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1981 XJ550 Maxim Rebuild-First Post/Progress, Advice Welcome

Discussion in 'XJ Technical Chat' started by XJ550FirstTimeBuilder, May 29, 2020.

  1. XJ550FirstTimeBuilder

    XJ550FirstTimeBuilder Member

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    Hey all, I've been lurking on these forums for a couple months, but i just managed to recieve a confirmation email today so i figured I'd make a post about my bike and ask some questions/try to get some discussion going. My thanks in advance for the help this forum has been also, I'd have been hooped on several major projects I've done on this thing since day 1 if not for this site and its users.

    Also, this is gonna be a long, long post. I'll be detailing everything I've worked on up until this point, where I plan to go from here with the build, looking for advice on what to do in order to save a bit of money (I'm a student and money is all sorts of tight), and the condition the bike is currently in/was in when I bought it *shudder*… previous owners in farmland are always interesting. If you make it to the end, I appreciate the read. If not, I totally understand. I'll post pics immediately following this post.

    I'll also mention that the garage I'm working out of is my father's garage, and he's been working on cars for the last 55 years (has completely rebuilt 2 1960's Studebakers including the one he bought at 16 years old) and they're kinda his life, so I have access to almost every tool I'd need apart from specialty, bike-specific tools. I'm located in Saskatoon, Saskatchewan, so having somewhere that's heated to store my bike is a godsend, as well as not having to buy a whole arsenal of tools to get the job done. I'm not too worried about revamping the rear suspension (yet) or anything, as I'm 125lb soaking wet and won't be putting much strain on the bike, though if it proves to have problems, it'll need to be fixed.

    First up, the bike was 700$. It starts, but that's pretty much all I can say for it. The front tire is flat and refuses to be reseated on the bead, and has cracks all over the sidewall. The bike ran when I showed up to purchase it, but leaked fuel/oil mix out of the airbox and sounded like it was drowning. There was no key set, since they were lost in the distant past, so all locks are currently drilled out and my key is a screwdriver. The rear tire was manufactured in 1961, and the carbs... well.. I'll get into that, but they don't inspire confidence for the rest of the bike's upkeep history. It was last registered 20 years ago, so that gives you an idea of what I'm dealing with. It has 18600 km on it, which doesn't seem too bad and leads me to believe that a lot of neglect/sitting has occurred in it's past with next to no maintenance, as opposed to someone ripping on it and beating the engine to death.
     
  2. XJ550FirstTimeBuilder

    XJ550FirstTimeBuilder Member

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    So far, I've gone to church on the carbs (mostly, will detail below), changed the fork oil and seals, have new carb boots on the way (the previous owner decided to coat boots 1 and 4 in liquid silicone to prevent leaks, I think?) taken off the old chain, scrubbed up/checked the rear brake shoes (the drum lever was rusted in position so the brake wouldn't disengage), checked the front brake pads (basically new), ground the paint off the tank in order to remove dents (have yet to remove them, but it's a start), cleaned the mouse nest out of the front sprocket (no joke), replaced the levers which were both broken, replaced broken turn signals, drained the 4 liters of thinner-than-water oil/gas mix and replaced with the proper amount of 10w-40 and a new filter, replaced the air filter which was a foam type but soaked with oil and gas from the overflow, and reconfigured the clutch pack (I couldn't afford new plates, but they seemed to be fine and got a 4 hour soak in fresh oil before they went back in the bike. The plates were out of order, and the boss spring was sitting pressed between the hub and pressure plate, not in the 6th friction plate's larger internal diameter. Thank you bigfitz52, your clutch rebuild post made my life a million times easier as well as reduced my clutch pull from the 20lbs it was). The cables have been lubed, and any moving part I can reach has been greased and all bolts are going back in with a thin layer of anti-seize on them.. The bike hasn't had a wash yet, as there was still half a foot of snow on the ground and -10 degree temperatures when the carbs came off and I refuse to let water into the engine, so I'm waiting for the carb boots I ordered off ebay to arrive before I can properly wash it since everything will be sealed up then, which will be followed by a regrease of moving parts.

