simple things, that's why I love air cooled direct drive reeds.
vortex vr95
- Thread starter ttownwideglider
- Start date
That front rotary valve Ital was a real beast, though it made things more complicated. I like simple things, that's why I love air cooled direct drive reeds.
Ted Hamilton
Helmet Painter / Racer
OldAsDirt had a couple front rotary Itals....don't know if he still does. So, what's the verdict on the VR95, ttwg? Did you get it?
FA and FSA were rotary only at first, then reed and rotary when W/C came in for the 2001 homologation. Reed became the tour de force towards the end alright, but the class was never reed only.
ICA however has always been a reed class.
Ive read a lot people saying the SV21 was dominant, but to be honest I never saw that. It was a strong contender no doubt, but the the VR98 was just as quick anytime I saw them on track at world or national level.
ICA however has always been a reed class.
Ive read a lot people saying the SV21 was dominant, but to be honest I never saw that. It was a strong contender no doubt, but the the VR98 was just as quick anytime I saw them on track at world or national level.
rainman
Member
Good explanation here. I will add that FA and FSA replaced the 135 cc class as the fastest FIA/CIK class. Nevertheless even if FSA was the fastest non shifter class and at many tracks even faster than the old ICC shifters, fIA/CIK would still only consider ICA as the official World Championship class so that in many listings the JICA and FSA winners are not listed as World Champions.
tom rickard
New member
When the reeds and rotaries were combined in CiK classes, they were heavily restricted to 24mm carbs, this leveled the playing field between them, but significantly slowed the FSA motors from the speeds they achieved when they were able to run a 29mm slide carb. If carb size is unrestricted, expect the rotary to be significantly faster.
I have done back to back testing of a strong 100cc IAME RLtop reedjet with an IBEA L5 carb, and the last of the FSA spec MRC RSV2 rotaries with a 29mm IBEA slide.
Most of the top guns where I race have played with the reedblock of the reedjet and tried bigger carbs, but it doesn't make a great deal of difference.. On the other hand if I put the L5 on the MRC, it is slower than the reedjet.
I have done back to back testing of a strong 100cc IAME RLtop reedjet with an IBEA L5 carb, and the last of the FSA spec MRC RSV2 rotaries with a 29mm IBEA slide.
Most of the top guns where I race have played with the reedblock of the reedjet and tried bigger carbs, but it doesn't make a great deal of difference.. On the other hand if I put the L5 on the MRC, it is slower than the reedjet.
rainman
Member
Agree on this. Using bigger carbs made these rotaries monsters. But my rotary Ital on a 24 EC Tillotson seems to be faster than most reeds I have tried from same years too.
The rotaries won everything in FA until around 2003 when reed development really took off. Also note that the rules in ICA limited port timing compared to FA, so an FA spec reed valve engine is more powerful than the same engine built to the ICA rules. Point being: the late model liquid cooled FA spec reeds are nasty, but as far as the earlier models go, rotaries are generally more powerful than their sister reed models all things being equal.