[toomanytoys2]

For the muffler, I will be going with one from a Yamaha WR250F dirt bike. Those bikes were rated at around 30HP, so it should flow good for this motor, and be really quiet. If I feel like it is too restrictive, there is an internal baffle that is easy to remove, yet doesn’t increase the noise that much.

When I tried to install my carb into the stock intake manifold, I ran into two problems. 1st the throat of the carb was too big. 2nd the angle of the manifold caused the carb to hit the coolant connections, so time to make a new manifold. So scrounging through my metal scraps I found some good flat stock, and some pipe that had the same ID as the carb throat. So with a hole saw, pipe cutter and welder, I fabbed up a new intake manifold. Don’t look too close at my welds, 80% of my welding, I do outside, so I use a modified Harbor Freight flux core welder. To join the carb and the intake manifold, I am using a piece of radiator hose. However, the output side of the carb is a little too large for my taste, so I chucked the carb in the lathe to reduce its size. However, since the intake side and the output side are offset, I had to use my 4-jaw chuck to get it square. For the air cleaner, I had to use a 90 degree elbow for clearance, and I also had to flip the elbow around to match the OD of the carbs intake. To mate the air cleaner to the elbow, I got a short piece of exhaust tubing that they can both clamp to.

You may be wondering why I am doing all of this external stuff first, especially on a worn out engine. That is because I am waiting on a cam. Tom at SYC Powersports is grinding a cam for me. I will be kind of a guinea pig for this new cam, so I am trying to get everything else done before it comes in, and I tear the engine down. More to come…..