FixThe's 1981 XS650SH

fixthe

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Alright - so seeing as I'll probably end up working on and running into more issues with this bike than I originally thought, I figured it was best to start a dedicated thread to keep everything nice and organized.

So to introduce myself and recap, I'm from Winnipeg and have been riding for the three years. I have almost no mechanical knowledge but would like to learn, so I've got pretty well all the tools I need, a couple manuals, and people who can give me a hand when I need it. My first/last bike was an 80 XS400 Maxim which I loved to death but for a couple different reasons I wanted to sell that and switch to a 650, so in the last week I picked one up. Previous owner said that it was a 1980, registered as a 79, and looking at the serial number that looked right to me, but after posting photos here I've been told it's an 81 XS650SH, so that's what I'm going with. The bike looks to be in pretty good shape and has only 17,000 km on it.

According to the previous owner, it's mostly been sitting for the last decade and needed work, so before putting it up for sale he:

* Honed the engine cylinders
* Installed new piston rings
* Installed new engine case seals
* Installed new engine cover gaskets and head gasket
* Installed a new clutch cable
* Installed new cam chain and tensioner
* Installed new clutch plates and springs
* Set valve gaps
* Did an oil change

So far, I have put on new bars, grips and mirrors, new master master cylinder, HEL stainless brake line, replaced the headlight with a halogen bulb, double checked valve gaps, set cam chain tension and replaced the centrestand as the tang on the old one had bent.

For stuff I'll be doing in the near future:

* The old bucket looks like it's in good shape but it doesn't actually hold the light in too well, it wants to pop out. I've got a new bucket but can't solder and it looks like to take the bucket off I have to cut and re-solder the turn signals, so I'm going to get a buddy to do that for me. If I'm wrong about that let me know.
* I bought brass bushings and will be replacing the old ones when I have free time (probably after the ride season ends)
* Do an oil change - I've got a sump filter but am waiting on my oil filter to arrive
* Fix the carbs (more on this next post, just to keep this post from being incredibly long)
* Get some saddle bag brackets so I can move my bag back. I'd like to have bags on both sides of the bike but I'm not sure what people do for the seat release when they cover it with a saddlebag.
* Get new slimmer right hand control. The current one doesn't line up too well with the new M/C and it just bothers me a bit. Also looks like previous owner spilt brake fluid on it, so if I don't replace it I'll at least paint it.
* Grab a oil cooler - thinking of the MikesXS one. Don't really care about the dubious oil cooling claims, but it's a direct bolt in then I can grab the filter from anywhere instead of needing to order in.

Things I'm looking into doing down the line

* Grab a new clutch lever that matches the brake lever
* Change out steering head bearings to tapered roller - seems like most people recommend this but I haven't read too much on it yet
* Put in progressive fork springs - again, seems like a good idea but haven't read too much into it
* Get a new seat, paint tank, bucket, side panels, etc - The body of the bike is in great shape and it looks like it's been well taken care of, so any modifications I do visually I want to buy new parts so I can keep the stock ones and I don't want to do any chopping or welding. I don't love the seat but I don't hate it either so I keep going back and forth on that. For paint I'd love to do something like an old Camero - Nantucket Blue with white stripes down either side of the cap. It looks like a lot of work, but it looks like it could be a fun winter project to take on
* Possibly put in a new cam chain guide. There's a bit of a noise from the engine and when I had posted a video a couple people here said that it sounds like it could be that.

Alright, now for some photos. Pictures 1 and 2 are the bike when I went to check it out initially, 3 and 4 are how it is now, 5 is the right hand control and M/C, 6 and 7 show how I routed the cables after switching to shorter bars.

Think that's about everything - next post is my carb issues
 

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When I got the bike it seems to run fine up to 4k RPM, at which point the bike bogs and it lurches a bit until it hits 5k, then it comes back to life. Not really a problem going to and from work, but theres a couple speeds that are right in that RPM range - 80 and 100 km/h are the worst, so taking it out on the highway has been a no go.

I ordered in carb rebuild kits and new floats, then yesterday I went over to a buddies place to get him to show me how to clean and set up the carbs. Once we finished up and got them back on the bike it was in worse shape than before. We had a hell of a time getting it to idle but it was getting late and I had to get home, so we rigged up the throttle cable to give it a bit extra on idle, I was going to go home and get the bike back today. Driving home ended up being a nightmare. I kept having to give more and more throttle to keep the bike going, if I held my throttle open the RPM would jump up and down, I can't really describe the sound from the exhausts other than stupid loud and sounding like a dying animal, I was getting a darker smoke out of the left exhaust pipe, it was extremely slow responding to giving more throttle, the bike would sputter and jump and time I was decelerating, then it died on me at a stop light and it took great effort to kick back over. Eventually it went, I modified my route home to hit less stops, but the bike died again as I was slowing down to go into a roundabout. Again, it wouldn't kick over and many times there was no resistance at all on the kick lever. I thought about just ditching the bike for the night but I was in a bit of a sketchy area of town and didn't really feel comfortable leaving it there, so I kept trying to get it going which it eventually did, and I limped it home.

