• Required reading for all forum users!!!

    Welcome!
    Register to access the full functionality of the GSResources forum. Until you register and activate your account you will not have full forum access, nor will you be able to post or reply to messages.

    A note to new registrants...
    All new forum registrations must be activated via email before you have full access to the forum.

    A Special Note about Email accounts!
    DO NOT SIGN UP USING hotmail, outlook, gmx, sbcglobal, att, bellsouth or email.com. They delete our forum signup emails.

    A note to old forum members...
    I receive numerous requests from people who can no longer log in because their accounts were deleted. As mentioned in the forum FAQ, user accounts are deleted if you haven't logged in for the past 6 months. If you can't log in, then create a new forum account. If you don't get an error message, then check your email account for an activation message. If you get a message stating that the email address is already in use, then your account still exists so follow the instructions in the forum FAQ for resetting your password.

    Have you forgotten your password or have a new email address? Then read the forum FAQ for details on how to reset it.

    Any email requests for "can't log in anymore" problems or "lost my password" problems will be deleted. Read the forum FAQ and follow the instructions there - that's what we have one for...

  • Returning Visitors

    If you are a returning visitor who never received your confirmation email, then odds are your email provider is blockinig emails from our server. The only thing that can be done to get around this is you will have to try creating another forum account using an email address from another domain.

    If you are a returning visitor to the forum and can't log in using your old forum name and password but used to be able to then chances are your account is deleted. Purges of the databases are done regularly. You will have to create a new forum account and you should be all set.

I need some help with my latest GS1000 dilema

  • Thread starter Thread starter terry
  • Start date Start date
T

terry

Guest
I just finished fitting a 1980 GS1000ET engine and 34mm CV carbs to my 1981 GS1000ST, and of course, I don't have a manual that covers the carb settings for the CV's. (my ST has 33mm slide carbs standard)

I've cleaned the carbs, blown out the jets and checked the diaphrams, every thing seems in order, and I wound all the air (mixture?) screws in until they seated, then wound them back out 1.5 turns. This was a bit of a ball park figure based on how they were set when I checked them, am I close?

Anyway, if you can help me out with some techo info I'd appreciate it. No real rush though, I rode it, but it ran like shit, lots of popping and very rough idle, so I did a compression check, results as follows:

#1 cyl 140 psi
#2 cyl 135 psi (so far so good)
#3 cyl 20 psi (crap)
#4 cyl 140 psi.

I tipped oil into #3 and tried the compression check again, it made next to no difference, so I'm guessing that I've got a buggared valve, I did the shims yesterday and the clearances are all fine, all on the looser side of the accepted tolerance (0.08mm) so unless there was some carbon build-up that has now gone and I just need to re-shim it, I'm guessing I've got a burned valve, or a stuffed head gasket. (there appears to be a slight weep at the front of the engine)

Ah well, it fills my days..................
 
If you suspect you have a holed valve you can do a simple leak down test, no equipment necessary.

Put that cylinder at top dead centre so valves are closed.
Take off the exhaust pipe.
Take out the spark plug.
Get some plastic tube (I lied when I said no equipment)
Put the tube to the plug hole so it seals,
- blow into the tube,
- listen for air coming out through the valve.

You only ever burn out exhaust valves from running too lean and hot. A typical hole is about a quarter inch diameter half circle. You've got some compression, so it might be smaller. These motors are too good at helping along an ailing cylinder, until the damage is very evident.

Kim
 
kkmiller said:
If you suspect you have a holed valve you can do a simple leak down test, no equipment necessary.

Put that cylinder at top dead centre so valves are closed.
Take off the exhaust pipe.
Take out the spark plug.
Get some plastic tube (I lied when I said no equipment)
Put the tube to the plug hole so it seals,
- blow into the tube,
- listen for air coming out through the valve.

You only ever burn out exhaust valves from running too lean and hot. A typical hole is about a quarter inch diameter half circle. You've got some compression, so it might be smaller. These motors are too good at helping along an ailing cylinder, until the damage is very evident.

Kim

You were dead right Kim, it was #3 exhaust valve, I've replaced it and lapped the new one in, and the bike is now back together again, starts and runs well, but I suspect the new head gasket isn't sealing, (I've re-torqued it to no avail) as now I'm down to about 70-80 psi in each cylinder.

I'll take it for a ride on Saturday anyway, (only got it back together Tuesday night) but I suspect the head will have to come off again.........
 
terry said:
[ but I suspect the new head gasket isn't sealing, (I've re-torqued it to no avail) as now I'm down to about 70-80 psi in each cylinder.

I'll take it for a ride on Saturday anyway, (only got it back together Tuesday night) but I suspect the head will have to come off again.........

check your valve clearances again before you rip into it, may save some effort
 
Back
Top