I recently bought a 1971 ct 175. I got it running, but can't seem to get the carburator settings right. It will run and idle, but seems to die right away when I give it gas. The fuel filter is clear. The spark is good. The air cleaner is fresh. Any suggestions?
Timing is a possibility. The reason I ask about difficulty in starting is that gives some indication of the general mechanical condition of the bike, that is, reasonable compression and carburation, etc. Let us know what else you find. [img]/ubbthreads/images/graemlins/cool.gif[/img]
Had this problem with several Yamaha's in both the DT and CT series models. Mikuni should be set at: slide needle in center groove, low end air screw 1 1/2 turns out. Make sure no vacuum leaks on carb intake or cyl. base gasket. After all that is checked it can be only one thing and that is the crank seals inside the case. One on each side of the crank shaft. With the right tool (which you can make yourself) you can pull and replace these without splitting the cases. With these seals bad you cannot create vacuum in the bottom end, cannot develop pressure to force air fuel mixture up to the combustion chamber. Hope this helps!!