Anyone got any answers to why ive done this to 3 cranks in 2 Sirio 21 kanai evo 2 engines , they were all running fine doing 5 min races and out off the blue ceasure. Even the STI crank did the exact same on the right. Ive persisted in running them for they have shown heaps off grunt, but now im turned off.

there must be something in your crank case thats binding maybe check bearings or if there is any burs inside your case becuase if u look they have all broken in the same spot
i have never ever broken a crank before and i run mine pretty lean lol

Bearings

I have several mates that have had kanai sirios and while they all say they are stupid fast they have all had breakages, bearings, cranks. I believe that sirio has or had a quality problem, however this is just my opinion. Having said that i have had 2 Evo 3 (one an STI) .12's have major bearing failures within 4 ltrs, so bad that i had to replace, bearings, piston/liner and head buttons, so this kinda backs up my opinion.

Worn rear bearings will cause the cranks to snap in this fashion - I ran Sirio for 18 months without a single failure, some of the guys I race with snapped crank after crank.

The only difference - I always checked the bearings and replaced them as soon as I felt any free play.


Hope this helps !

4 litres is a fair bit, before my engines started to come with ceramic bearings i used to change my 8th scale bearings every hour

All problems have been rectified with the CL7R now, bearings are good and the whole engine is reliable and insanely fast now

sirio motors are great now there are very reliable and after seeing simons go at the nationals i would beleave what he says i might even try them

Yeah granted 4 ltrs of fuel under race conditions is alot, but these were brand new engines, and the 4 ltrs included 2 ltrs of running in, these engines were not raced tuned at all. Anyway i am over it just wanted to post my findings. cheers