Hi all,  I'm looking at grabbing a little project bike and the old DTs seem to be a good way to go.  There's one available in great shape but it isn't running; seems to have been someone's project that they don't want to take any further.  The ad specifies it's a 125 with 175 head and piston, so sounds like maybe was rebored bigger and now doesn't go (apparently it will sometimes run briefly after a push-start but won't keep going or start by kickstart).  Anyone done this sort of mod to an engine?  What did you do to get it up and going afterward?

Bike allegedly has new carb, air filter, piston and rings...  So maybe something wasn't installed properly, or there's something the seller hasn't done with it?  I'm game for some head scratching and getting greasy, but not looking to throw money out on a lemon...

Don't know about that bike but swapping the carb (not vital), head, barrel and piston for 175 parts is a straight nut and bolt swap.

Im actually doing the opposite to my 175 so my daughter can do her test.

No special modification at all. Whatever its problems they will be no worse than any other 30 year old lucky dip.