Although I've been lurking here for a 2-3 years, I haven't posted much. So as a relative newbie feel free to point out my mistakes.
RichardSIA wrote:
Are you saying it uses the same rotation at the output as an FJR 1300?
If so I may have to look for one too.
I think the FJR 1300 and the Rocket 3 both have the driveshaft on the left side which would mean they both rotate in the same (wrong) direction.
horizenjob wrote:
It's about the same weight as a Ford Duratec with a T5 transmission and probably a little more delicate. The Duratec comes in several flavors. Hmm, now I'm remembering that bellhousings are an issue. It's something else to look at though. The Duratec is much lighter than the small engines that can make big power on Turbos.
If you want the Triumph though, go for it. Look carefully at the transmission and final drive ratios...
I haven't been able to find the actual wt. of a Rocket 3 engine. If anyone has weighed one I'd love to know. What I have done is to research the wt. of 6 other large bike engines, and then divide that by the dry wt. of the bike. By averaging them I came up with .332 or engine weight being 33.2% of dry bike wt. This x 736# for the Rocket 3 Roadster = 244# plus about 10# for the reversing gear box = 254#. I'm sure this is just a ballpark figure. The Duratec I think comes in at about 275# ready to run with starter, flywheel, and pressure plate. To that you need to add a bell housing (15-20#) and T5 trans. (about 75#) = 370# total. The plus side to the Duratec is that my wife has an Ecoboost 2.0 version sitting in her 2013 Escape, but I know she would have my number as soon as she hit the start button.
The other advantages to the Rocket 3 with the homemade gearbox is that it not only reverses the rotation and helps center the driveshaft, but also allows me to change drive ratios and adjust the vertical position of the driveshaft by rotating the gearbox mounting position around the Rocket 3's output shaft. This may allow me to lower the engine and CG since I don't have a large bellhousing/flywheel to deal with. Also I may be able to go with a narrower driveshaft tunnel without a trans. hanging off the engine, which would allow more pedal room and seat width (or maybe a narrower and lighter frame).
Another advantage at my age is that it's a lot easer to part out a doner bike than a car.
I haven't even decided on a frame design yet so I'm probably getting way ahead of myself here. I do appreciate the deep knowledge base here and look forward to more input.