1978 GS 750 Indiana Barn Bike rescue

[Ledyard]

Well, we will see how solid my plan is after finding out if the machinist can even get the stripped screw out of the side panel. If not, my little educational project might become an adventure in parting out.

[azr]

I hate to be bearer of bad news but you put your carbs back together wrong. The #2 and #3 carbs bodies are wrong. You can tell which ones go where by first looking at the float bowl screws, they will always point to the outside of the bike, like on your #1 and #4 bowls BUT then you have to look at the sides of the carb bodies in the hole for the fuel T's. On the #1 and #4 bodies the hole will not go all the way through as it does on #2 and #3. Bit of a pain to pull them apart again but trust me it's wayyyyy better to catch it now then after you've put the bike all back together and can't figure out why it won't start, as me how I know that . Projects looking real good so far.

[Ledyard]

Good catch, and thanks!

[chuck hahn]

Rob...since the pic I saw was of the back, the order of the carbs is inconclusive. May be that just the bowls are in the wrong spots.

Best way to tell if 2 and 3 are transposed is that 2 has a VENT hole to the RIGHT side of the thoat and 3 does not.

3 has the vacuum nipple for the petcock to the LEFT of the throat.

1 and 4 are self explanatory because the outer hole which would normally be for the transfer tubes is blocked off. 1 is blocked off on the left side of the body and 4 is blocked off to the right. Also 4 has the vent tube to the left side and 1 doesnt have any nipples at all.

[azr]

Rob...since the pic I saw was of the back, the order of the carbs is inconclusive. May be that just the bowls are in the wrong spots.

Best way to tell if 2 and 3 are transposed is that 2 has a VENT hole to the RIGHT side of the thoat and 3 does not.

3 has the vacuum nipple for the petcock to the LEFT of the throat.

1 and 4 are self explanatory because the outer hole which would normally be for the transfer tubes is blocked off. 1 is blocked off on the left side of the body and 4 is blocked off to the right. Also 4 has the vent tube to the left side and 1 doesnt have any nipples at all.

What he said...

[Ledyard]

Thanks -you guys are awesome. I'll do some checking this weekend to make sure they are reassembled correctly. Very helpful information.

Before I do much of anything else on the project, I have to figure out how to get the engine out without removing the left hand crancase cover (where the clutch cable runs through). That is where I've got a totally stripped screw. If I can get the engine out, I'll take it to a local machine shop to see if that screw, and two snapped off exhaust bolts, can be removed. Have to say, I'm feeling pessimistic at the moment, but will keep calm and wrench on.

[chuck hahn]

You have to unlook the clutch cable...inside the secondary little cover on the sprocket cover. Unscrew the cable from the sprocket cover and remove that from the area.

Next, remove the shift lever and the sprocket cover and you can then remove the engine in one piece. Everything comes out the right side of the bike. As youll see, the left engine mounts are welded to the frame and the right ones are bolted on.


IMPORTANT EDIT... Just reread and I see the sprocket cover is the one with the stripped screw head. OK..do this. get a 3/16 drill bit and carefully drill off the bolt head. Go in a little at a time and get real close to the cover surface without actually hitting it.

Next reach in with a small flat tip and get along side the head and pry the head off using the cover side for leverage..may need to go from side to side and "work it " but the head will eventually snap off. Now you can remove the cover off the remaining stud. Next..heat the bolt stud up at the engine case, douse with some oil and get the vice grips onto the remaining stud and work it back and forth to get it moving. Work it out more and more and just use the vice grips to turn it out.

[Ledyard]

Thanks Chuck!

Here is a shot of the front of the carbs. Not sure if I just have the bowls swithched or not, but I'll check them out.

http://s1340.photobucket.com/user/Ledyard61/media/null_zps162f8c78.jpg.html?postlogin=true#/user/Ledyard61/media/null_zpsd4c1c562.jpg.html?postlogin=true&_suid=136984126694508143545690072997

[chuck hahn]

Look right to me. See if you can suck air from number 2 brass nipple. if so, that IS he number 2 carb. all others are in the right spots. Looks like maybe you just got the bowls mixed up.

[MisterCinders]

To sort out the 2 and 3 carbs, note the pilot air screw position. Those screws should point out, so No. 2 will have the air screw on the left and No. 3 on the right. In that pic the carb bodies are in the correct order.

[chuck hahn]

Yes...thats another way to tell. 3 has a BB in the nipple that prevents air to backflow UP the suction to the petcock..otherwise the petcock would get steady suction and it would be then pointless to have a vacuum operated petcock.

[chuck hahn]

Went back and looked at the MIXTUTRE screws and they are all in the correct spots. Just need to swap the 2 bowls around.

NOTE...I went and edited the response about the sprocket cover.......very important edit.

[Ledyard]

That's good news on the carbs.

On the sprocket cover issue, I hate to admit this, but like a true newb I snapped the end of a Grabbit tool off in the stuck, stripped, screw head. I'll see if a 3/16" drill will make a dent.

I get the concept of what you're recommending -- just not sure I can make it work.

Keep ya'll posted!

[eil]

Stay far away from easy-outs and the like. They're only good for causing more frustration.

Do you have an impact driver? Use one for all the screws on the engine and you'll likely never strip another. Then replace the screws with stainless steel bolts. (Z1 Enterprises probably sells a kit for the entire engine.)

[Ledyard]

Yep - I have learned the hard way to stay away from EZ outs, Grabits, and the like. All the other screws came out nicely with a couple of whacks with a Vessel JIS impact driver and rubber mallet.