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Re: 1973 Z1-NOISE IN MOTOR

Posted: Thu Feb 14, 2019 12:29 pm
Author: Adrian90s
Is this the Monk Bretton, Barnsley bike?
My brother Chris I think

Re: 1973 Z1-NOISE IN MOTOR- THE REBUILD

Posted: Thu Feb 14, 2019 1:24 pm
Author: needaz1100r
PJONO wrote:http://z1ownersclub.co.uk/phpBB3/download/file.php?mode=view&id=10951
Well the crank is back. Fully refurbished- a thing of beauty. Already in bike. Rebuild straightforward to date. Cylinders and pistons on Friday. Get crucified if I do them tomorrow as its Valentine's day.

Replaced all inlet valves and guides in head along with exhaust valve and seals. Be nice to get bike up and running. Do possess a certain amount of trepidation that I press the starter -it starts and the noise remains!!

I have to say the engine is a delight to work on having spent ages working on old Harley's- (I've heard ALL the jokes-so don't bother) Bloody time vampires though these motorcycles I go in the garage honestly believing what I need to do will be an hour max- Three hours later................


Great aren't they, you only need a workshop for these, not the fully set up machine shop you need for them old Harleys, not to mention the special tools for reaming and lapping bearings etc etc....

Re: 1973 Z1-NOISE IN MOTOR

Posted: Tue Feb 19, 2019 7:51 pm
Author: PJONO
All back together and ...........NO NOISE. What a relief

All working surprisingly well. Only done about 20 miles but settling all new old and reconditioned parts in. All other cycle/ chasis work all okay. Had an oil light issue which turned out to be centre of switch making its way out of plastic housing. Running it in on mineral 10/40 but a little concerned that oil light isn't going out until about 1850rpm. Suspect dodgy switch as oil belching out of oil gallery okay. Mandatory drip from generator seal- revisit needed with red hermatite

Carbs set up is now crap. Loads of shut down 'run on' and erratic idling. Could this be rubbish compliance fitting rubbers?
Thoughts and tips welcome.

Will do shim check in 150 miles or so. Time it and see where we are then. I understand this is part and parcel of carb setting up. In meantime any thoughts on getting them to run better until I've run it in most welcome

Bike is currently on a set of later 26 Mikuni Carbs. Have early 28 mm set of Mikunis and keep wondering whether it might be better with those on. Similarly if I'm going to refurb a set perhaps better its the original. Any thoughts.

Re: 1973 Z1-NOISE IN MOTOR

Posted: Tue Feb 19, 2019 8:03 pm
Author: 8 Valve Mark
1st thing really, is change the OPS right away PJONO, spray wd40 around the inlets and airbox stubs to see if there's air getting drawn in. (at tickover) a rise in rpm will indicate air drawing in.set the carbs as per the manual..

Re: 1973 Z1-NOISE IN MOTOR

Posted: Tue Feb 19, 2019 8:53 pm
Author: 000zeds

Re: 1973 Z1-NOISE IN MOTOR

Posted: Wed Feb 20, 2019 10:43 am
Author: Ultim8pc
PJONO wrote:Carbs set up is now crap. Loads of shut down 'run on' and erratic idling. Could this be rubbish compliance fitting rubbers?
Thoughts and tips welcome.
Bike is currently on a set of later 26 Mikuni Carbs. Have early 28 mm set of Mikunis and keep wondering whether it might be better with those on. Similarly if I'm going to refurb a set perhaps better its the original. Any thoughts.


As has been suggested, run on could be an air leak.
As regards carbs, it should run OK with 28 or 26mm. If the carbs haven't been stripped, cleaned, rebuilt and setup then I'd suggest you get this done as aged carbs can cause lots of low speed and tick over issues. Most sets that pass through my hands have some problem or other.

Re: 1973 Z1-NOISE IN MOTOR

Posted: Wed Feb 20, 2019 3:33 pm
Author: PJONO
Hi ,

Thanks for thoughts. Fallen down on acronym'OPS.'

Presumably these are the intake rubbers between cylinder head and carb body?

Re: 1973 Z1-NOISE IN MOTOR

Posted: Wed Feb 20, 2019 4:19 pm
Author: Pigford
PJONO wrote:Hi ,

Thanks for thoughts. Fallen down on acronym'OPS.'

Presumably these are the intake rubbers between cylinder head and carb body?



OIL PRESSURE SWITCH :P

Re: 1973 Z1-NOISE IN MOTOR

Posted: Wed Feb 20, 2019 6:02 pm
Author: PJONO
Ahhh....There you go. OPS = Oil Pressure Switch. OMG!

Had a further look at the switch. Phillipe mentioned a mod that I was aware of suggested by Kawasaki for the very earliest switches. Further inspection revealed this to be one of those without the hole therein. I drilled a hole but problem remained. However, decided to tweak switch in mount whilst motor running and it gives a different reading for each 1/16th of a turn so good news is it looks to be the switch. Only about 42 years old I suspect.
Expensive thing ...not as much as an oil starved motor!
Old Harley Stuff fairs much better. (joke)

Re: 1973 Z1-NOISE IN MOTOR

Posted: Wed Feb 20, 2019 6:59 pm
Author: Ultim8pc
PJONO wrote:Presumably these are the intake rubbers between cylinder head and carb body?

More likely to be at the airbox side as the head side is a much tighter fit.

Re: 1973 Z1-NOISE IN MOTOR

Posted: Wed Feb 20, 2019 8:08 pm
Author: Pigford
Ultim8pc wrote:
PJONO wrote:Presumably these are the intake rubbers between cylinder head and carb body?

More likely to be at the airbox side as the head side is a much tighter fit.


But that won't really effect the erratic running ?

Re: 1973 Z1-NOISE IN MOTOR

Posted: Wed Feb 20, 2019 8:25 pm
Author: PJONO
might just put a smear of well- seal non-setting gasket sealer on carb/engine sides if that's help at all.

Re: 1973 Z1-NOISE IN MOTOR

Posted: Wed Feb 20, 2019 9:42 pm
Author: Ultim8pc
PJONO wrote:But that won't really effect the erratic running ?

It won't help.
Also, you also need to ensure that valve clearances and ignition timing is spot on..

Re: 1973 Z1-NOISE IN MOTOR

Posted: Thu Feb 21, 2019 5:26 am
Author: Philippe
Hi PJONO
don't use the old intake rubbers! Don't smear liquid gasket on them! Buy 4 new intake rubbers! These have a lip where they mount on the cylinderhead thus ensuring an air tight sealing. The old ones are hard and the lip doesn't seal anymore. When using the old ones your engine might suck in extra air and the mixture could become too lean.
After all the money you've spent on that engine don't take a chance on using old intake rubbers!
GrtZ
Philippe

Re: 1973 Z1-NOISE IN MOTOR

Posted: Thu Feb 21, 2019 8:36 am
Author: Simonic