Splitting the cases

[wera racer]

Okay, I'm about to take the plunge and split the cases on my 78 GS1000 vintage racer. I want to go through everything real well. Any caveats, suggestions, or words of advice before I make the plunge? Any special problem areas I should check, things I should replace while I'm in there, etc.? Many thanks! Rick

 

[Nessism]

Few things...

Inside the clutch cavity area there are several phillips head screws that need to be removed. Use an impact driver on these, and consider hitting them with a little heat too in order to get them loose. These parts are loctited in place and you will struggle to get them lose with a regular screwdriver. For loctite I use Three Bond. They have a medium strength variety that is rated for high heat - green in color. Good stuff.

When you go to torque the cases back together use an in-lb torque wrench and torque to the lower end of the spec range since the bolts can strip out pretty easily.

Many people install the RH crank seal backwards. The factory parts fishe diagram is confusing in this regard. Orient the seal with the raised areas facing toward the bearing.

OE gaskets are best. Athena base gaskets are junk, and several people have reported problems with Veshra (sp) rubber O-rings, such as the ones around the oil feed ports in the base gasket.

Do not use any sealer on the gaskets. For the crankcase halfs, 1194 Threebond is the stuff.

When honing the cylinder use a 240 - 320 grit aluminum oxide bottle brush hone. Don't use a straight hone for used cylinders, bottle brush is better.

Good luck and have fun.

 

[wera racer]

Many thanks, Ed!

 

[gs1150streetracer]

Yes its not as hard as you think,take Eds advice,Not sure if you are taking the crank out but there is a small pin on the pick up side of the crank lodged inside the crank bearing and the engine case,Also once you get the shift forks inplace make sure the bike goes threw all the gears before you bolt it up complete.I took mine apart and put it back together 3 times now,Ray walked me threw it on the phone now the first time. I almost feel like an Engine Bulder..hahah ..Its not that bad give it a Go..

 

[posplayr]

Many thanks, Ed!

Take some pics, I need to split my 750 cases to stop an oil leak.

 

[waterman]

Just a couple tips. Thoroughly clean exterior of motor before working, most likely a given.

Secondly, if the 1000 is similar to 650, there are two allen head bolts on the inside of the oil pan, near the oil filter, which are accessed from bottom. To get these out you need a stout T wrench or long allen socket. Mine broke free with a loud crack, thought I had snapped them off. Royal PITA.

Finally, as I removed bolts, I measured them and placed them in a holey piece of cardboard to keep track of there location. Made replacement a lot easier.

If this is first crankcase split, pay attention to little parts that fall out when separating halves. I spent the better part of morning searching for own of the little blocks that goes under rear chain guard. Likewise, pay attention to the pinned bearings, they only go together one way.

 

[sharpy]

Weld 2 gear and get it done by someone smart. New cam chain. Make it all clean then clean it again. Yes i only use genuine Suzi parts. Saves the hassle. Good time to paint it IF you want too. Only top half of the case is painted as standard if ure doing silver other wise just do the whole thing in black or whatever. Taking out all the barrel studs lets it fit into ure oven for a good bake. Heavy duty studs? Depends on how tough its going to be.


Painted and baked

 

[Guest]

 

[rapidray]

I can't believe no one has told you this yet! You CAN'T get the parts TOO clean before you reassemble the engine!!! Ray.

 

[wera racer]

Thanks for all the advice, guys. Much appreciated.

 

[BlackStar]

 

[Nessism]

Take note of this O-ring and don't forget it. This passage is for the oil feed.

 

[sharpy]

I can't believe no one has told you this yet! You CAN'T get the parts TOO clean before you reassemble the engine!!! Ray.

Hey Ray, you going blind in your old age?....

"Weld 2 gear and get it done by someone smart. New cam chain. Make it all clean then clean it again. Yes i only use genuine Suzi parts."

 

[Nessism]

Hey, did anyone mention cleaning the parts really well?

Another tip is to remove/clean the crankcase dowels and the mating holes they fit into. Corrosion and sealer tend to foul the dowels which keep the cases halves from sliding together easily.

 

[sharpy]

Hey, did anyone mention cleaning the parts really well?

Another tip is to remove/clean the crankcase dowels and the mating holes they fit into. Corrosion and sealer tend to foul the dowels which keep the cases halves from sliding together easily.

To save damage when removing those dowels use a rat tail file and treat it like a easyout and twist out that way. Save marking the outside if all goes well.

 

[wera racer]

Thanks for the tips and pics, guys. Much appreciated. Anyone got a picture of what a welded second gear looks like?

 

[sharpy]

Its nothing special. Just a gear thats been welded a little on one side. As in 12-2 oclock and 6-8 oclock poisition. NOT fully all the way around like mine got done by a speciality performance shop. Gear went blue and soft. Was not impressed. Oh and make sure everything is spotless.

 

[wera racer]

I'm reassembing the cases and I've been fighting the shifter pawl all day and can't get it to work properly. If I just lightly snug up the the two pieces of sheet metal that are held by the four phillips screws, it seems to work okay and will shift through the gears. But once I tighten them even a little, it won't shift.

When I disassmbled the cases I accidentally let the pawl ratchet mechanism come out, releasing the two springs and ratchet wedges. Is it possible I've got them in the wrong places? The manual says something about one being narrower than the other and that one should go towards the shifter. The both look the same, but that's what I'm going to try next. I don't know what else it could possibly be.

Thanks, guys!
Rick

 

[wera racer]

That fixed it. I had those little buggers in the wrong place. Shifts fine now.

On to the cylinders, pistons and head. Before teardown the motor burned some oil until it got good and hot. I replaced the valve seals twice, which did nothing, so I'm guessing it needs valve guides, at the least.

I'm a decent amateur mechanic, but no machinest. In your opinion is it better to take the cylinder and head to a professional to sort out and determine what needs to be done (pistons, rings, valve guides, etc.), or should I tackle this myself?

Since it's a roadracing bike, there will be future (and perhaps frequent) teardowns, so the more I can learn to do myself, the better off I'll be.

However, since I pay retail and the pro wholesale, what I save on labor may just go towards the parts. I just don't have the tools (at least not yet) and expertise to accurately mic pistons to cylinders and know what to look for and what to look out for.

Any advice?
Rick

 

[Guest]

Where are you at? Maybe someone on the board knows a good engine guy in your area?