350X 400EX Transplant Build!

[DohcBikes]

Now you guys are seeing why I kept talking myself out of the EX conversion and went strait to the 450.

No, I don't really see why. Not tough at all to use the frame for a tank. Several Honda bikes use this method.

[Matt85'350x]

I'm open to using the frame, I have to do the math to figure out how much volume it could hold. Reason I haven't considered it heavily is because phase 2 of this build will be to do a big bore kit on the engine. When I looked at engine mods for the 400 it seems added oil capacity is popular to assist in cooling. Don't want cooling to be an issue in the future. Without doing the math it seems the frame would be on the shallow side of the pool but adding an external tank could add up to a full extra quarter of oil. Maybe I'm thinking wrong about the capacity but this is what I've concluded based on the digging I've done. I'll go take some measurements and see just how much oil it could hold in the frame.

[DohcBikes]

But adding a cooler, anywhere, will also add capacity. The backbone and downtube are pretty large, it's a good enough system for an xr650. I agree with doing the math to know the exact capacity. Xr650 capacity is shy of two quarts.

[Jmoozy27]

But adding a cooler, anywhere, will also add capacity. The backbone and downtube are pretty large, it's a good enough system for an xr650. I agree with doing the math to know the exact capacity. Xr650 capacity is shy of two quarts.

Oil cooler is definitely the way to go. A stock 650l without the cooler runs too hot for comfort IMO. For peace of mind I added a small cooler which did not increase capacity much but I did see reduction in oil temp by about 15* give or take. I would go with a bigger cooler on your build. Possibly a Lockhart from an older harley or one from a xr400 which would be fairly simple to install but aren't always easy to find.

[DohcBikes]

It`s worn out technology ..... why does my little two fiddy blow the doors off a 700X ?.......and den the frame`s weak ? No offense to the op but .......it`s alot for a little gain .....put a Blaster motor in it !

Reverse and electric start will be worth it. Not to mention aftermarket support. If he goes with a 440 kit it will blow the doors off of a lot of shlt. Ever ridden a 400ex with a hi comp big bore? No? Then you don't know what you're talking about.

[DohcBikes]

There are 440ex's out there that will hit 100mph. Does your R do 100mph? Didn't think so. What was that you we're saying, about humility?

[Matt85'350x]

I didn't share my build for approval, just thought some people would like to see it. I now appreciate more all of the builds on this site. It really takes effort to take detailed pictures and explain everything in a way that could be understood. Between resizing the pics, putting them in order and explaining the process it really is a pain. It's a nice way to document the build while sharing my experience with others. No more pics until Monday, I didn't bring my computer home.

[RIDE-RED 250r]

Well, you guys beat me to the punch to suggest adding a second oil cooler for more capacity and better cooling. Also, while I was not aware of the XR bikes running oil in the frame (not as familiar with the bike side of things) I do know that TPC uses the frame for oil on some of their builds.

Also Bob Marlin, pretty sure the 450's use an oil tank as well. Still not seeing the advantage of the 450 over the 400, at least in terms of putting the conversion together with less hassle... Unless you went kick-start and eliminated the need to mount a battery.... But then you need to mount radiators for the liquid cooled 450 mill... To-may-to/To-mah-to

And yes, 440's can be quite nasty and would be one hell of a bad to the bone trike. At one time I owned a Suzuki Z400 with a 440 kit and the wife had a stock Z400.. The difference between the two was stark. I have ridden a 400ex owned by my brother in law that is set up with a Wiseco 416 overbore piston, cam and full exhaust right after riding a bone stock 400ex.. Not as big a difference as between the Z400 and Z440, but still quite impressive for some simple mods.

I'm still diggin' this build! Just make sure that when you 440 it, keep it well fed!

[350for350]

Hey Matt. Don't listen to what others say, do it for you! I'm enjoying this build. You're right, there's A LOT of hop up parts out there for the 400ex.

[userj8670]

The 400ex has an external oil tank. The oil is pumped into the engine. Not the only engine to do this.

Thanks for the reply! I am very intrigued - what would the advantages be of having the oil pumped in versus having it in the crankcase? This is something new to me lol.

Keep up the great work- I love what your doing!

[BOB MARLIN]

I think its a great build. Just have some things to decide what to do with. Just that when I was looking at possibly taking on the same project I had the choice of converting one my of 350x's that needs a rebuild, to a 400ex motor, or building a 450 trike. Either one is going to take a donor for the engine and a donor for the rest of the stuff and some fab work. Both have E start, one would have reverse. One will have mid 20's for hp. One would have mid 40's for hp. So for me I went with the way that had the most upside.

As far as not being able to the advantages of the 450 trike over the 400, double the horsepower is a big one for me.
And yes you are right the 450 has the oil in the frame. But its already there. So I didn't have to try to weld the frame up to do it, or find some where to mount a tank.
And yes you are right again, the 450 is water cooled. But its already there. I don't have to make room for rads. It already has them.

I'm not saying that the ex conversion isn't worth it. I actually like it and still might do one . I still have the tired 350x and the 400ex quad . That's why I am interested in this build. I just wanted to ask him what he was expecting to get out of it because Iv'e already
done the home work on it. I wanted to do something to gain on the performance side of it and for a couple hp it just wasn't worth it to me. He is doing it for a different reason witch he has listed, wich makes it a good option for some one looking for those things.

[RIDE-RED 250r]

I see where you're coming from now Bob, makes sense. Sounds like you are looking to convert a 450r bike then? I misunderstood you and was thinking you were looking to transplant a 450 mill into a 350x chassis.

Are you doing your conversion yourself or having TPC or JTS Customs do it?

[oscarmayer]

first off, AWESOME Freak in build sir!!!!!!!! LOVE IT!!!!!!!!!!
ok on the frame downtube. if you cap the top and bottom off and weld a tube to it to move oil to the top for delivery and use the bottom and put a fitting to hook to the motor you have a closed system, then weld in a small filler net that comes out in front of the fuel tank and up near the bars. this will give you a place to oil fresh out. don't forget to put a oil sight in the tube someplace. it will hose 1.23QT of oil per measurements.
on a side note, i would take a half pipe of chromoly that runs the length of the 350x down tube and weld it tot he frame, fitting it correctly over the old factory tube for extra support and protection against rocks and punctures. (so on the bottom side. make it like .195" so it is decently thick.

good luck sir!!! keep us posted!!!!

[Matt85'350x]

A 450 trike is not off the table for me, I'm just doing this first. Who says I can't have 350x hybrid and a 450?

And my investment will not be shared, only the build details. Financial reasoning goes out the window when you start talking about custom trikes. If you want the most speed for the least money get a bike and leave it as is. It never makes sense to chop up a bike or a quad if you just want speed for less money. A hybrid trike is definitely moreexpensive than just keeping the machine as it was intended.

[Matt85'350x]

As far as getting the engine in the frame, this is the only frame mod I've had to do. Before:



After:



The tip of the mount would just barely contact the engine. In the long run I was worried about an indent developing in the case so I added just a little bit of clearance.