• 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.

Putting it back together....1981 GS750

  • Thread starter Thread starter Anonymous
  • Start date Start date
A

Anonymous

Guest
I bought an '80 GS 750 a few years ago, and *gasp* it had charging problms....unfortunalty I didn't have the vast resources of this site...namely YOU.

anyway, I parked it for a while, and decided to work on it this summer. It also had an oil leak in the head gasket, so I pulled everything off down to the heads, and cleaned it all up. I managed to get all the carbon of the piston heads, and the valves. I ordered the gasket today, hopefully it will be here soon.


Anyway, novel over, have to put this all back together, and was wondering what things would be important to inspect/note/adjust as I put it all back together.

I don't have a manual, so I would also like it if anyone could post the timing settings, and valve clearance stuff. This is a TSCC engine btw, with what appears to be valves that don't need shims. I am nervous about getting the cams back on, and the bike timed, as I don't want to mess it up and break stuff.

any help/pointers/tips to this novice bike machanic would be appreciated.



Also, will the stator/Reg.rect from a 77 750 work on my 1980?
 
The best advice that anyone could give you is to buy a manual. They are invaluable. You will be able to find the answer to this question and all the others that will arise. A good deal for less than $20. But, if you don't want to buy one, then go to your local library and check one out.

I'd tell you what you want to know, but I don't have a manual for your bike. Just for grins, put your hometown on your profile. Maybe another member lives close to you and would be willing to help you.

Terry
 
well, after lurking, (and waiting for gaskets, darn the budget thing anyway) I have decided several things. Oh, and by the way, my bike was built in 1980, but is an 1981 model

1. The little hole I covered on my #2 carb was there for a reason, looks like the guy who had the bike before me had some issues
2. there is a lot to get this back on the road.

List of what I think I'm going to do..

1. Clean the carbs (did it a bit last year, but not taking it ALL the way apart and soaking it) and replace any bad rubber parts
2. Clean the petcock (and replace, cause I think the vacuum thing is bad, as it was DISCONNECTED when I go the bike, gonna strip it down and see tonight.)
3. Reshim the Valves and check to see how they are seating (will gas in the top of the head work to see if it's leaking?)
oh, and my valvse dont' seem to have "shims", they seem to have a little bolt you can turn to adjust the way the valve go up/down a small amount...is this normal?
4. Oil my chain (old shafty here, that's all I've really ridden up till now....too bad I didn't think about it before buying it, my knees already hate me)


anything else I should do with the head off the bike, and trying to get it back into good running condition?
 
nweaver said:
3. Reshim the Valves and check to see how they are seating (will gas in the top of the head work to see if it's leaking?)
Click to expand...

yes but be careful! :lol:
oh, and my valvse dont' seem to have "shims", they seem to have a little bolt you can turn to adjust the way the valve go up/down a small amount...is this normal?
Click to expand...

Yes, no shims, be careful to not strip the adjuster with the locknut though

anything else I should do with the head off the bike, and trying to get it back into good running condition?
Click to expand...


The valve stem seals aren't a bad idea
 
Update from night number 1...

printed Carb cleaning guide, started cleaning carbs (number one finished, not goint to start 2 till one is assembled again), picking up dip in the morning (live out of town a ways). stripped Petcock down, darn guy had the vaccume disconnected, and the petcock on "prime" with another shutoff switch just below that main one.....

How can I test the petcock valve? I stuck a tube on the fuel outlet, and sucked, but got air no matter what position the petcock was in. Shouldn't It stop if it's "On" or "Reserve" cause I don't have a vacuum?

I was unable to get the "Air Screw" out of the number one carb, I sprayed cab cleaner in there, and gave it a few minutes, but it just stripped a bit. How crucial is it to get that air screw out? I would prefer not to have to tap it out, if it will be ok. Will dipping the body while it is in hurt the O ring in that?


