Restoring to factory glory

[cjanderson_90]

Hey guys and gals,



A little background on me. I went to school for motorcycle and small engine repair. Got my degree in that and then went back to school for marine engine repair. Apparently they are two different programs. Worked in the industry for about 3 years, got sick of the low pay and switched to a technology job. Now I run all of the applications and software for a bank.


1979 Suzuki GS750EN

I copy and pasted this from another forum that I frequent



So this is my winter project that i thought I would share with you. I picked up this beauty in November for a whopping $700. Guy told me he "went through everything and its in top running condition". Well I go the bike home and the carbs started leaking instantly. So i pulled the tank and carbs. Did a full rebuild with new o-rings, cleaned the jets, set the float height ect. Then it came time to check the valve clearances as thats probably the most looked over part of maintenance for any bike. Well every valve was too tight to get even my smallest 0.02 feeler gauge into. So I had to get a smaller shim and run it through ever valve to get a baseline of what I needed. Finally got all the shims needed and put them all in. Ended up twisting a bolt off on the cam holder. Nothing a left handed drill bit and an EZ-out cant fix. New gaskets and shes back together. Adjusted the clutch actuater and and cable so now its how its suppose to feel. Im not quite done with her as i need to get new wheel bearings, tires, brake lines ect. Ill try to keep this updated. In the mean time, here are some pictures:



Just got her back home





Tank and Carbs off. Very dirty





valve cover off





This was almost a bad night





The zip ties help keep the valves open when pulling the shims out





Might as well pull the cams out so its easier to put the new shims in





This is a good tool to speed up installing bolts that cant be torqued too high as would happen with my impact





These are as good as everyone says



All buttoned up. For now

 

[GS1150Pilot]

Nice work, cool bike!

 

[cjanderson_90]

Thank you. Im surprised at how fairly modern the bike looks. Needs new paint but I ask people what year they think it is and its usually early 2000s

 

[chuck hahn]

Easy to do shims without removing cams. Just a little flat tip to pop in the notch to lift them and some hemos to grab them out. I have the bucket depressing tool too. Have done the zip tie method also but the toll makes life easier and faster....least thats my opinion.

 

[GS1150Pilot]

I think the retros like the ZRX, Zephyr and Big One have helped perpetuate that notion.

 

[Nessism]

Agree on adjusting the valves without removing the cams.

Be sure to torque the cylinder head while the nuts are easily accessible.

Please check the newbie mistakes thread linked in my signature. It will help you be aware of some common pitfalls in GS restoration.

Good luck.

 

[eil]

Nice bike and thanks for the detailed write-up and photos!

If the the bike hasn't seen any real maintenance in the last few decades, also put rebuilding the brakes on top of your todo list. Even if they seem to work, old brake fluid does a number on the master cylinders and calipers and you really don't want them to fail. Highly recommend replacing the brake lines with braided stainless steel ones if you're still rocking the factory lines. (Which would be about 34 years past their expiration date.)

Welcome!

 

[GSX1000E]

Also do not forget to clean EVERY electrical connection on it as well as adding at least two more ground wires. (One from starter solenoid/RR plate to battery and one from battery to ground.)

 

[cjanderson_90]

Easy to do shims without removing cams. Just a little flat tip to pop in the notch to lift them and some hemos to grab them out. I have the bucket depressing tool too. Have done the zip tie method also but the toll makes life easier and faster....least thats my opinion.

After I got them all checked for clearances, i thought it would just easier to pull the cams. It was a little faster i think to replace them, plus i got a little more familiar with the bike

Agree on adjusting the valves without removing the cams.

Be sure to torque the cylinder head while the nuts are easily accessible.

Please check the newbie mistakes thread linked in my signature. It will help you be aware of some common pitfalls in GS restoration.

Good luck.

I have torqued all bolts to spec. And i have read the newbie mistakes. And I've avoided them all. This is the 7th bike Ive owned. My first full bottom end/top end rebuild was done when I was 18. Ive built bikes that have won best in show for the Japanese class. Hope I havent forgot everything I've learned!

Nice bike and thanks for the detailed write-up and photos!

If the the bike hasn't seen any real maintenance in the last few decades, also put rebuilding the brakes on top of your todo list. Even if they seem to work, old brake fluid does a number on the master cylinders and calipers and you really don't want them to fail. Highly recommend replacing the brake lines with braided stainless steel ones if you're still rocking the factory lines. (Which would be about 34 years past their expiration date.)

Definately on the list of things for this winter. Along with new springs up front and probably in the rear

Welcome!

