I decided to do a bit of upkeep, so went to replace the spark plug and check valve lash. The valve lash was off (loose) so fixed that up to 0.10mm in / 0.15mm out per the workshop manual specs. I did a quick test ride and it seemed to run a bit better. I went out later and it had almost no power at all.
Right now, it idles great, but occasionally will stall. If I give it throttle, it may stall or hesitate, or I get good rev, but no power to the wheels (almost no movement when on the ground).
Here is what I've done:
- Re-checked the valve lash (probably 8 times at this point), made sure it was TDC on both flywheel (second notch) and cam markings (line). The markings do seem correct. I unfortunately did not keep the original lash values.
- Tried both slightly tighter and slightly looser valve lash with no success
- Swapped in the old spark plug and checked gap (0.75 on the new, 0.9 on the old)
- Completely cleaned the carburetor (idle jet was clogged but everything else seemed fine)
- Cleaned and re-oiled the air filters
- Replaced fuel and vacuum lines (they were looking a bit old)
- Checked for leaks as best I could
- Oil replaced and filter cleaned
I don't have the equipment to check compression. Does anyone have an idea of where I could look next?
Video here (this is about a minute after cold): https://1drv.ms/v/s!Al3CQyGP5qmKnMEEVtXZBSnLwDcTuQ?e=iNGbns