A few weeks back, after I mounted the engine, I try to install the exhaust system, but the end of exhaust pipe and muffler didn’t match. The tip-end is 5 inches away from the frame and the muffler.
I went online and discovered there are separate numbers for the engine heads and exhaust pipes for each of singles models, R24, 25, 26 and 27.
I realized I got an R27 exhaust pipe by mistake and order the correct for Zenaida (R26) and it’s been inside the box since then.
On the left the R27 exhaust on the right the R26. It's a huge difference.
The time came for a test ride and to install the exhaust system, but oh surprise.
The new R26 exhaust didn’t match either.
In order to make both exhaust pipe and muffler mouth align I need to incline, sideways, the pipe at the spigot 8 millimeters.
Something like this.
I placed the new pipe against the very old one and there is a difference. The old pipe was bent to run straight and parallel to the frame, while the original follows a different line.
Thread repair and/or wrong head?
15 years ago “Someone” offered to repair the threads and managed to burn the fins next to the spigot. Unfortunately I didn't know any better and didn't pay much attention to the work. He really did a terrible job.
Before touching the head I try to find an exhaust fabricator to bend the pipe or to modify it but I couldn’t find any local talent with the right set of dies or willing to cut and weld the pipe at the right angle.
Looking for answers I contacted the previous owner in Mexico. He remembered something to do with a twin head for a repair, but this happened more than 40 years ago and he couldn’t give me more specifics.
I found out the singles heads spigot have a 15 degree inclination versus the twins. You think the difference to align the pipe and muffler is more less 15 degrees?
Is this the wrong head or a bad repair or both?
I couldn’t find a mark or a part number, can you tell if it is a twin or single cylinder heads?
Repair (is possible?) or replace the head, what would you do?