Three Days In

[Lonerider62]

I've got three days into the new project bike (80 SG) and so far I've found a mouse nest in the air box

and some fine rust in all the float bowls. The faring wasn't what I wanted so it's off and I may decide to redo it at a later date but it will take quite a going over to remove a bunch of junk I don't care to keep. While getting the carbs off I noticed that Yamaha put a vacuum fuel pump on and I couldn't believe the rat's nest of hoses between the petcocks and the fuel rails on the carbs. I don't have my manual yet, but from what I can figure, on each petcock there is an outlet for the "on" position and one for the "reserve" position". Is that correct?

[jwhughes3]

octy

You found what is lovingly referred to as the octopus.

Standards have a vacuum operated petcock built into the petcock with a single outlet.Rather large.
specials used smaller petcocks to keep profile low I guess so vacuun diaphragm was moved to the octy. Search here on ways to eliminate it or just plan to put it back because you got to have a way to cut off fuel.

John

PS look for member Catatonic Bug and download a manual from his signature.

[Barnfresh]

Hey LoneRider... Nice looking Special.
Those little critters get in everything... Check your exhaust also.. Your air box does not look too bad - The mice had nested in mine so long the air filter element was all gone and the box was full of rust and mold. I threw it away and got another off ebay $10... Anyway - the critters bring in mold and moisture that can rust up the valve stems on open intake valves. If you have any intakes the have clearance > .020 pull the head and clean them up. Compression check too can indicate sticky valve that can mate with it's piston when things get spinning fast.
Good luck with your restoration.

[DGXSER]

The Octy is an added fuel shutoff for when the bike is not running. On the Standard models, the petcock does nto have an off position, so you rely on the vacuum valves to turn off the fuel. On the Special models, the petcock has an off position. So you can simply manually shut off the fuel when not running, and eliminate the Octy and all its fuel lines. You also eliminate the need for prime, so you can plug the forward outlets of the petcocks, which is the PRIME outlet. Then run fuel lines from the rear petcock outlets to the fuel inlet Ts on each set of carbs. You may also want to install in line fuel filters in the lines either way.

[Lonerider62]

The further I get into this project, the more worried I get. When I have started and run it, I didn't dee any smoke, but when I pulled the plugs and looked in the holes, the top of #2 piston looked a little wet??? The vacuum for the advance was just hanging between the carbs and the block so that may be some of the reason it ran rough at low RPM. But my biggest job now is valve lash. Every single valve was Tight and some TIGHT. The readings were as follows, #1 to #4: intake, .038, .051, .102, .102: exhaust .127, .152, .127, .127. All in MM. I tried to use te motion pro tool and could not master the damned thing even after reading every post I could find. Seeing how I have to replace every single shim and it doesn't look like it's likely I'll be using any of the ones in the bike, I'm going to pull the cams. I honestly think that will be quicker. I believe I saw a post that someone suggested getting shims that were much cheaper than Yamaha's. Does anyone know a source that's affordable?

[bikerphil]

Valve shims...

http://www.newmotorcycleparts.com/motor_parts/valve_shims.html

[crazy steve]

Personally, I prefer to pull the cams out, particularly if you're going to be changing all the shims. Keep in mind you may not need to buy a full set of shims; I was able to swap around what I had and ended up only needing two...

As to the MotionPro tool, some of those need mods to fit right on a XS, you may be one of the 'lucky' ones that got one that needs some grinding on it to get it to fit.

[XS1100_OEM4ME]

Mm

The MM tool will work fine on all the valves, just did mine a while back. What you have to do is rotate the cam till it moves the lifter "JUST BELOW" deck hight, not all the way open. Then position the tool on place and "if needed" back the cam (turning AWAY from the bottom of the tool) out till the tool drops in place. Line up the bolt and tighten down, move the cam lobe back to completly opposit the lifter, pop the shim out with a small jewlers screwdriver and pull out with a magnet or needle nose pilers, adjust size, turn cam lobe back down pushing lifter just below head deck hight again "MAKEING SURE YOU DONT" push the tool into the head, Remove tool, go to the next one and do the same

The further I get into this project, the more worried I get. When I have started and run it, I didn't dee any smoke, but when I pulled the plugs and looked in the holes, the top of #2 piston looked a little wet??? The vacuum for the advance was just hanging between the carbs and the block so that may be some of the reason it ran rough at low RPM. But my biggest job now is valve lash. Every single valve was Tight and some TIGHT. The readings were as follows, #1 to #4: intake, .038, .051, .102, .102: exhaust .127, .152, .127, .127. All in MM. I tried to use te motion pro tool and could not master the damned thing even after reading every post I could find. Seeing how I have to replace every single shim and it doesn't look like it's likely I'll be using any of the ones in the bike, I'm going to pull the cams. I honestly think that will be quicker. I believe I saw a post that someone suggested getting shims that were much cheaper than Yamaha's. Does anyone know a source that's affordable?