Possible problems or notes that came up last night and this morning:

* I had read that removing the cam chain tensioner acorn nut gives you a bit more room to get the carbs down and out, so I took it off. I loosened the chain a bit by accident as I was doing that and was going to re-set it once the carbs were back in, but I forgot
* One of the pilot jet screws was out way more than the other. We set them both back to 3.5 turns
* One of the pilot jet caps was missing. It's maybe possible that it actually was there and dropped out, but we gave a good look and didn't see it anywhere so I'm fairly confident that it wasn't there. We didn't have any on hand, so the guy I was working with quickly cut one out of rubber and we put it in until I could get a proper cap.
* The guy I was doing with showed me what do on one carb then I did the other. Once he had me going he went to do something else on my bike, then this morning he texted saying there was a washer left in the pan we were working in, so it looks like I missed putting the washer back in under the big jet

This morning I re-checked on the cam chain tension which was slightly loose but nothing to be concerned about (I don't think). I included a picture but it's hard to see, but there was a good amount of oil around the left spark plug. Also the plugs were super burnt, although that's not too surprising.

So, I've got a new baby at home and my time to work on stuff is extremely limited, so after work the guy from last night is going to come pick up the bike with a trailer and take it back to his place to get it going. If anybody has some insight on whats going on I'd love to hear it, or if there's any potentially stupid small thing we missed that I can check on before he picks it up. If not, I'll update back when he takes another look.
 

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I can't really describe the sound from the exhausts other than stupid loud and sounding like a dying animal, I was getting a darker smoke out of the left exhaust pipe, it was extremely slow responding to giving more throttle, the bike would sputter and jump and time I was decelerating, then it died on me at a stop light
Great write up so far. Wish I could contribute more on the carbs but those are newer than what I've played around with.
Can you put a timing light on it?
Easy to check that the timing is still correct.
Good luck -R
 
Hi fixthe,
good that you swapped out the stock 'bars. IMHO the list's Buckhorn Gang are mistaken in their preference.
You have to remove the front flashers to remove the headlight shell.
The signal wire.ends are small enough to fit through the shell attachment holes when they are unplugged.
And ANY damn fool can solder.
Clean the wires real good, twist 'em together, slather the joint with paste flux, hold hot clean tinned soldering iron underneath
the joint, feed flux-cored wire solder onto top of joint so it melts & tins it. After the solder cools slide the shrink-sleeve over the joint
(You did put the shrink-sleeve on first, right?) and shrink it with a hot air gun.
 
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When you said your plugs looked burnt, I expected to see them all white from running too lean. Instead, they're all black which indicates rich running. Your buddy helping you with the carbs, if he's not familiar with CV type carbs and 650 carbs in particular, he may be hurting more than helping you. Yes, you need the rubber plugs over the pilot jets or the bike will run rich. Float level is also very important. If too high then again, the bike can run rich.

If you left the washer out from under the main jet then I'm sure there will be issues. That washer allows the main jet to hold the needle jet in place. And speaking of which, did you remove and clean those (the needle jets)? Often overlooked, they can be quite crusted up. They have rows of tiny air holes down their sides and if plugged, again, the bike will run rich.
 
Can you put a timing light on it?
Easy to check that the timing is still correct.
I'm not sure - my system isn't the points ignition, if that makes a difference. I haven't really looked into this yet - just started then had to run out to work.
The signal wire.ends are small enough to fit through the shell attachment holes when they are unplugged.
So I should be able to simply disconnect the lights? When I was looking in there before it looked like they were soldered, but to be honest I was exhausted and may have not been looking close enough. I'll take a quick look again. About soldering - thanks for the advice. By "I can't" I more meant that I haven't and don't own a soldering iron. It's been on my list of things to buy for years, but I have a few friends who are into electronics so it's generally always been easier to give em a beer or two to come down and fix whatever I need.
Your buddy helping you with the carbs, if he's not familiar with CV type carbs and 650 carbs in particular, he may be hurting more than helping you. Yes, you need the rubber plugs over the pilot jets or the bike will run rich. Float level is also very important. If too high then again, the bike can run rich.

If you left the washer out from under the main jet then I'm sure there will be issues. That washer allows the main jet to hold the needle jet in place. And speaking of which, did you remove and clean those (the needle jets)? Often overlooked, they can be quite crusted up. They have rows of tiny air holes down their sides and if plugged, again, the bike will run rich.
I don't know enough about carbs to know the difference between CV and VM carbs, but I'm pretty sure hes got a grasp. I know he hasn't worked on a XS650 before, but in general I would say hes competent and I also trust him to find the answer if he doesn't know it, or to turn down doing it if he's not confident. He picked up new plugs this morning, so that should be good. For my own knowledge, what makes the XS650 unique? Or is it more just the type of carbs, which I'm going to read up on the differences.

As for float levels, we found conflicting specs. In the SH suppliment it says (IIRC) 27.5mm, but elsewhere we saw (again, IIRC) 22.5mm. Do you know what it should actually be?

Yes - we cleaned the needle jets. Everything seemed to be fairly clean already, but we gave it all another go through anyway.
 