Thanks for the Help

Nick Weaver
 
try heating up around the screw with a heat gun or hair dryer then soaking down the screw in liquid wrench, let set awhile before trying again,the 0-ring will not take kindly to the dip
 
I am having a hard time putting my petcock valve back together, and can't seem to find my manuals (I have one for 550, and one for 850-1100, but not for the 750) :roll:
I was armed with my digital camera, but was to anxious to get pictures before ripping into it, and I'm not sure if it was assembled correctly in the first place. I am looking for an exploded view of one. Is the petcock mostly the same setup for all the GS's around then?
 
Hope this helps....
site1119.jpg
 
Dave, I think the drawing you posted is for a 1980 petcock. It is different from other years. At least all that I have seen, which is not that many though. I'm glad you posted it, because I did not know the correct position for prime and ON and was going to ask for help.

Terry
 
TheNose said:
Dave, I think the drawing you posted is for a 1980 petcock. It is different from other years. At least all that I have seen, which is not that many though. I'm glad you posted it, because I did not know the correct position for prime and ON and was going to ask for help.

Terry
Click to expand...


actually the 81s had that one too,my 82 is different(guts are the same though) but it's in the 82-83 factory manual?
 
hoping I can get that screw out...the head is stripped some, and the screwdriver wasn't wanting to bite much...would an impact driver work still? If I can't pull this out, should I tap it and replace the screw?

I really don't wanna be tapping the thing out, if I sprayed the inside of the carb and cleaned it really good, and left that one alone, would it really hurt the bike much? Is that a screw I need to adjust?
 
nweaver said:
hoping I can get that screw out...the head is stripped some, and the screwdriver wasn't wanting to bite much...would an impact driver work still? If I can't pull this out, should I tap it and replace the screw?

I really don't wanna be tapping the thing out, if I sprayed the inside of the carb and cleaned it really good, and left that one alone, would it really hurt the bike much? Is that a screw I need to adjust?
Click to expand...


Heat it up and let soak in liquid wrench,for a hours, then heat it again and try, you need to be able to adjust it
 
anyone got valve clearence for this year? book is on it's way, but I can't wait :)
 
nweaver said:
anyone got valve clearence for this year? book is on it's way, but I can't wait :)
Click to expand...

Intake 0.025-0.052 mm
0.0010-0.0020 in

Exhaust 0.040-0.067 mm
0.0016-0.0026 in

For a TSCC Engine GS750

Terry
 
Thanks....I got the petcock back together, not sure if the vaccum will work, but it doesn't let me suck air through it on res or run, so I think that is a good sign.

2 carbs cleaned, 2 stripped and uncleaned air screws...I am debating about getting new air screws, or just letting it go...I know that could be bad, but I am trying to get the bike running again, and at minimal cost. I have tried the liquid wrench/heat stuff, but no luck. Can I buy just the airscrews from somewhere?

One more question, I cleaned up the underside of the head really good with a soft wire brush/dremel. I couldn't compress my valves to get the seat at all. I poured some gas into the top, but it's hard to get it on just the valves. It seemed to have a little bit of leakage, should I pull out the valves and use grinding compound on the seats/valves to get a good fit? are valves inexpensive for these bikes? 16 valves can get spendy real quick. I want to do this right, but I don't wanna spend hundreds doing stuff like valves unless I have to to make it run fairly well. It was running ok before, but the carbs needed cleaned/sync a bit, and the head gasket was leaking oil.
 
Quick bump and a question, does anyone know if you can buy new airscrews somewhere?
 
daveo said:
TheNose said:
Dave, I think the drawing you posted is for a 1980 petcock. It is different from other years. At least all that I have seen, which is not that many though. I'm glad you posted it, because I did not know the correct position for prime and ON and was going to ask for help.

Terry
Click to expand...


actually the 81s had that one too,my 82 is different(guts are the same though) but it's in the 82-83 factory manual?
Click to expand...

Dave, the '80 models were the only ones to have that kind of petcock. They changed to the petcocks with a lever on the '81 bikes. Both my '81 750 and my '81 1100 had the lever style of petcock.

Hap
 
You must log in or register to reply here.
Back
Top