Topic: CB400 Four to XR400 Four

[Pezz]

Oh, I picked up these XR650 forks as Im a little worried about the back-end out suspending the front end

[Pezz]

I spent most of the afternoon yesterday sorting out what I have to do to fit what in where.

The Husky pivot end is wider than the 400/4 by 7mm, and narrower than the 400/4 at the axle end by 30mm.

The rear wheel has a fair amount of spacing for the chain as can be seen below



The Husky measures 200mm at the axle.



The 400/4 measures 230mm. To fit the rear wheel I would have to remove 30mm or 15mm from each side which I cannot do with out fouling the rear sprocket



Think I will just have to cut and extend the CB400/4 swingarm 100mm. The add some bracing.

[Pezz]

As time is sliping away I decided I need to get a good look at the front ends of both bikes.

Stripped the CB first and unplugged a lot of wiring, its funny that you see something so simple and then you are reminded that the wiring is still to be sorted.

It all came apart pretty easily.



The XL on the crate ready.



I removed the Ball Race bearings and placed the XL forks in for a look.



As I thought, The stem is too short.So Off to the Steel Shop for some 4140 - 30mm bar stock. Dropped in for a quick chat with Laurie Alderton and pressed out the XL stem. Now I just have to work out the geometry and steering head bearing dimensions. The Standard 400 bottom bearing is 50mm OD with a 30mm ID. The top is a 48.5mm OD and 26mm ID. If I have to I can make up a few spacers to suit, just thing the 48.5mm OD might be the tough size to find. That being said you can buy a kit from the UK to update the bearing to Tapers on the 400/4.

[Terry in Australia]

Hey Pezz, why not just lengthen the steering stem? If you've got access to a lathe it's a piece of p1ss, just part it on the lathe and turn up a slug that's a tight "pressed in" fit into the stem, and weld it all up? I've done it on a couple of bikes now, and it's much easier than what you're planning? Cheers, Terry.

[Pezz]

G'day Terry

Never thought about that before Terry

Great Idea!!!

I will get too it 

[Pezz]

Well its been a busy weekend apart from the bike build.

After getting the XR stem pressed out, and with the suggestion of Terry above, extended the shaft 20mm to align the steering head bearing surfaces.

Process was quite simple, part the shaft in the lathe, face the edges, fabricate a spacer which would be pressed into the shaft, took 6 ton of pressure, machine a groove, then weld and machine down to 25mmOD,

I ordered some Taper roller bearing kit from a UK which should be here in a few days. The bottom bearing has an inside diameter of 30mm, the stem is 26mm. I will make a sleeved spacer to take up the 2mm ID and locate the bearing in the correct placement.



Once the front end is mounted I then need to lift the back of the bike to get the desired steering head angle.

Whilst waiting for that, I am progressing with the instruments and headlight. I want to run the CB400 headlight assembly.

The mounting will be pretty straight forward, but the idiot lights need a  new cover made to hold the coloured lenses in place. I will build this out of alloy plate and hand file into shape.




The Bearing, new camchain amd engine seals should be here by Wednesday, and that will allow a big leap forward.



Ever had a Brainfart??? You know when you do something you never thought you would do. Or buy something you never thought you would.


Well I had a beauty a few weeks back, bought a bike I didnt really need. Ebay is a terrible thing when ones imagination is left unchecked.

I sought the sage advice of tHE tREV (Advrider inmate) on my momentary lapse of reason. His response

You did what?

... Idiot...

I now own this:



This cost me $800 and I have justified it by calling it my backup plan if the 400 doesn't get finished. I suppose it will be more like punishment.
Oh it hasnt run for 5 years and has no air cleaners. As usual the photos do overstate the condition of the bike.

Well better get back to it.

[greasy j]

that things not so bad. no air cleaners could mean probs in the engine. looks cool, though.

[Pezz]

that things not so bad. no air cleaners could mean probs in the engine. looks cool, though.

It has been in a shed for 5 years, the old foam ones fell apart, It hasnt been run without air cleaners as far as I know.

It would run for a 3-4 minutes then stop. hope its just a blocked fuel tap. aparently rust in the tank is a little common on these old yammy's

[Pezz]

Well there was a little progress this weekend with the bottom end back together, need to get the rest of it completed as I am running out of time.


I was standing looking at the bare cases and wondering how this all came apart? It was a little daunting, but I took a lot of pictures and used the spare parts book and took little steps. It is a straight forward process, the gearbox just fell in, well sorta.


Sorry about the pictures, taken with the iPhone as I forgot the camera

[Pezz]

Well finally got the front end on. Fitted this little spacer



Then the rest basically fell into place. Mototrans popped in for a coffee and a play in the sandpit, Thanks Scott.
The fuel tank will be an issue as the forks hit the tank before reaching full lock. I will have to either move the 400 tank rearwards, fit the XL tank or another tank, but really cant get that done until the motor is back in the frame.



Scott removed the coils while I was on the phone and fitted up the XL250 Tank. I prefer the 400 tank myself.