[Lonerider62]

Thanks a ton for the info on the shims. The place is in my favorites now. That will save me about 75% on the shims. At Bike Bandit they were $22 each. As to the tool. I think it's one of those things where having someone to show you exactly how the thing fits and how to work it in place would be invaluable. That's again to all who replied. I'm truckin on.

[Danny Crawdad]

Regarding the octy (which has been covered, but I'm doing it again ), I removed mine, ran Tygon fuel line from each petcock outlet into a "T" connection on each side, then from there into an inline filter, and then into the carb inlets on each side. Bam, rats nest gone, and remembering to turn it on/off is second nature once you do it a few times. When your bike drains the bowls after you forget to turn it on, you find out very quickly that you forgot to turn it to the on position! Also, the yellow Tygon looks cool .

Some like the octy because you don't have to remember to turn the petcocks off, but simplicity rules in my world . I turn the gas on, it flows. I turn it off, it doesn't.

[fredintoon]

Thanks a ton for the info on the shims. The place is in my favorites now. That will save me about 75% on the shims. At Bike Bandit they were $22 each. As to the tool. I think it's one of those things where having someone to show you exactly how the thing fits and how to work it in place would be invaluable. That's again to all who replied. I'm truckin on.

Hi 'lone,
if you are totally broke but have a friendly contact in a machine shop, there's a no-cost shim option.
Have the shims thinned down on a surface grinder.
Grind the side with the writing on it and mark the new thickness with an electric etching tool.

[DiverRay]

You can also send a PM to member WildKat, as she has control of the shim library. Send her the shims that you cannot reuse, with the sizes you need, and you should have them back via US Mail in just a few days.
Welcome to our sickness!

[Lonerider62]

Thanks again for all the great information. I was thinking about having the shims ground by a machine shop if necessary and checking what's in the "shim pool". I'm not broke yet but at every turn I see the bucks flying. I think the rear brake isn't bleeding back to the reservoir properly because after applying the brake (which works fine as far as stoping the wheel goes) the thing drags pretty bad.

[XS1100_OEM4ME]

Brakes

Check to see if the plunger in the M/C is sticking (especialy if the dust boot is missing) If not, remove and clean the spoge hole and everything else. If it is not leaking now, a good cleaning and reassembly should fix it And yes, welcome to our nightmare

Thanks again for all the great information. I was thinking about having the shims ground by a machine shop if necessary and checking what's in the "shim pool". I'm not broke yet but at every turn I see the bucks flying. I think the rear brake isn't bleeding back to the reservoir properly because after applying the brake (which works fine as far as stoping the wheel goes) the thing drags pretty bad.

[XS1100_OEM4ME]

Shims

Here is 8 shims for the price of one, with some spare lifters You can send him an email and ask for the sizes, if 2 or 3 help you now, might be worth it

http://www.ebay.com/itm/Yamaha-XS1100-Special-Used-Valve-Shim-Lifter-Set-1980-/150645457501?hash=item23132b425d&item=150645457501&pt=Motorcycles_Parts_Accessories&vxp=mtr

The further I get into this project, the more worried I get. When I have started and run it, I didn't dee any smoke, but when I pulled the plugs and looked in the holes, the top of #2 piston looked a little wet??? The vacuum for the advance was just hanging between the carbs and the block so that may be some of the reason it ran rough at low RPM. But my biggest job now is valve lash. Every single valve was Tight and some TIGHT. The readings were as follows, #1 to #4: intake, .038, .051, .102, .102: exhaust .127, .152, .127, .127. All in MM. I tried to use te motion pro tool and could not master the damned thing even after reading every post I could find. Seeing how I have to replace every single shim and it doesn't look like it's likely I'll be using any of the ones in the bike, I'm going to pull the cams. I honestly think that will be quicker. I believe I saw a post that someone suggested getting shims that were much cheaper than Yamaha's. Does anyone know a source that's affordable?