Well I got my WO578 yesterday got my old ones off a disassembled.
But I have heat Demons and They WILL NOT FIT throttle side.
Looks like ill need to ream out the bars !!!

Lots of threads on hear about it !!
Who did it them selfs and what reamer did you use and where did you get it!!

Harborfreight sells a set fo 80.00
don't really want to spend that 4 1 time use

 

The w.o. 578 are smaller than stock?

Your TBW fits in there and the heat deamon should wrap right around the TBW assembly and push her in no?

 

Yes the throttle side is smaller inside!!

 

Did you clean the inside really good?

Not so sure I would want to make the bar any thinner that it already is.
maybe a phone call from em might help

 

These bars are thicker than a stock BAR
reamed out would be the same as a stock bar!!!