Back to it, I have to buy some steel flat bar and angle to make some brackets

Well this weekend a mate, OldDog, arrived from sunny Cobar to pick up 'Cousin IT' the IT490 and we had a productive night punctuated with a few cleansing ales

Below is OldDog in the morning before his long trip home, looks a bit worse for wear, must be his breathing all that the polluted air



Well, with some encouragement from Bill, thanks old Mate, got the motor back together and back in the frame, Im only missing a few bolts, which is quite good.

I have to do another order of parts, hopefully locally.

The swing arm is being extended and I will have to chase that up on Monday. That is slowing progress to completion.

I will have to get a rear knobbie tyre organised and some chain, oil, plugs, air cleaner amoung a host of other parts. Plenty to still get done.

[Pezz]

Well there has been some progress!

Picked up the swingarm for Jason@sinergycnc.com.au he did a great job and can turn out great work on his collection of CNC Mills and Lathes etc. Thanks Jason :thumb



Slipped the swing arm onto the pivot and then grabbed the shocks and the eyes lined up perfectly
 


Inserted the rear wheel, which will be getting a nice little knobbie shortly, then jacked up the rear end and Mounted the Ohlins.



The frame is level and the static seat height is about 900mm



Its looks great, off to buy some bushings for the shocks and finish this sucker

[Industrial Rat400f Killer]

When can I take it for spin?

[Pezz]

When can I take it for spin?

When ever you come over this side of the Pacific 

[Pezz]

Well a lot has happened since my last Post

I finished the build, but the night before I departed on the Scrapheap Adventure Ride she locked solid. 

I have pulled the head off and there is oil there and looks fine, I need to go deeper.

It came up really well. Couple of issues were no turning lock once the XR forks were fitted. I bought a another rough tank and inserted some releiving dints but never had to use it. I am still thinking about where to from here. I will get it finished and running. Might build it into a sidecar for the ride next year . . . unsure really

[Industrial Rat400f Killer]

Sorry to hear you never got to run it, there's always next year.

[le_sterls]

This is the first time I've ever seen this build thread, and I must say, I'm impressed with what you've done to the bike. The thought of turning a road bike to a dirt bike has always amused me, especially a 4 cylinder, but I never thought someone would animate such ideas. Out of curiosity, have you ridden it yet? If so, how does it handle in the dirt?

[Pezz]

This is the first time I've ever seen this build thread, and I must say, I'm impressed with what you've done to the bike. The thought of turning a road bike to a dirt bike has always amused me, especially a 4 cylinder, but I never thought someone would animate such ideas. Out of curiosity, have you ridden it yet? If so, how does it handle in the dirt?

Unfortunately No, not yet!

It locked up as I was about to set the timing.

I have pulled the rocker cover off and all is fine in the top. I need to go deeper.

The seat height was around 900mm, wheelbase was 1460mm and it had a lot of ground clearance 

[traveler]

when you extended the swingarm....tell me that there are slugs between the pieces of tubing to strengthen the welds!

~Joe

[andy750]

Sorry to hear you couldnt ride the bike after so much work. Could you tell me what barbusters (the metal strip covering the clutch and brake levers) you have on there. Im assuming they will fit any 7/8 bar.

thanks
Andy

[Pezz]

when you extended the swingarm....tell me that there are slugs between the pieces of tubing to strengthen the welds!

~Joe

G'day Joe

They were extended by an engineering shop and are plenty strong enough

[Pezz]

Sorry to hear you couldnt ride the bike after so much work. Could you tell me what barbusters (the metal strip covering the clutch and brake levers) you have on there. Im assuming they will fit any 7/8 bar.

thanks
Andy

Thanks Andy

I was gutted but it will run one day soon.

They are the very early barkbusters, made by Ted Goddard, Superbike racer Peter Goddards father. He has long since sold the business. Barkbusters will fit any Japanese bars. I had to cut the ball off the end of the clutch lever to get everything to fit.

They were on the XL250R donor Bike I purchased for the front end off ebay

[Zaipai]

Well a lot has happened since my last Post

I finished the build, but the night before I departed on the Scrapheap Adventure Ride she locked solid. 

I have pulled the head off and there is oil there and looks fine, I need to go deeper.

It came up really well. Couple of issues were no turning lock once the XR forks were fitted. I bought a another rough tank and inserted some releiving dints but never had to use it. I am still thinking about where to from here. I will get it finished and running. Might build it into a sidecar for the ride next year . . . unsure really

That does bite.. Still the knowledge gained is worth some thing.. Sorry to here it..

.: Scott :.

[Pezz]

Well finally had a quiet afternoon and started to strip the motor to lift it out of the frame.

As I said before looked in the top and all was fine.



I removed the exhaust, engine bars and was taking the alternator off and found some binding marks and some finely ground metal. Reached up and grabbed the rotor annd the motor turned over freely. Beauty!! I donthave to split the cases.





Looks like all I need is another alternator and I will be away.

Upon some checking there was a dowel missing when the alternator was fitted, it cleared and worked fine then moved for some reason binding.

You Live and Learn

[Industrial Rat400f Killer]

Glad to hear it wasn't a more serious problem.

[Alan F.]

Good catch there.