Z1000ST restore

[myklexfox]

Hi All

So I posted as a newbie, see "another newbie here" with a brief history of me ST that I have had for 31 years or so. Been off the road & just standing in the garage for the last 20 years.

Have now spent a month starting to strip it down. My original thought was that a bike should look its age but after thinking about it for a bit and considering the state it was in (a bit tatty to say the least) it needed spraying & the whole reason it came off the road in the first place was that it was fairly worn out & a reasonably high mileage - 125,000 miles on the clock so was due a fairly major engine service. So it doesn't make sense to "look its age", no point doing a crap paint job, so we'll see where I end up. Here's a re post of the starting point.

Its initially come apart much better than I was expecting, only broke a few bolts - IC ignitor fixings at the bottom of the battery cage (not surprising, this has never been off to my knowledge) - also managed to snap the r/h lower rear shock stud when undoing the bolt, really didn't use much force - honest! Still working on trying to release a few things, front brake master cylinder cap screws (not surprising, these were a pain in the arse when it was used every day), r/h lower engine mounting bolt (to get the crash bar off - bloody thing stuck fast). Took a little while to get the plugs out, but did eventually, so could put some penetrating in too make sure the pistons not stuck. Also was initially worried about getting the swing arm pivot shafts out, but then remembered the "special tool" that an old engineer friend of mine sorted for me & got these out no problem. And then this weekend after getting the cam cover off no problem & making sure everything has a nice coating of oil, engine turned sweet as a nut - very happy with that

But then something very bad after getting the swinging arm out (and making school boy error of pushing the propeller shaft pin in too far my only excuse is that I haven't done any serious spannering for about 15 years) cleaning the back of the engine up whilst pondering if I'm gonna go for a complete strip down, thinking how I could re-spray the engine properly without splitting the crank (something I really don't want to do if I can help it) as it turned so smoothly etc. etc. - noticed something

nasty crack in the crankcase rear l/h lower mounting area. No idea how this could have happened, I last had the swinging arm out 96 when I fitted a "new" 2nd hand propeller shaft as the original had gone, I don't recall seeing any problem then - and I would have thought I would have noticed, but f**k knows what could have happened since to cause this. Still, I do have a spare engine that I bought for parts many years ago which is still in an old mates garage, I have been in touch & he still has it so again I will see where this goes.

Need to clear more rubbish out of the garage to clear room then I can get the spare engine & see what state that is in.

I am beginning to store up some questions re availability of parts, patent gasket sets, advice on spraying (never done it so now's the time to learn) that I would like to ask but I will post these a bit further on. Any

Comments welcome

cheers M

[moizeau]

For a releasing agent I use a 50/50 mix of AT fluid and acetone, really is excellent.

[Pigford]

Good reporting -

[Philippe]

Hi myklexfox
so you started the restoration of your ST, great news!
If I can give you some advice: take the engine out , split the cranckcase, have it welded at the rear and change the camchain for a new one. Change all the camshaft parts for new ones, get the barrels rebored if they're out of specs, get new pistons and rings if the old ones are worn (125,000 miles is very much), put new valves and valve guides in the head and you'll have a "new" engine.
I know it's a lot of work and money but you'll be sure to have a reliable engine!
ST parts are fairly easy to find exept for the long rear mudguard, the throttle cable guide on the right hand side of the upper yoke, the kickstarter and a few other little parts. "Pit replica" has a seat cover for the ST and an original exhaust comes frequently for sale on the world wide web.
I don't know if I asked before but do you have a Kawasaki workshop manual? If you don't, find one, it's worth every penny!
If you have any specific questions concerning your ST, don't hesitate, just ask.
GrtZ
Philippe

[myklexfox]

thanks for the comments guys.

moizeau - I will give that a go thanks

Philippe, yes I do have the service manual & yes it is invaluable, getting a bit tatty now as I've had the manual since 1988 when I first got the ST I was going to put a new cam chain in as a matter of course, I thought I had changed it at some point, but on checking back over my service record notes (I recorded every job I ever have done in the back of the manual - makes interesting reading) it looks as though it is still the original chain! Would be interested to know your thoughts on stripping down the front & final bevel cases ? Looks as though having the correct special tools is a bit of a must for that, which I do not have unfortunately. Also the gear box, again your thoughts would be appreciated.

Was going to have the head & barrels off anyway so I could check the bores out etc. I always found the engine to be pretty bullet proof, had all the head off at 61,000 miles & always checked the valve clearances every 15,000 miles or so, replaced various parts of the cam chain tensioner & top sprockets as required. Will be interesting to see what all the clearances etc are.

Finding the crack in the bottom of the crank had more or less made my mind up to split the crank to repair. Will also get hold of me spare engine to see what state that is in, if the crankcase is whole then simples, will take the bottom half off of that, though I seem to remember that has a hole in it somewhere. Lets see …..

cheers M

[steve-g]

Nice to see another ST being put back on the road.

