I was told the front sproket is offset to match the larger rear wheel and is hard to find an engine the same.A good place to look is the japan bikes .They are way ahead of us on this.Has anyone ever put a different engine in a TW? BW350, Yamaha Warrior 350, DRZ400, Were some of my ideas. Is this possible?
Get after it and share the results with lots of pics! Something with a small v-twin would be great.
I can't remember anyone actually swapping an engine except the rare bird who owns a machine shop. The German member can set you up with a bigger piston and maybe a larger bore. Other than that, we are pretty much stuck with rejetting the carb, opening up the airbox, and sticking on an aftermarket muffler. The co-owner of my dealership showed me a picture of a prototype TW350 he tested a number of years ago. He said it was the perfect size engine for it. Never did make it to production. I am pretty sure we get the leftovers in the States anymore due to our nanny state govt. In Japan they have had the TW225 for a number of years but not a peep about them ever coming here. The same thing with the Land Rover Defender. the few that are here from the mid nineties fetch 40 to 60 grand. The cops use Defenders in England- I took a photo of a brand new silver one when I was on a visit. Land Rover says screw setting them up for the US- too many rules and regs.So the moral of the story is buy a bigger bike if you want a bigger engine, or move to Japan.
It seemed to me, that you could pick a larger engine that would fit into a slightly modified TW frame then have a machinist fabricate a primary shaft extension. Then you, or a machinist/welder would have to fabricate a bearing carrier for the extended primary shaft.
I work for a company that has a number of machinists and real high-tech CNC stuff. I recently asked a question regarding a primary shaft extender. They suggested all the O.D. work would be very straight forward (getting splines for a sprocket). It seems getting the I.D. splines to slip over the stock primary shaft (on whatever engine) require a much more time consumeing process called broaching.
It seems there are companies that specialize in "Broaching". If I were allowed a guess, I think you could get a shaft extension for an appropriate 'donor' engine fabricated for $500.
In my opinion, here is the strange thing about the TW. It is a unique, but 'cheap' bike. Yet most of us want to save even more money by buying used. In my opinion, and I bought new; the TW presents not much more than a low seat height and a couple of fat tires that offer (generally) better traction and balance.
I am all in favor of mods, as I have done a few. When it comes to bigger engines, and better suspensions, I would be inclined to say, "buy a better/bigger bike".
Like the Honda CT 90/110 (I've had one of each), the TW is set for a niche market that has recently been very much expanded by the Internet, Chopper Charles and another fellow who's name escapes me right now ( I purchased my bike because of his endorsement}. Mod away and enjoy, but the TW is not a "silk purse", I would be inclined to say a "Sows ear". Gerry
How about Yamaha XT350 engine? How much bigger would it be (lenght)? 6-speed and 27 hp. Sounds perfect for TW.