Ye Olde Rd400

[SONICJK]

Grabbed this on cl yesterday afternoon for 350 big ones.

As soon as I got it home disassembly started due to a locked engine.
I found this under the seat

And after a couple hours of disassembly, a couple gallons of purple power here she sits.

I honed the cylinders and I think they are good to go.
The crank feels suspect so I soaked it in some degreaser and now it's soaking in a bucket of new oil. I am hopeful it's going to be turn out okay.

The plan for this one is a racer essentially. Stripped down to the basics and fast.

 

[VonYinzer]

Nice. You know Brad and I have a little RD stash at his place, so hit me up if we can help. Also, if you can swing it... Rebuild the crank.

 

[stroker crazy]

Good find!

Are you going to run the Newtronic ignition unit?

Crazy

 

[SONICJK]

Yezzir I am well aware haha.
I probably need to rebuild the crank but this is low budget at the moment. Want to get it up and running.
Money is going toward the SR currently.
There will probably be a money build on this later on down the road.


This bike basically completes my collection of all the bikes I have wanted forever.
CB400F
SR500
RD400

Damn. Now I have to find new bikes to drool over.

 

[TijmenK]

Cool! Will be keeping an eye on this thread to see what a performance focused project looks like, I read Sonreir's "Doing it right" in the engines sub-forum to get a basic idea of what needs to be done but it's useful to see an example too.

 

[2_DONE_THE_TON]

AW: Ye Olde Rd400

sonic i'm sooooo in.
seeing doing an RD right is better than good.


Gesendet von meinem GT-I9000 mit Tapatalk 2

 

[SONICJK]

Cool! Will be keeping an eye on this thread to see what a performance focused project looks like, I read Sonreir's "Doing it right" in the engines sub-forum to get a basic idea of what needs to be done but it's useful to see an example too.

It may be a minute before I get to the performance stuff
Plan at the moment is to get it running an rideable so I can get a good baseline.
From there ill start tweaking. Chambers, intake, porting, weight loss, suspension, etc

 

[TijmenK]

It may be a minute before I get to the performance stuff
Plan at the moment is to get it running an rideable so I can get a good baseline.
From there ill start tweaking. Chambers, intake, porting, weight loss, suspension, etc

Heh, it will be a minute or two before I've got the basics down and got my bike running properly. And in the meantime I'll entertain myself with fiberglassing and upholstering a proper seat from this thing, should be a good start for weight loss too.

 

[SONICJK]

Just a side note to this.
I have always used simple green to degrease parts. It works okay.
I have used purple power on this one and holy hell it's amazing.

I dunked the heads with 37 years of nasty grease and grime in the vat, and literally within 2 seconds they were brand new grease free.

 

[bradj]

Now you just have to get rid of the dead weight in your collection and you will be all set

 

[CarbsAndCylinders]

I never seem to get deals like this, congrats!

 

[SONICJK]

Now you just have to get rid of the dead weight in your collection and you will be all set

Ill put my 400f against any of your bikes TODAY.
But only because you'd have to push them

 

[Mr_Dunev]

Hells yeah I'm in! Love me some RD's

 

[SONICJK]

Carbs were gross

So some disassembly and some soda later:

Good as new.

Here's where we stand as of now

Ready for new rings and seals then assembly.

Quick rebuild to running here then later tear it down and make it all pretty

 

[mikeinnh]

Great bikes! I had a lot of fun with mine. A '76 model, I bought it new in April '77. Rode it, wrecked it, revived, it raced it, rebuilt it, then finally traded it to my son a couple of years ago, so it's still in the family.

 

[clem]

Why was the engine locked up? Was it the top or bottom? I'd do like mike said and rebuild the crank. Would be about $500 but you wouldn't have to tear back into the bottom end again. Seems futile to do it twice especially if you think that the crank is suspect. At least check the play in the rods. Great score though, that's a damn good price.

 

[SONICJK]

It was locked from the pistons in the cylinders.
All the crank bearings now rotate freely.
Ill measure the play in the rods for sure.
And tearing it down again is going to happen anyway. I don't mis doing it. I can have the motor pulled and the cases split in a half hour. This engine is just stupid simple.

 

[VonYinzer]

Valves and cam shafts are for suckers

 

[SONICJK]

Valves and cam shafts are for suckers

Agreed man.
I didn't even bother with a manual and I had the engine stripped to what you see in the pictures in an hour the first time.
Lovin' it

 

[clem]

I agree it is a simple task. I just said screw it and sent my crank off that way it was one less thing to deal with later.

.........
Do you have it back together yet? I mean it's been days since it's been torn down. Ha!