78 gs1000e

[Big T]

Hello, I am new to the GS forum, have had numerous GS bikes, 550E, 850G, 1000E & G
I am looking to redo the top end on a 78 GS1000E
OEM or aftermarket pistons and rings? supplier
Imm over? etc,
Have not pulled it apart yet, rest of the bike is in very good order
Do not want to do a big bore kit ie Wiesco(redid a XS1100 last year)
The compression is at 75psi per hole and after putting oil in the cylinder the compression did not change much so I presume the valves need doing as well, the valve clearance is very tight .0015" on #1 & 4(both IN & EX) less than that on cylinders 2 & 4...way too tight
Mileage? shows 111,200 KM (70,000miles) bike is great shape, paint and seat like new, so I am not sure of the real mileage
Any ideas?
R6

R Six

If that 1000 has been sitting for a while, the rings may be stuck to the pistons. The general consensus around here is to pull the plugs , squirt some high grade pentrating oil or Marvel Mystery Oil into the cylinders and rotate the engine. Repeat 2-3 times over a week.

Get your valves adjusted in the meantime. Check BassCliffs site for the zip tie method if you don't have the shim tool. Get a spreadsheet from Steve

Then, start it up and ride it a few hundred Ks and check the compression again. This often frees the rings and brings compression back up.

While you are essentially correct in thinking an air cooled engine may have worn pistons or bores at that mileage, experience has shown us that lack of valve adjustments tends to burn the valves, because they are no longer closing. This fakes you out because you've put oil in the bores without changing compression. Well, having a valve open gives you the same result.

So, start with what I suggested because it's cheap, like under $50 (because you'll probably need a new valve cover gasket)

If that doesn't work, then you'll have to tear it down and measure. A full oversize piston set, boring, gaskets, valve job and etc will run about $1,500 or so. Many people find that not to be feasable, financially speaking

If you're lucky, some valves are burned and you can do a valve job and refurb for less than a 1/3rd of the above. You'll find the OEM oversize (if you can find them) are waaaay more expensive than the Wiseco kit

[sedelen]

Here's a link to Boulevard Suzuki for parts.

http://www.boulevardsuzuki.com/default.asp

Here's a link to the owners & service manuals.

http://members.dslextreme.com/users/bikecliff/

[Sandy]

A cause of the hanging idle could also be cracked intake manifold o-rings. There's an o-ring between the rubber intake manifolds and the cylinder head, they crack and cause a vaccum leak. There a few members in your area and also just across the border in the US that have lots of experience with these things too.

[rustybronco]

Still woud like to chat

R6

Which is not a problem...But I will tell you now, I'm going to say you are jumping the gun.

unless you determine ahead of time what is causing the low compression on your bike, you 'could' be spending your money needlessly. there is one person on this board who had 375000 km's on His engine without it ever having being torn down.

[azr]

Hey R6. I'm doing the same to my 80 1000, rings, hone, valve lap etc... I bought my std rings and everything else from Boulevard Suzuki out on the east coast. Takes a couple of weeks to get here but they have the best prices and the service is good as long as you talk to them on the phone. Sounds like you have a great project there, throw some pictures up when you get a chance. Nice to see another local.

[R Six]

Great feedback and info
I will try freeing up the rings, with penetrating oil, get the valves adjusted
I will have a look at the intake O rings
The fact that all 4 holes were within 5 lbs of each other is a good thing but 75psi won't get the front tire too high
I bought my first GS850 in 1979 for $2999, I should have bought 2, I put 130,000 km on it and when I traded it for a new 1984 V65 Saber the know it all salesman said "wow great shape for 30,000km....." who was I to argue
Any way off to the shop, stay tuned

thanks to all

great forum

R6........Six is my last name and no Adam 12 was not my dad