Do the YT175 and YT125 engines use the same carbs/exhaust?

[bobotech]

I have a YT125 that runs fine but I would not mind more power. I found a YT175 engine complete for sale near me. Its the complete engine minus the exhaust pipe and carb. Can I use my 125 carb and pipe on the 175 engine?

And is the 175 to 125 engine swap a bolt in affair?

[Vealmonkey]

No, they use different carbs. The even use different carbs on the 80-81 yt125 and the 82 and later yt125 and I think there maybe different jetting on the 82 and later carbs in different years as well. The 125 and 175 factory pipes are way different. Most aftermarket companies had different pipes for the 125 and 175. A few companies used the same pipe for both. The 125 and the 175 have the same bolt holes in each engine so it's a simply bolt in swap. The 80 and 81 yt125 had different frames and big differences in the engine pieces, and the 82 and later yt125 and yt175 were really close. There are differences in the 125 and 175 clutch and even differences between the 82 and 83 yt175 clutch. You really have to do your homework and take your time comparing the differences between all the yt trikes.

[bobotech]

Wow.

So I'm getting really confused now. LOL

Basically I have an 80 YT125 and I just bought a 85 YT125 (mainly for the valid title but has seized engine). I also found someone selling an 84 YT175 engine but he has no carb for it or pipe. I was going to see about putting the YT175 engine in place of the seized YT125 engine. I was going to put the suspension fork from my 125 onto the 85 125 when I got the 175 engine in place.

The big thing that is the stickler is the lack of a carb. How much would a YT175 engine be worth that turns over and has compression but is otherwise unknown if it runs? And can I mod the 125 carb to work with bigger jets or something?

[scottytohotty48]

I got a 175 carb and pipe plus other parts. Pm me

[Vealmonkey]

Well, let's really confuse you. I know the fuel tank on the yt175 is twice the size of the 80-81 yt125, not sure about the later 125s though. I'm not sure if you can put big enough jets in the 125 carb, but the 125 carb won't flow near as much air as it's a small diameter carb opening. So even adding bigger jets to the 125 carb would probably be bad news. Then you have the yt175 which has a vaccuum operated fuel pump that the 80-81 definitely doesn't have and I'm not sure if the later 125s have either. I also know the 175s had an air inlet in the fuel tank cover that I'm not sure the later 125s have. So there are lots of differences. But you have the later 125 to look at and I've never really seen a later 125. The shift lever mechanism on the 80-81 is way different from the 175. I would think if you have the later 125 trike, that would be the trike to put the 175 in as it should be more like the 175 trike. Don't even mod the 80-81 trike as there are just too many differences. The rear bearing carrier on the 80-81 trike is different than the 82 and later trikes. Put your 125 trikes side by side and start comparing, you'll be amazed at the differences.

[bobotech]

I will do that then, just keep my 80 125 intact as a 125.

What would be a reasonable price to pay for the 175 engine with no carb/pipe and unknown history?

[Vealmonkey]

To me it wouldn't be worth more than $100, maybe even less. It's an unproven engine and if it isn't running for you to see, who knows what is wrong with it.

[bobotech]

Well I bought the engine tonight for 75. It is complete and came with the CDI box and the fuel pump but no carb or pipe. It is quite clean and pulling on the cord seems like it has good compression so I figured what the heck.

I have to get my 85 YT125 home now so I can start stripping it down and transplanting the engine over.