84' GSX400 Back to life

[eran_k]

Small update

Small update

Not much to update, I'm waiting for a new tank i got on ebay to arrive, until i fit it i can't do too much in terms of welding and painting the frame.
In the meanwhile i'm cleaning and fixing components like the calliper, MC and so.
Also built a little engine stand so i can work on the engine, i emptied the oil and took off the side covers, where a nasty surprise waited under the generator cover. two of the magnets are shattered and the whole place is filled with oily magnetic debris, the coils don't look to good either. it's a good thing i got a second bike for parts i just hope they will be decent.
I need to figure out how to take the rotor out without an impact wrench.
and now some pics to follow all the long and boring story

 

[Guest]

If your into experimenting like me, Try getting that rotor cleaned up. Get all the magnets and epoxy out. Maybe on a lathe...

Then replace them with individual neodymium magnets

 

[eran_k]

Today i got an important part that will enable me to move on with the build.

It will need some fitting, fabricating a mount for the back which is a single bolt and shortening the (hopefully not re locating) front tank mounts.

 

[Guest]

Good score on the E/S tank!

 

[eran_k]

well since i only get few hours a week to work on the bike, my progress is slow.

I bought a very useful tool today

Got the rotor off after lot of effort, i think i jammed a piece of metal in the crank shaft and will need to extract it

Also took the clutch basket out in order to change the shift shaft
i will replace the springs, do i need to replace the friction plates?

The paint on the covers was a nightmare to chemically strip, it's the factory PC i guess. so i ended wire brushing it off. i will either polish or repaint the covers, haven't decided yet.

 

[Guest]

Inspect the plates for any burnt marks. Measure them and check for flatness. No point in replacing them if they are still in spec.

If you get a gs500 clutch, take the oil pump gears because the gs500 has higher flow gears.
In your pic I can tell they are the lower geared ones.

Check for play in the output shaft bearing just before the sprocket.while your this far.

While your in there, try turning the shift drum by hand and find neutral. Then shim the neutral locator spring. It will help allot when trying to find neutral while riding. If you look under the 17mm bolt on top of the caee you'll see the spring I mean.

To properly strip the paint you need to use aircraft stripper. Not sure where you can get it there but most avation places sell it. I think its peroxide based. Burns skin in 5 seconds :-◇

 

[eran_k]

Inspect the plates for any burnt marks. Measure them and check for flatness. No point in replacing them if they are still in spec.

If you get a gs500 clutch, take the oil pump gears because the gs500 has higher flow gears.
In your pic I can tell they are the lower geared ones.

Wow that's allot of very good info,Thanks!
I'm considering getting a GS 500 motor for scavenging parts, what other goodies i can use from it that are better? (not just in better condition)

Check for play in the output shaft bearing just before the sprocket.while your this far.

While your in there, try turning the shift drum by hand and find neutral. Then shim the neutral locator spring. It will help allot when trying to find neutral while riding. If you look under the 17mm bolt on top of the caee you'll see the spring I mean.

How will i know i'm in neutral? and wht do i use to shim that spring?

To properly strip the paint you need to use aircraft stripper. Not sure where you can get it there but most avation places sell it. I think its peroxide based. Burns skin in 5 seconds :-◇

The one i use also burns the skin, id does take paint off but it takes several thick coats and the paint was still clinging in some areas, what i did was first to use the stripper and then it was very easy to finish of with the wire brush

 

[Guest]

=eran_k;1828791]Wow that's allot of very good info,Thanks!
I'm considering getting a GS 500 motor for scavenging parts, what other goodies i can use from it that are better? (not just in better condition)

Lets see,,, get the clutch itself and use the middle part with the springs and install the oil gear on your basket.
Get the two clutch pushrod and the disengage mechanism in the sprocket cover.
Yours has a bushing type and the gs500 has bearings. The pushrod is a two piece and it stops the shaft from wearing the seal out.
All the transmission is the same except the sprocket. The 500 has a circlip to hold the sprocket on and the chain is a 520. Yours is a 530 chain and held on with a nut.

The shift drum in the 500 is backwards. You can't use it unless you want your shift pattern to be reversed. Although that would work if you want to set your controls way back and put the shifter facing backwards.


The base gasket for the 500 is steel and is half the thickness of the gs400. Its good for a bit of compression ratio increase. Your cam timing would move a little bit but not enough to notice.
GET an older 450 rotor that has 3 magnets. They break less than those with 6 magnets. ( there is actually 12 magnets but the gs450 has 4 grouped together and the 500 has 2 grouped together)

Get the gs500 entire ignition system and carbs.

All I can think of right now.

How will i know I'm in neutral? and what do i use to shim that spring?

Turn the shift drum by shifting or just turn it with a screwdriver. Your going to have to turn the sprocket while you shift. Just turn it until you find first and then find neutral. You'll know it when you find it.

When you take the cap off the neutral plunger on top of the case you will see the spring and pin drop down when you move in and out of neutral.

Shim the spring with anything you want. I actually drilled through one and taped it for an alen screw so I could adjust it without having to shim it. Use washers if you want.

The one i use also burns the skin, id does take paint off but it takes several thick coats and the paint was still clinging in some areas, what i did was first to use the stripper and then it was very easy to finish of with the wire brush

[/QUOTE]


SOS pads take gunk and gasket material off of cases well. Scotch bright pads are easier on the material, they take more scrubbing but do clean well.

Oil will stop stripper from working. I did an experiment with mine. Coated half with oil and wiped it off and then stripped it. The half with the oil on it only lightly took the paint off but the other was completely bare.

 

[JEEPRUSTY]

well my tank look like this:

and since i'm not going to use the side covers i want a tank that looks "cleaner"
i think a regular GS 400 tank will be fine, should it be easy to fit?

The silver tank is worth more than the bike at present.
You may want to flog the pristine tank and look around for a decent used one.
You will be money ahead.

 

[eran_k]

Today i finally got some work done on the bike.

Mounted the tank - we made new frot & rear mounts

Cut the frame's end and welded a "Hoop"

 

[Guest]

Looking good.

 

[eran_k]

anyone got a good "how to" for switches restoration?

 

[cowboyup3371]

What are you looking to do - repair connectors or fix the wording?

 

[eran_k]

Take them apart, clean inside & outside, clean the contacts, fix what needs fixing, paint.

 

[cowboyup3371]

There are many threads here how to do it which you can find by searching using the titles only option.

Alternatively, check out this section of Basscliff's website - http://members.dslextreme.com/users/storagecliff/images/electrical_odd-n-ends.html

 

[eran_k]

Today's labor

 

[Guest]

Cool... however do you plan on something covering that gap and the lip at the rear of the tank? I keep seeing seats that end behind and below it, so if you slide forward in a hurry... ouch!

 

[eran_k]

When the time comes i'll see, either the seat padding will "Fill" that gap or i'll fabricate a plate and attach it to the seat pan

 

[Guest]

Good stuff, would just hate to see that sort of result...

 

[eran_k]

A month later...

A month later...

A month went by before i managed to get to the shop again.
main thing we did was to fix an ugly dent in the frame

also worked on the upper shock mount (finalizing the shape)

Drilled and welded bolts to the seat base

next time i hope to finish fabrication and take it home for dry assembly before blasting and powder coating.
in the meantime parts continue to arrive at my home from around the globe, still need to decide on things like exhaust, headlight etc