'20 RXB250L - NC250 Motor Swap [Build Thread]

[Ursa_Adv]

Originally Posted by ExMxer

That looks great! As far as your frame issue with your valve adjust, could it be possible to have two new tubes contructed that attach to the upper spine? I don’t know the trouble you are willing to go to, but having two “shorter” rails connected to the spine would still maintain a solid structure, but giving you room to adjust your valves without removing the back half of your machine. Just a silly idea, this swap reminders me of a 2 stroke swap I helped a friend on years ago. Your work looks really good, hang in there!

Not a silly idea at all. As I was sitting there looking at it, I had the same thought. Like how could we "redo" these pipes back here. I, of course, rabbit holed into "Why don't I just make a new a frame?" That was my "too far" moment. lol.

As the goal for the swap was to use the stock frame, I am going to see what my fabricator says about options. I need to take the frame up there to have them plot out my engine mount situation, which will involve hauling the motor up there too, so we'll see.

I have a back-up option in the wings, if I really need it, but I'm trying to stick to the original goal of putting more power into my RXB. If I start swapping frames we get into that philosophical arguments of "is a thing still a thing if you take away all the parts", "cost vs. effort", etc.