Also do not forget to clean EVERY electrical connection on it as well as adding at least two more ground wires. (One from starter solenoid/RR plate to battery and one from battery to ground.)

Electrical issues will be the death of me. But ive been fairly proactive with checking the electrical connections ect.

Thanks for the kind words everyone! Hope to get this old bike back on the road again soon!

 

[growler]

nice work, and a good lookin' bike to boot.

 

[chuck hahn]

Take this into consideration when doing shims..youre running a steel bolt into aluminum and steel is hard and will wear then threads out eventually...little by little from repeated removals and installations. the shim toll was made to avoid this removal of the bolts and not tear things up.

8 bucks or some fat zip tie is the way to go to avoid the heart stopping moment the bolt strips or breaks. Thats my take on it.

 

[cjanderson_90]

I think the next time a valve adjustment comes up, ill buy the tool. That seems much easier.

 

[chuck hahn]

I use a screw driver to hold the tool on the rim of the bucket as I depress it so it doesnt slip off. Its real easy to do once you do the first few. Rotate the slot ( notch ) in the bucket so its facing where you can get in and pop the shim up, depress the bucket and pop the shim up, grab with the hemos and pull the shim out.

 

[cjanderson_90]

Now ive read about the RR swap to help with the charging. How many of you also change the stator to a new one? I mean for around $200 I can get a new stator and RR. That would make me more comfortable but how necessary is it(stator)?

 

[eil]

If the stator tests good (the procedure is in the service manual), then there's no reason to change it. Stators typically only go bad from overheating due to a malfunctioning R/R.

 

[JTGS850GL]

If the stator tests good (the procedure is in the service manual), then there's no reason to change it. Stators typically only go bad from overheating due to a malfunctioning R/R.

Actually not completely true. First off stators can measure correctly when doing a static measurement but due to insulation breakdown can fail as voltage/current rises. Static, no load, measurements are not conclusive unless they fail the test. Passing all tests does not ensure complete reliability.

Second, the stator can fail with a working R/R. On a shunt R/R, much of the energy produced gets dumped back into the stator as heat. Eventually this heat will destroy any stator if gone unchecked. True that a bad R/R can damage a stator but it's possible for the failure mode to occur in the opposite direction or even independent of the R/R.

IMHO, the best solution, for complete piece of mind, would be a new or rewind stator along with a series R/R (SH775) wired directly to the stator with no headlamp loop through the main harness and back. That along with a complete check/cleaning of all wiring connections including grounds and fuses. Adding a couple ground points wont hurt either. Add to that a current account with AAA and you should have great piece of mind.

Seriously though... For me, I'd replace the R/R with the SH775 and check charge voltages. If all checks out then you may have extended the life of your existing stator. Just be aware that it may fail from previous damage anyway but I personally would be willing to accept that. You may not though.

 

[cjanderson_90]

I think to play it safe(and since i got the bike so cheap to begin with) Ill get both the new stator and RR and ground everything out better. Last thing I need is to be stranded somewhere with a 500lb razor scooter

 

[cjanderson_90]

Have any of you guys bought an air/fuel gauge and hooked it up to really do some fine tuning? Id really like this to run as well as possible and i have just enough knowledge to get me into trouble. How many have done it with any luck? Im familiar with jet sizes, but the needle positions always confuse me. Also, should this be done before or after the carbs have been synced(sunk?)? Compression is good and the bike idles well after a warm up but I know the previous owner messed with jet sizes and I need this to be right as I plan on taking this bike on some pretty length road trips this summer. Thanks in advanced!

 

[eil]

There are some who have messed with F/A ratio sensor setups. From my reading, I understood that it worked but there are lots of caveats. The easier (and cheaper) way to get a feel for proper mixture at different throttle positions is to do a series of plug chops. Run the bike at a particular throttle opening at speed, shut off the engine and pull the clutch at the same time and then coast to the side of the road. Pull the plugs and read them.

There was a really great article on carb tuning somewhere out there on the interwebs, but I'm unable to find it right now.

 

[cjanderson_90]

I found a good resource and I'm sure its the same one you mean

http://members.dslextreme.com/users/bikecliff/images/highest_rpm_plug_chop.html

Im really kicking myself for not taking an inventory of all the jets but that just gives me something to do now as I await the riding season.

Another question. I read somewhere that changing the throttle tube to an R1 tube will make a big difference and shorten the pull a lot. Has anyone recently done this? Can I buy just the $9 tube from motion pro? And keep my grip sleeve? Thanks again!