YZ400 pros and cons

[JWjite]

I have recently picked up a 1978 YZ400 motor,rear bracket,CDI,Reeds,Carb and boot I have a spair blaster with no motor and I am thinking maybe I want to combine the two. I was told not to do this by another person and I am sure more people would say the same but I just want to get opinions from the rest of you. I am some what handy and do have a welder and most any other tool I may need to do this I just dont want to put this thing in my spair blaster and regret it in the end. What can I expect out of this combo? what would those who have done this build have done differently or what input can you give me to avoid some of the things you may of had trouble with?

 

[CARNZ]

talk to Paulie B, he has the YZ400 swap

 

[Paulie B]

Cons:
Rebuilding the whole motor because it's an antique.
Trying to start it.
The work involved in making the mounts.
Making a pipe that works (very important).

 

[JWjite]

What about the pros? I would have thought you would have alot of them?

 

[Paulie B]

Pro's? Well you can figure that out lol
Having a motor twice the size as the stocker
Having double the torque.
Potential to double the stock 38hp
Ride all day in 3rd gear
Easy wheelies in all the gears

 

[Blaaster]

I realise that this is not Blaster related but it may be of help.

I have an Yam IT400 fitted in a Suzi 250 frame, and the pros are ^^^^^.

My only gripe is that that I am continually having to repair the frame as it is continually breaking.

 

[Paulie B]

I realise that this is not Blaster related but it may be of help.

I have an Yam IT400 fitted in a Suzi 250 frame, and the pros are ^^^^^.

My only gripe is that that I am continually having to repair the frame as it is continually breaking.

Thanks for bringing that up.
To the OP be sure to make your motors mounts heavy duty and solid.
Beef up the area around where they will be bolted or welded and gusset the frame. (I didn't and there are cracks there now).
Do that and the swap should be well worth it. I've never looked back on my 400 hybrid but I wish I had gusseted the frame and beefed up the mounts.
Live and learn, thanks to this forum you can now skip the 'buying a new frame after a couple years lesson' if you choose to.

 

[JWjite]

I think I am going to put the blaster stuff on the back burner and finish my s10 build. My garage is way over full and I dont have the room to start working on this at the moment.