Top end rebuild

[Suzuki mad]

Each of the valves sits in pockets which are filled with oil. (Thats another trick for when you rebuild the head!) Its possible that some PO has drilled and tapped too far into the casing causing it to leak. From the sounds of it this head had been in the wars.

Suzuki mad

[doctorgonzo]

Each of the valves sits in pockets which are filled with oil. (Thats another trick for when you rebuild the head!) Its possible that some PO has drilled and tapped too far into the casing causing it to leak. From the sounds of it this head had been in the wars.

Suzuki mad

You got it! That explains it. Yes, PO drilled too deep and when I ran a tap (didn't drill AT ALL only ran a tap down it) down the already heli-coiled hole I managed to hit that black gold... texas tea.... took the tap out and oil followed. I'm going to try teflon tape on the bolt and see if I can stop minimize that leak so it remains rideable while doing this head.

[doctorgonzo]

OH yeah.. odds this thread has about 1000 bumps coming over the next month or so.

Camchain:
With only 30K miles on my chain, odds are it's still within spec, I looked at the aftermarket ones on Z1 ($30) and the OEM ones ($70). My question is this. Would you install the my old OEM one I have on the new head if still within spec? How would I even do that? Pop a rivet and put one back in... use a "master link? I assume the aftermarket aren't as good. If I should go with a new one, use OEM?

[srsupertrap]

Ok, looks like I have located a head. He is supposed to call back shortly for a price for the whole shebang from the head up (cams, cam ends, cover, etc...). I don't have my shop manual with me which would probably shed some light on this, but... My philosophy is, while I have a head, off the bike, I should rebuild it (even if it may or may not need it) before I put it on. I have never been down that far in a bike engine (car once or twice) so looking for some insight. If you were doing it "right", not "no expense spared", but willing to spend some money, what would you do? Valve seats... new valves... measure the valves and only replace if too worn... take valves out and get the carbon off... new cam chain.... I want to put my parts list together as soon as I can so they and the head ship at roughly the same time.

Have your Machinist inspect every threaded insert in the head, paying close attention to the Cam Bearing Caps and valve cover bolt holes. These are all merely machined into the aluminum head and are prone to fail (pull out).

[doctorgonzo]

Have your Machinist inspect every threaded insert in the head, paying close attention to the Cam Bearing Caps and valve cover bolt holes. These are all merely machined into the aluminum head and are prone to fail (pull out).

Good one. Every bolt hole will be inspected, you can bet on that. I was going to have the ports maybe lightly worked to just smooth them out from the rough casting, (unless they want too much money in which case I will try and do it myself), so could have them checked then.

[srsupertrap]

Good one. Every bolt hole will be inspected, you can bet on that. I was going to have the ports maybe lightly worked to just smooth them out from the rough casting, (unless they want too much money in which case I will try and do it myself), so could have them checked then.

Don't ask why I know . . .

[doctorgonzo]

Don't ask why I know . . .

Well....
This whole adventure started because when putting my new 4 into 1 on I discovered the head on my bike had a sheared bolt, 4 holes already heli-coiled, and a hole that was just drilled out. In trying to fix that mess I broke a tap off in one, and an extractor in another, and the drilled out one, after installing heli-coil and tapping now leaks oil at an alarming rate when the bike is running. What a mess, and you can bet the new head I am paying dearly for will be better than the day it rolled off the line before it goes on.

[terry]

Well it's a lesson we've (we who have pulled these bikes apart over the last 30 years, that is) learned the hard way, that exhaust bolts break real easy.

I'm currently building one bike out of two, I bought a "bargain" 1980 GS1000E with some Yoshimura gear, (turned out to be a rusted out Yosh pipe that literally fell apart when I grabbed it by hand and a big bore kit) it's been sitting under a tarp for 5 years, I dropped the old oil and filter and cleaned the carbs and it started and ran on all four right away, so I know the engine is good, at least.

The frame and forks (and most other cosmetic parts) were another story, but I've got a good 1980 GS1000E frame here and some GS1000G forks, and thanks to Tom MLC I've got some really nice blinkers and an ignition switch. Anyway, I digress.

I needed to remove the remains of the (paper thin) Yosh pipe, so as the engine would run, I fired it up and when it was hot I switched it off and then sprayed a home made penetrant (a mixture of diesel fuel and stale gasoline, with a dash of acetone) liberally on the rusty bolts, (this bike has spent it's life in Melbourne's bayside suburb of Frankston so every part of the bike was salt water effected, to some degree) let it cool down, then repeated the process all day, then next morning I started the bike, let it warm up, switched it off, then (with insulated gloves on) I unscrewed every bolt, with no breakage!

My advice to anyone, is get the bolts hot and they will (almost always) come out. Oh, and no-one answered your question about cam chains, my advice again is to ditch your OEM chain and buy one of Z1 Enterprises Tsubaki flat link race chains, they're probably twice as strong as OEM. I know our bikes aren't chain busters like my other passion, old Honda CB750's, but even so, you'll never bust a Tsubaki. Cheers, Terry.

[doctorgonzo]

Thanks Terry, for the input. I'll go for the Z1 chain I think. I had noticed when I bought the bike that two exhaust bolts were missing, but the nightmare landscape I found was way beyond what I expected.

[gearhead13]

I just have to ask why Suzuki didnt put studs in for the exhaust? strange?. I think when I get my new pipe I really really hope i dont have any big problems with the bolts. Maybe I will look into putting studs in when the new header goes on. Just have to find high grade studs the right size.

[terry]

I just have to ask why Suzuki didnt put studs in for the exhaust? strange?. I think when I get my new pipe I really really hope i dont have any big problems with the bolts. Maybe I will look into putting studs in when the new header goes on. Just have to find high grade studs the right size.

Buy some 1975-1978 Honda CB750 studs mate, they go straight in. I'm still using the bolts, but I use stainless steel cap heads with anti-size compound (copper grease) on the threads and I've not broken one in years. Cheers, Terry.

[Suzuki mad]

Modern Hon**'s use the stud method for the exhausts so if the nut don't come off the stud comes out of the head all OK.

Did this mod with my first GS1000E in 1982 after stripping the thread putting the exhausts back on. Used a Morris Marina exhaust stud, a brass nut and a washer. Never had a problem again.

Most cars use the same system and the thread is correct for a GS. If you can find the copper flanged nuts that go with them thats great.

As for the cam chain, I'd leave the original in there if its within spec.

Suzuki mad.

[terry]

Modern Hon**'s use the stud method for the exhausts so if the nut don't come off the stud comes out of the head all OK.

Did this mod with my first GS1000E in 1982 after stripping the thread putting the exhausts back on. Used a Morris Marina exhaust stud, a brass nut and a washer. Never had a problem again.

Most cars use the same system and the thread is correct for a GS. If you can find the copper flanged nuts that go with them thats great.

As for the cam chain, I'd leave the original in there if its within spec.

Suzuki mad.

Geezus, Morris Marina? I haven't heard anyone utter that curse for 30 years, ha ha! BTW, how can you measure a cam chain chain (to determine if it's still "within spec") if you don't remove it from the engine mate? Cheers, Terry.

[Suzuki mad]

Suzuki workshop manual states:-

Cam Chain 20-pitch Length 157.80 (6.213)

Cam chain size DID219FTS

No of Links 120

Suzuki mad

[gearhead13]

I had a yamaha xs400 that I put a mac pipe on and it had studs, I dont remember exactly what happened, but I ended up having to drill and tap one of the holes larger and getting a bigger stud for it. Chev auto stud I think.