2020 Honda Monkey and others
The Takegawa chart with the 27PS is on their latest Monkey brochures.The over pipe actually gives a reasonable clearance to the oil filler line and also the oil cooler lines.
For your throttle body, use a 34mm unless you are going to get it ported. A 34 is enough for a 5 axis or standard takegawa head. The 37 I have is overkill unless you are getting it ported.
The 15d cam is not much different to the 10d cam. Peak lift and duration is about the same, with the profile and lobe seperation being slightly different. If you really want a top performer, either send your 10d cam to Web Camshafts ($$$$) or send your 15d to DCR ($$). Both these companies have produced upgraded cams for both the takegawa and koso 4v heads. If you decide on the DCR, tell Dan to give you the same grind as Aaron.
I'd be very skeptical of the 27hp claims, since the 5 axis still has an anaemic exhaust port.
Yet, in the same box they include Grom parts brochures that show 23PS.
What I can say is their chart has been accurate so far regarding the power output on my 2V 181. If anything they are slightly under representing their numbers.
Hoping for the big gains.
Looking at their 10/10D versus 15/15D it does show much more high end capability with the 15D cam. It shows stable top end power all the way to 12.5k rpm.
The 10D tapering off slightly earlier and having a peak at high end versus the plateau of power in the 15D cam.
The 27PS chart I haven't seen online.
Maybe it is for their complete engine that has the dry clutch?