We gettin closer.. Now drag down your stock silencer and stick that thing on the stock nipple.. That is the only way we will know, absolutely / definitely, how the Yoshi is designed to interact with a header..

You should now have a little improvement in power levels and throttle responses - certainly below 7000 rpm - and a little more power 7k - 9k...

 

Yep. It runs much better now with the stock header. I'm not pulling wheelies, but there is a noticeable improvement throughout the rev range. I should maybe edit the first post in this thread.

 

Ok, great.. Now that you/we know the Yoshi nipple, please, if you can, get us a measurement on the stock silencer nipple. I am not able to do this..

While I am quite sure it will be the same, we don't know until we know.. Then I can add the Yoshi data to the Exhaust sticky.

 

Here is the measurement of the stock exhaust nipple. 32.05mm or 1.26in. A little larger than the Yoshimura, but darn close.

 

Ok .. that's it - we done..

Yoshi slipons are "stock header only" ..
Incompatible with performance headers..

I'll make the entry into the Exhaust choices Sticky..

Thanks Cormace..

 

Also, now you can get a FMF slipon for the PB and sell the Yoshi. Results will be a boost in power levels 6.5k rpm to 10.5k rpm, but with a loss of power levels below 6.5k rpm from what you have now..
What you have now is superior power off idle to about 7k RPM - after which your power levels will begin to drop off until, at 9k rpm, you are "done"..

 

Here is the beauty of your current situation:

With the dynojet PCFC, you will be able to quickly adjust your WOT( wide open throttle) fueling curve while on a dyno. This is all that is important.

You can adjust the low and mid ranges yourself to suit your preferences..

Create a relationship with a local dyno shop and you can quickly compare/contrast your exhaust components (if you acquire an FMF slipon for that PowerBomb) as well as lid-on vs lidless power curves..

I am thinking that once fueled correctly with a lidless airbox, your current setup (stock bike + Yoshi ) might be able to do 1st gear power wheelies (with some experimenting on the RPM point before snapping to WOT).. like the wheelie vid below on my signature line..

 

 

 

Kris250, above, has the most current knowledge and practical use of tuners and prepping an '18 for performance..