    Now, the carbs have been giving me trouble since I got them off the bike. Carbs 1 and 2 (or maybe 3 and 4, I forget) each have a snapped float pin post from the previous owner, which was solved by a friend who does aluminum welding/machining for a living and has a a very exact eye, along with machined brass pins across the board (wood screws were what I found for float pins when I opened it up). The floats now consistently operate properly while dry and wet, with no binding or hanging up on the carb body. One of the floats was missing one of it's 2 black float portions, so a new float was purchased and all the old ones were tested to see if they actually behaved the same as the new float, which they did. New needles and seats, main and pilot jets, and float bowl gaskets were where my surplus from my tax return went. I'm sure my Yamaha dealer appreciated the 500$. The diaphragms are all solid, with no tears or pinhole leaks, though I have yet to clunk test the pistons which I plan on doing when setting the float levels. I didn't break the rack apart, as my dad explained to me that it'd be next to impossible to get them back together, but 4 cans of carb cleaner, some guitar strings, and an hour spent with compressed air later and the carbs are religiously clean. Currently, the only issues they have as far as my untrained eye can tell are that carb 4 has a starter plunger which is slightly extended, and rounded shoulders on the lower part of the plunger which leads me to believe that it may be snapped as it moves freely and isn't stuck, but I haven't yet replaced it. Cylinder 4 was running incredibly lean previously, based on the spark plug condition and especially in comparison to the other 3 cylinders, so I'm not sure what's going on there. Clunk testing still needs to happen but that's just laziness on my part (for shame, I know...) but the REAL fun has been setting the fuel levels. Using a level and a flat ruler to try to get them set seems to just introduce too many variables and opportunities for error, especially with one of the float bowls' drain screw head being completely stripped (that screw is being replaced in a week when the part comes in from Yamaha), so I designed a bracket that can be held onto the float bowl edge with string/elastic bands which has a protruding lip for spec measurements and places to slot the fuel hosing into (I'll post a pic of the design in the picture comment after this rant, if anyone wants to 3d print it as I am, feel free to). Once that bracket and the drain screw are both mine, the carbs will be finished that day. the mixture screws are set at 2.75 turns out, and I have 4 vacuum gauges which just need proper fittings and hose so that I can connect them to the carb boots when they eventually arrive.

    I have yet to do valve clearances, as I'm wary to open the head up and risk breaking the gasket (I'm completely broke until who knows when, so ordering a new gasket is currently out of the question) when I'll be able to at least check and see if the carbs flood and the bike runs or not in a week or so. Once I've been a child and verified that the bike does indeed run (I won't be riding it or putting it in gear as there currently isn't a chain on it), then I'll be taking the valve cover and side crankshaft covers off to do valve clearances, cam chain tensioning, ignition timing, compression testing, and a full carb sync and tune, in that order. It may be foolish, but I just want to hear the thing run before I rip it apart in a different way.
     
  3. XJ550FirstTimeBuilder

    XJ550FirstTimeBuilder Member

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    Having said that, I'm unsure where to get a valve tappet (is that what the tool to hold the bucket down when doing valve adjustments is called?) and a YICS blocker, as well as any other bike-specific tools, so any advice there would be very helpful. I would have inquired with chacal earlier about it, but I didn't have an account and couldn't message him, and also didn't want to bother him by inquiring about pricing when I'm too poor to purchase at that time.

    My future plans for the bike are to replace the chain and both front/rear sprocket, as the chain was.... I wouldn't trust it for 5 feet, and I understand chains and sprockets need to be replaced at the same time as they're mated parts. My shifter is also very, VERY tough to move, with only a brief interval when I looked at the bike when it would actually click in easily with the bike off (I'm unsure if this is normal behaviour or not, and have a feeling it'll remain tough to move once the bike is running but will update as I work). Following that, the only things I believe I need to replace before the bike is road worthy and I can focus my meager finances on gear is tires (Shinko SR777's seem like the best bang for the buck, if anyone has any suggestions otherwise feel free to chuck'em at me!), new wheel bearings, and replacing brake fluid, cleaning the master cylinder, and replacing all hoses on the entire bike. Paint and getting the dents out of the tank can wait, I just want the bike to be rideable. I'm fine with waiting to replace the ignition/tank locks, as I can keep a screwdriver with me and don't intend on stopping anywhere and leaving my bike unattended as I only have around 15 hours of seat time from the last five years (my learner's license lapsed and I almost gave up on motorcycling due to a lack of funds, which resulted in my selling off of my gear due to being strapped for cash at one point) so I'll be riding around my parents' neighbourhood to get familiar with the bike once I get my license and keeping it stored in their locked garage when it's not being ridden.
     
  4. XJ550H

    XJ550H Well-Known Member Premium Member

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  5. XJ550FirstTimeBuilder

    XJ550FirstTimeBuilder Member

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    I don't need a tool to do shims? When i read it, i thought he bolted something onto the head so it kept the lifter depressed. I may be reading it wrong though.

    Thanks for the referral to the yics tool post, I'll give it a look.
     
  6. XJ550H

    XJ550H Well-Known Member Premium Member

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    go to end you will see him use a wire tye or a piece of house wire no tool to bolt down
     

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