The $350 GS850L

[Dropkicknick]

With only 5k on the bike it is doubtful there is anything wrong with the pistons. I would take the engine apart and measure everything before thinking about going to a machine shop. You may only need to re-hone the bores. A mix of kerosene and ATF makes a great penetrating oil to free up stuck rusted parts.

Yea I'm just getting ahead of my self. I know the pistons are most likely salvageable I was just wanting a lighter set. Less stress at higher rpms but if there is nothing out there then I'm not too worried

[eil]

This is pretty much the heaviest GS ever made, even heavier than the 1000s and later-model 1100s, I believe. It's not the one you want to drop good money on performance mods on because all you'll do is take it from "tame" to "meh". (But at the end of the day, it's your bike, do what you want.)

One thing it is, however, is bulletproof. The shaft drive and 8-valve engine add a bunch of weight but they take a lot of abuse and are a breeze to maintain. Looks like yours was at least stored inside, so it should clean up quite nicely. Get the maintenance all caught up, shine it up a bit, and ride it forever.

[almarconi]

Less stress at higher rpms

High RPM's.. that's funny its a GS 850

[Dropkicknick]

A question before I start breaking things. 1st time removing a motorcycle motor that is shaft driven. I removed 2 sets of 4 bolts and it's still getting hung up. Is there a trick to it?

[Dropkicknick]

Apparently no one here has dropped an engine before. Anyway for anyone reading this I loosed the swing arm bolts but did not completely remove them and them ratchat striped the rear tire upwards which moved the drive shaft back with plenty of room to work with.



I then removed the valve cover and cam chain tensioner and tipped it over on to some old army uniforms and it just slid right out.

And here it is

[Dropkicknick]

Fun fun








Feels like this is the only one stuck so I got that going for me... which is nice

[eil]

Yeesh, I'm guessing it spent some time chilling with mother nature with a few spark plugs missing?

[Dropkicknick]

Yeesh, I'm guessing it spent some time chilling with mother nature with a few spark plugs missing?

aye, that spark plug was about 1 1/2 threads deep and cross threaded when i got it

[Dropkicknick]

Well it only took about a month but I finally got the cylinders off. Plenty of penetrates, lubrication and frustration and she popped off.





And now the real fun begins.

[Dogma]

How am I just now finding this thread? Quite a project, but you have the huge advantage of knowing what you're getting into. You mentioned a while back that you've been bookmarking kits. Experience around here has led to some opinions.

Foist, for the carbs, replace only the o-rings and gaskets. Folks say the rebuild kits contain hardware of lower quality than what's already in the carbs. cycleorings.com has o-ring kits, and is a member here. Disassembly, dip and o-rings is usually all that's required. Nessism has a nice pictorial. I think it's linked in his signature.

Gaskets. Bitter experience has led us to recommend only OEM gaskets, most especially for head, base gasket, and related oval o-rings. The Vesrah kit will leak oil at the base within hours of the rebuild. Don't ask us how we know, 'cuz I'm telling you. It's happened to more than one of us. Z1 enterprises is a good source. They know old bikes and have good prices. If it's on their site, they have it in stock. If it's not on their site, email them and they'll get it. I also hear that OEM brake parts are markedly better quality. Again, Z1 can hook you up with kits. Which you'll want, because you probably need new pistons.

You have the infamous leverless petcock. A rebuild kit will not help it. The little plastic dingus that selects between prime and run shrinks, causing a vacuum leak that starves the engine at highway speed. It feels like running out of gas when you can still see gas in the tank. The first time it happened to me, it was pouring down rain. BTW, to prime the carbs, you will need to crank the engine a bit to give the petcock some vacuum and open it. The difference between prime and run on that thing is that on prime, it should hold the vacuum and stay open long enough to fill the carbs. On run, it only stays open as long as the engine keeps sucking on it.

The only other gotcha is the charging system, which I guess is typical for bikes of the era. If the switches and connections in the charging circuit aren't clean, the regulator gets confused and either boils the battery or melts the stator (~$120). There is a Polaris regulator that will tolerate dirty connections without cooking the stator, but you'll have to search the site for it. I can never remember the model number.

Somebody mentioned that you have an odd bike with the 17" rear. What's odd about it is that this is the only L model that doesn't have a 16" rear. All the other GS bikes have a 17, so it's not really that odd. The only truly freaky thing on the bike is that petcock valve.

I guess I don't need to tell you to have fun with your project.

[Dropkicknick]

Ok so ever since I've gotten the cylinders off I've been searching for pistons. 3 of 4 are toast and I have had terrible luck finding a decent set. So my question is if I bring my 1 good piston to a CNC shop would they be able to cut me a new set from that and if so anyone have an idea of cost? I've never had to get any machining done before so I don't have a clue

[ShadowFocus603]

Looking at your pics I'd just clean the pistons up and throw on new rings then lightly hone the jugs and call it a day.

[Fjbj40]

If the pistons are toast, they don't look like it, just buy new ones from Suzuki.

The cost of getting some built would be $$$$$$.

Pousseux in the parts for sale has probably got some also, I can guarantee you they would be very reasonable in price also, great seller to deal with.

http://www.thegsresources.com/_forum/showthread.php?237163-Big-inventory-of-GS-parts-1979-to-1992-all-size-and-models-(reboot)

[Dropkicknick]

the rings in the 3 toast ones are compressed and cemented in. ive tried and mixture of soaking and heat and i just cant get them to free. ive actually damaged the ring grooves with my pick. my father in law is in the CNC business but we dont really get along so i figured i would see what you guys would say before i asked him. id almost rather cut my picky toe off then ask him for a favor. maybe ill hold off and keep cruising ebay.