What did I do wrong

[chuck hahn]

Well now we know the caps and head were intermatched. Does the guy who sold you the second head have the caps?? May be worth a shot. What was wrong with thew original head?

[Bob Shaw]

The original head had a broken body around a inside bolt hole. I'll check to see if I can get the caps, doubtful though.

[Grimly]

The head and caps are factory-machined and matched for each other.
Trying to intermix them is futile, as all it will do is (if it were to work at all) wreck things in short order. If the gods smiled upon you, you might get lucky and end up with a suitable match by pure fluke, but that wouldn't be common.

As headsbikesmopars says, it's not insurmountable even using diy tools, but be careful.
I wonder if the genius who discarded the idler sprocket also threw out the cam caps. Who knows where many of these old parts come from - some greedy ebay sellers seperate every item, even bits that should stay together, to maximise profits.

[GregT]

Are you using the alignment dowel pins when installing the cam caps ? I believe the cams are tight because the cam journals (caps) are wrong for the heads or have been dropped , does not take much to push the ID of cam caps a thousandth or two. I have used a wheel cylinder hone to'hone' the ID a half a thousandth or two if that is the issue that method will fix it. Torque the caps in place without the cams and measure the ID in couple places and measure the camshafts journals themselves and you will know. If you do use the wheel cylinder hone , go slow and use some spray oil as you go . Do one journal at a time . Hone a few seconds and retry after, it will take some time but you will get there. When you clearance one move on to next and CLEAN as good as you can . This is best with the head removed . If you have another set of cams you could try them to verify its the camshafts . Keep us
informed as to what you find.
Terry

Yes, it can be done as Terry says. I find that sorting out which cap is the tight one first is best. Engineers blue on the cam journals will tell you which cap and where the tight spots are.
I've had to align hone a couple of FZR1000 heads - owners will keep on mixing the caps up as they are not clearly marked.

[fastbysuzuki]

I would agree with GregT take off the head remove valves clean cams and journals wipe a very thin coating of engineers blue on the camshaft ( where the caps run) then evenly tighten the caps so that you can still turn the camshaft this will deposit the blue onto the journals these are know as high spots and it is these that need scraping/honeing you will have to repeat many times. I was a maintenance engineer all my working life and scraping was how we bedded in white metal bearings using the method described above.
personally I would prepare scraping as it is more controllable which ever method you choose patience is not a virtue it is an absolute necessity
here is a link to the type of scraper we used https://www.ebay.co.uk/i/15349719573...SABEgIavfD_BwE

all this is assuming the alignment is not excessive which would make it futile to attempt doing it.

[Bob Shaw]

Hi guys,
Before I received the newer posts I removed everything and put the cam caps back on the cylinder hdad. I used the brake cylinder home method suggested and now all rotates. I don't know how much torque there should be on the crank. My manual says nothing but to check and make sure all moved freely. It does move freel, even checked it by turning it over with the starter, I also checked the torque and it takes 15 foot pounds to rotate the engine. Is that acceptable should it move more freely?

[Grimly]

Hi guys,
Before I received the newer posts I removed everything and put the cam caps back on the cylinder hdad. I used the brake cylinder home method suggested and now all rotates. I don't know how much torque there should be on the crank. My manual says nothing but to check and make sure all moved freely. It does move freel, even checked it by turning it over with the starter, I also checked the torque and it takes 15 foot pounds to rotate the engine. Is that acceptable should it move more freely?

The only way you can be sufficiently sure, is to mic it up.
Get a cheap set of bore gauges and see what the new internal size of the cam caps are when they're bolted down. Also mic the cam journals. Consult the Book of Lies and see what the clearances should be.
As far as I recall, I think the Haynes manual has camshaft journal clearances listed, but I might be wrong on that specific.

The magic happens when you stop at just the right amount - too tight, obviously disaster looms, but too slack and they'll rattle around and self-destruct eventually, just like a worn-out set. Be sure - as Nessism says, "To Measure is To Know".

[Bob Shaw]

Ok, thanks!!

[bobgroger]

I am using the original cams from the old head as well as the caps. I have not had the head milled. I had the bike running and then I lost a cylinder so I took everything apart again and started over. I did not remove the head. That will be my next step. Thanks for your input... PS: If the cam caps are not in line with the cams how do I rectify that??

Buy another head, with the caps. Cheaper than the required machine work.

[Bob Shaw]

I have looked into another head. I found one that's complete. However, the valve cover has 16 holes whereas mine, on a 1982 gs850g, has 19 holes. I have checked part numbers for the cylinder head gasket, 11141-49410, and all are the same for 1979-83. I also find that 1979 was the only year for the 16 hole valve cover. Does it make any difference if the valve cover and cylinder head have 16 instead of 19 holes as long as the cylinder head gasket are the same. The seller states this cylinder head fits1982 gs850g??? I hope this makes sense. Thanks in advance for any help.

[Grimly]

The '79 cylinder head would necessitate the fitting of the '79 slide-throttle carbs too (plus carb boots). It's one of the changes they made from the first year of the 850 to the subsequent years. Most of the changes are minor, but that one is a bit awkward and involves extra expense.
What the seller says is true, but he's being a touch disingenuous in not mentioning the extra work and expense needed.

[Bob Shaw]

Thank you. I have emailed the seller and have yet received an answer to my questions. You may very well have answered them. Again, many thanks.

[Bob Shaw]

Grimly,
The last time I contacted you, you spoke of a 79 cylinder head. Would that include an 82 gs850gl cylinder head as well concerning the carbs. I'm searching eBay and all I find are models with 16 bolt valve covers. As I stated before, I have a cylinder head with19 bolts.
Thanks for your assistance in advance.

[Steve]

The 850 heads came in three basic "flavors":
1. 1979 had 16 cover bolts and smaller inlet ports for the VM carbs
2. 1980, 1981 and some of the early 1982 had 16 cover bolts and larger ports for the BS32 carbs.
3. Mid-year 1982 and on had 19 cover bolts and kept the larger ports for the BS32 carbs.

1982 was unique with the silver head, 1983 and newer were all painted black. Yes, I said "and newer".
We did not get any past 1983 in the US, but others around the world got them through 1988.

.

[Bob Shaw]

So, in answer to my question, can I use a 1982 cylinder head with 16 bolts and a matching 16 bolt cover from a GL on my G. When I read the I info from the sellers, the head is supposed to fit on the jug. I'm concerned with the switching to a 16 bolt valve cover. Thanks.