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Re: GK76 piston rings and gaskets

Posted: Mon Mar 09, 2015 6:56 pm
by minkathecat
hi mate looked at your ebay listing these should be ok u can get comp gasket for 20 quid on ebay same as bandit gk76a also base gasket looks same on ebay but u can reuse base gasket i can tell ya if u go that way how to do it
be sure bottom scraper is correct size though not 2mm as for some markets this import was made for this difference in size came about with modern materials that where developed ie cast was a lot thicker in the old days soon as they whent to steel they could be made thinner then they whent high tensile
i have just sourced some compression rings the right size for a set only use the compression rings others well within tolerance on mine.

YOU CAN HELP ME OUT WITH A COUPLE OF THINGS WHAT IS THE DIA OF YOUR CAMSHAFT LOBES ON THE INLET AND ON THE EXHAUST LOBES PLEASE (GOT A MICROMETER OR VERNIA) and i will tel u how worne they are these are notoriusly not all that well case hardened
NEXT IN BETWEEN THE CARBS ON THE INSIDE AFTER THE FUEL DILIVERY PIPES ARE 2 PIPES DO THESE HAVE TUBING ON ON YOURS AND WHERE DO THEY GO TO . i know where the top ones go its just that i have seen carb sets on ebay a bit different to mine. :pray:

Re: GK76 piston rings and gaskets

Posted: Mon Mar 09, 2015 6:57 pm
by minkathecat
hi mate looked at your ebay listing these should be ok u can get comp gasket for 20 quid on ebay same as bandit gk76a also base gasket looks same on ebay but u can reuse base gasket i can tell ya if u go that way how to do it
be sure bottom scraper is correct size though not 2mm as for some markets this import was made for this difference in size came about with modern materials that where developed ie cast was a lot thicker in the old days soon as they whent to steel they could be made thinner then they whent high tensile
i have just sourced some compression rings the right size for a set only use the compression rings others well within tolerance on mine.

YOU CAN HELP ME OUT WITH A COUPLE OF THINGS WHAT IS THE DIA OF YOUR CAMSHAFT LOBES ON THE INLET AND ON THE EXHAUST LOBES PLEASE (GOT A MICROMETER OR VERNIA) and i will tel u how worne they are these are notoriusly not all that well case hardened
NEXT IN BETWEEN THE CARBS ON THE INSIDE AFTER THE FUEL DILIVERY PIPES ARE 2 PIPES DO THESE HAVE TUBING ON ON YOURS AND WHERE DO THEY GO TO . i know where the top ones go its just that i have seen carb sets on ebay a bit different to mine. :pray:

Re: GK76 piston rings and gaskets

Posted: Mon Mar 09, 2015 10:24 pm
by djheard91
The inlet cams are all about 33.2 to 33.3mm and the exhaust 32.8 to 32.9 mm all base circles are about 28mm.

My Carbs are currently in bits and I'm not quite sure which pipes you're on about can you see them on this carb break down?

http://litetek.co/docs/CarbParts_Suzuki ... _GK76A.pdf

Re: GK76 piston rings and gaskets

Posted: Mon Mar 09, 2015 11:07 pm
by Variablevalves suck
Is it maybe 71 the breather pipe.

Re: GK76 piston rings and gaskets

Posted: Thu Mar 12, 2015 11:25 am
by minkathecat
could be 71 0r 82 sits right behind the petrol connections hard to get at thats what i want to know where does it go to seen this with pipe on it, mine came with nothing on it
just checking what variable valve seid regards cam size difference the ones i got came of a 1991 same size as your year of manufacture
and the ones on the original bike which i thought was under by .031 ins size and a bit soft for case hardening came of the year of manufacture 1994
So if zuki changed bhp the could have altered the cam and wow a load of other stuff to cdi box different also so if your cdi box goes make sure you keep to year of manufacture and write down the numbers of the box a guy in holland makes them new programable and provides a button for switching mappings he will ask for this no i bleeding know why now. lol

Re: GK76 piston rings and gaskets

Posted: Tue Apr 14, 2015 12:58 pm
by djheard91
Does anybody know what the piston ring gap should be on standard gk76a pistons?

It seems the over sized rings are discontinued which isn't very useful and I don't know how to check if standard rings are going to do the job.

The rings I currently have are a little bit sharp but as I'm currently on a tight budget I don't want to buy a new set if they wont make any difference.

Re: GK76 piston rings and gaskets

Posted: Thu Apr 16, 2015 4:44 pm
by Maelstrom
You do not fit oversize rings into a standard bore. Whatever size bore you have that is the size of rings you use.
So standard bore you fit standard rings.
De-glaze the bore first and fit your new rings. A brush hone is perfectly acceptable for this task.
And everything that Variable and Mink have said is very sound advice.
cheers

Re: GK76 piston rings and gaskets

Posted: Thu Apr 16, 2015 6:39 pm
by Variablevalves suck
If you go download the 73a or bandit manual it has piston and ring clearances that are the same for all bikes from 1988.
No point measuring the ring gap if the bore is past limits.

Re: GK76 piston rings and gaskets

Posted: Thu Apr 16, 2015 7:24 pm
by djheard91
I'm on a steep learning curve, thanks for the help.

Re: GK76 piston rings and gaskets

Posted: Thu Apr 16, 2015 11:01 pm
by Maelstrom
This kept coming up on another forum so I wrote a bit of a story. Might be of some use.
http://2fiftycc.com/index.php?threads/h ... ings.2939/