Gregostini

I had a few yamaha YZs in my teenage years and into my 20s, 80cc 125cc and 250cc. Then the absolute laugh riot KTM380EXC, that thing would wheelie pretty much anytime, in any gear. Later on I put motard wheels on it. Shame I had to sell it a few years back. I still have my SZR660 track bike which doesn't get used enough, someday I'll find more time for it hopefully.

Finally it's all done. I had a baseline dyno run done last month with the standard headers, two brothers slip on, pipercross filter and rapidbike racing module. Pictures below of header before and after installation. All looks pretty well built to me, inside and out. It's also turning a nice gold colour now it's had a bit of heat through it. I discovered that the pair system was still pulling air through with some nice flames coming out on overrun, see the first video. I've since blocked the tubing for it with a marble to eliminate this until I fit some block off plates later. The second video clip was today on the dyno, unfortunately my phone didn't capture the sound very well once the revs rose. All in all I am pretty happy with the purchase, and bearing in mind that I have done very little mileage for the auto tune to do it's thing, I am hoping to end up with modest gains or at least no losses through the lower and midrange with the bonus of those few extra peak hp that carry all the way to redline. VID20210607173949.mp4 VID20210702092553.mp4

Yes, I had seen that, those are their fifth gen headers which for some reason have the cylinders paired differently to the standard exhaust. It occurs to me that this would send bad information to the ecu for fueling compensation, that's why I didn't want to go with those ones. This one, which I only found for the first time yesterday has the cylinders paired correctly and the o2 sensors in a more useful position.

So this has just appeared. I had been following the US header build thread (well out of my price range though), and looking at the other options had more or less decided to stick with the originals. Found it while browsing in a reasonably intoxicated state, and my drunken self decided to go ahead and order it there and then. $630aud delivered. I have a rapidbike racing unit and two brothers slip on fitted, and a pipercross air filter on the way. I will post my thoughts on my drunken selfs' wisdom at a later date.