I was curious to know how similiar a 1980 dt 125 and a 1979 dt 175s engines are and wanted to see if there parts were interchangeable. And also know if any of the electronics are the same like the coil or CDI.

I was curious to know how similiar a 1980 dt 125 and a 1979 dt 175s engines are and wanted to see if there parts were interchangeable. And also know if any of the electronics are the same like the coil or CDI.

Pretty much the same but there will be the obvious differences, Barrel, Head, piston, carb. As for the ignition sys if you compare part numbers between 125 and 175, that would be the best indication.

Pretty much the same but there will be the obvious differences, Barrel, Head, piston, carb. As for the ignition sys if you compare part numbers between 125 and 175, that would be the best indication.

So would the 175 cylinder be able to fit my lower end if I used the carb and everything off of it

I expect so yes, I will try to find out more.

So would the 175 cylinder be able to fit my lower end if I used the carb and everything off of it

Basically yes the stroke is the same, the barrel and piston is a straight swap. There are two extra studs in the barrel for the head on the 175 so you will need the coresponding cyl head as well. Dont know about the exhaust, prob a good idea to carry the 175 pipe over as well if you can as it may be a little different inside.

The carb will be needed as well, it is the same size and type (Mikuni VM24SS) but the jetting is different.

There are some minor differences in the advance range on the cdi settings but its only a degree or so one way or the other.

Even all the gear ratio's are the same, even the the final drive. Although the clutch has an extra friction plate in the 175.

Hope this helps, the bikes are pretty much identical in most every respect save for cc.

Basically yes the stroke is the same, the barrel and piston is a straight swap. There are two extra studs in the barrel for the head on the 175 so you will need the coresponding cyl head as well. Dont know about the exhaust, prob a good idea to carry the 175 pipe over as well if you can as it may be a little different inside.

The carb will be needed as well, it is the same size and type (Mikuni VM24SS) but the jetting is different.

There are some minor differences in the advance range on the cdi settings but its only a degree or so one way or the other.

Even all the gear ratio's are the same, even the the final drive. Although the clutch has an extra friction plate in the 175.

Hope this helps, the bikes are pretty much identical in most every respect save for cc.

Ok thanks that is alot of help because a friend of mine has the 175 that is in mint condition but the casting of the lower end is wore out where the crank shaft bearing goes and I was thinking about putting my stuff on that bike but it doesnt have a title so i figured it would be easier to put his stuff on my bike