[myklexfox]

being going back through me service log, yes I did change the cam chain, April 89 at 39,000 miles, think it might need renewing M

[Philippe]

Hi miklexfox
as far as the front and final bevel gear cases are concerned: if they turn without noise (grinding, squeeking,...) or if the gears aren't damaged don't open them, I never did until now. The gears run in oil (they should normally) and if the final bevel gearcase doesn't leak oil it's OK.
If the gears of the gear box aren't damaged, leave them in place.
There is a chance that the nut of the outcoming axle of the gear box, which secures the transmission to the front bevel gearbox, has broken off...it's common and a weak point of the ST. You can mount the front bevel gear box back without the nut as long as the spring is in place.
As far as taking the upper cranckcase from one engine and the lower from another engine: DON'T do it.
They may seem the same but there's a big chance that the two halves are different and that you'll get oil leaks at the mating surfaces of the engine covers (clutch, ignition,...).
There is allso a possibility that the cut-outs for the roller bearings of the cranckshaft are a bit different. Those are line bored and match exactly when you have the original cranckcase halves .
One other thing: if you changed the camchain sprockets sometime in the past with original ones, change them again! The original ones have some sort of "plastic" between the needle bearing and the crown and remember that plastic deteriorates with time .
They may seem OK but renew them in order to prevent work and money in the near future (taking off the head, new gaskets,...).
So, that's it for now.
Good luck!
GrtZ
Philippe

[myklexfox]

Hi Philippe

Thanks for the advice, very much appreciated, all makes very good sense. Had never really thought about the potential difference between crankcase halves & how the crankcase mouldings are bored out. So I will start researching getting the crank fixed, I always thought that alloy crankcases could not be welded, but I guess this is a specialised type of welding that works at lower temperatures? Also had never considered the deterioration of parts in the cam chain sprockets, again makes very good sense.

I know that I did have a problem with the final bevel case drain plug getting stripped which meant that I had to bodge it with sealant at 110,000 miles. Still, not really a biggey I suppose, will just change the oil via the filler and leave well alone. Final bevel case oil should be changed every 18,000 miles which is actually less than when the propeller shaft sliding joints should be lubricated so not really an issue.

Have released all the front bevel case mounting bolts but the front bevel case is stuck fast at present I assume just via the gasket, will keep worrying at it to get it off, just trying to rock it by hand hoping the seal will finally release. Don't want to use any leverage for obvious reasons I am assuming that I really need to get this off as a unit both to make re-spraying the crank easier & for getting the crack in the crank fixed?

Thanks again &cheers M

[Philippe]

Hi myklexfox
the front bevel gear case is attached with 11 M6 bolts to the cranckcase. Make sure they're all out before attempting to remove the front bevel gear case. Mind the lenght of those bolts and put them at the correct place when putting the front bevel gear case back! Check the workshop manual.
If all the bolts are out, the front bevel gear case should come off! I think, but I'm not sure, that there are two knock pins to keep it at the correct place. Try to remove it with a flat screwdriver and give it gentle taps with a rubber hammer. The gasket should release that way. Only if the front bevel gear case is off, the cranckcase can be splitted.
Just a hint when splitting the cranckcase: there are 3 holes in the lower cranckcase halve, 2 at the front, one at the rear. They have an M8 thread inside. spray some lubricant in them and screw a long M8 bolt in them. By screwing those bolts in, you can easily split the cases.
As far as the welding of aluminium is concerned, I don't do it myself but I know that is has to be degreased very good and thoroughly if you want the weld to be strong enough.
Keep us informed of your progress!
GrtZ
Philippe

[myklexfox]

Hi Philippe

Thanks for the info on splitting the crank with the M8 bolts. Have everything numbered for the bolts, pretty anal about such things, been caught out too many times in the past I will post again once I have progressed

Cheers M

[myklexfox]

Hi Everybody

So, just looking ahead, been looking at what I need to do to split the crankcase while its too cold to do much, and I have a feeling this is probably a stupid question, but what is the score on getting hold of a clutch hub holder & flywheel holder?? Clutch hub holder I have seen advertised for 95 euros, expensive but perhaps do-able, but fly wheel holder 300 euros, f*ck me, any alternatives that anybody is aware off or am I just being stupidly naïve just asking?? Would appreciate any comments

Cheers M

[Philippe]

Hi myklexfox
the rotor bolt can be taken out with a pneumatic wrench, as far as the rotor itself : be carefull!
Don't use pliers to take it off, you might deform the metal disc thus causing the glue of the magnets to crack or even the magnets themselves ...if that should happen, you have a problem! The ST rotors are hard to find and no, they're not the same as the one on a J or Gpz.
Use a big rotor puller to remove the rotor but don't tap on it! Do it gentle, the rotor will come off.
As far as the clutch is concerned; you don't have to loosen the central nut for taking the clutch out. If you split the crankcase, the whole clutch will be free. If you want to take the clutch basket off, again, use a pneumatic wrench, The central nut will come off.
Z-power sold a special tool to hold the clutch basket, I have one of them, and it does perform good.
You only need to remove the clutch basket if you want to replace the needle bearing, if not, leave it on.
Looking forward to read about your progress!
GrtZ
Philippe

[myklexfox]

Hi Philippe

Thanks for that, had never considered a pneumatic wrench but after doing a bit of checking I can see that compressors can be hired or some are relatively cheap to buy (looks like I will need one when it comes to re-spraying so will do some more checking on that).

Sorry to keep asking questions & pardon my ignorance but I'm trying to get this all straight in my head, but would using a pneumatic wrench to remove the rotor bolt also turn the engine somewhat at the same time, in which case I would guess that this needs to be done before removing the camshafts & the cylinder head? Or alternatively as long as the head is removed & the cam chain split & taken off (bearing in mind that I am going to fit a new cam chain) then if the engine turns then that would be no problem?

Lastly does the damper cam need to be removed to split the crankcase? I can see in the manual (page 93) it states to remove the damper cam only if the output shaft is to be disassembled, at this stage I don't think I need to look at taking that to bits if I can help it.

Really appreciate the advice & thanks again in advance

Cheers M

[8 Valve Mark]

you can use a 12v/18v impact gun instead of a pneumatic one.