Unfortunately, the manuals lagged behind the new parts that were installed. They didn't list the new spec for the new plastic floats that came along in 1981 until several years later, lol. That 27.3 spec they show in the "H" manual is wrong, it's the float spec for the previous 1980 brass floats. Your plastic floats should be set at 22 +/- 1mm. 22.5mm would fall in that range and would probably be fine. It would be slightly leaner and give a slightly lower fuel level in the bowl than the 22mm setting. The manuals also aren't very clear as to where on the floats you measure to. This excerpt from a Suzuki manual on basically the same carbs shows it quite well .....

fQoSj9N.jpg


On the sides of the float "bulbs", you'll notice a seam line from the molding process. When set right, that seam will angle up slightly from the pivot to the other end of the "bulb" .....

GCJ5MEF.jpg


With just a quick glance, you can tell if the floats are set OK, or at least close.

Did you happen to pull the needles and their assorted parts out of the slides? There is a specific order for the spacers and washers on the needle to be assembled, and for the location of the little spring (on top of all the spacers) .....

i3ZD5ra.jpg


Here's an actual pic. Disregard the added shim washer, that's a little mod to make things richer which you obviously don't need to do, lol .....

jC7c1HO.jpg
 
Unfortunately, the manuals lagged behind the new parts that were installed. They didn't list the new spec for the new plastic floats that came along in 1981 until several years later, lol. That 27.3 spec they show in the "H" manual is wrong, it's the float spec for the previous 1980 brass floats. Your plastic floats should be set at 22 +/- 1mm. 22.5mm would fall in that range and would probably be fine. It would be slightly leaner and give a slightly lower fuel level in the bowl than the 22mm setting. The manuals also aren't very clear as to where on the floats you measure to. This excerpt from a Suzuki manual on basically the same carbs shows it quite well .....

fQoSj9N.jpg


On the sides of the float "bulbs", you'll notice a seam line from the molding process. When set right, that seam will angle up slightly from the pivot to the other end of the "bulb" .....

GCJ5MEF.jpg


With just a quick glance, you can tell if the floats are set OK, or at least close.

Did you happen to pull the needles and their assorted parts out of the slides? There is a specific order for the spacers and washers on the needle to be assembled, and for the location of the little spring (on top of all the spacers) .....

i3ZD5ra.jpg


Here's an actual pic. Disregard the added shim washer, that's a little mod to make things richer which you obviously don't need to do, lol .....

jC7c1HO.jpg
Thanks for the info! That's what he came across yesterday about the brass vs plastic float spec and I believe that's where he measured as well.
I don't think we took the needle and all that apart, but I forwarded him this post just in case that would be helpful.
 
Bike is back to running condition! It's getting late here so my buddy is going to take it for a test ride in the morning, but things are looking good. Problems were found and corrected, bike is idling well, no more black smoke coming out of the left side. So heres what he found:

* The small pilot jets weren't tightened down all the way - that's on me. As you are all aware they are small and you can't really see in there so I didn't want to strip them. Thought they were good but should have asked my buddy to double check
* The washer he found this morning was in fact from under one of the main jets. Again (sigh) thats on me.
* One carb was missing a washer under the fuel screw. We didn't touch that yesterday so he hadn't noticed, but caught it today

So at the very least, the bike should be running as good as it was before we pulled the carbs, but hopefully this sorts out the higher RPM death!

Video of the bike idling

And fredintoon - you were right about the signals. The connectors were tucked away in the back and it looks like the left signal wire had been spliced at some point, as it's wrapped in electrical tape. I think I saw that and nothing else so I thought it had to be cut and re-soldered back after. Provided I get my bike back tomorrow morning I'll get my new bucket on some time this weekend!
 
Just got back home with the bike! Running way better than it was, but will still need tweaking.
Because the bike was never running properly, I'm not sure what's normal.

The good: All around smoother. It seems to be pretty even through the power and with no more engine bogging, once or twice I got some light backfiring on decel, but for the most part it feels and sounds good.

The bad: Needs to really be given the berries to move. Taking off from a start I have to give it wide open throttle. Once it's going it's fine but to really accelerate again - has to be wide open. Just cruising I need to be giving it more gas than I think I should have to.

The neutral: Engine braking is was down than it was. Prior to this if I was cruising along in third then I let off the throttle engine braking would kick in immediately. Not as strong as my XS400, but definitely noticable. Now it feels like it's almost not there - I let off the gas and it just slowly coasts. Also if I blip the throttle it almost hangs for a second then goes down much more slowly compared to before. Because I don't know how this bike should feel in tip top condition, I'm not sure if this is good, bad or doesn't matter.

Video of revs dropping. Sorry about switching orientation half way, wanted you to see my hand when I let off.

As the cam chain was adjusted I'm going to re-check my valve clearances tomorrow and do a quick sync on the carbs, then any advice on the poor throttle response would be great!
 

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Revs should drop quickly, like a rock, lol. Yours is hanging up. That probably explains the lack of engine braking too. The engine isn't slowing down quickly so it's not acting like a brake the way it should. Yes, check the carb sync, that can contribute to this. Hanging revs like that is often a sign of running lean too, or an air leak.
 
Revs should drop quickly, like a rock, lol. Yours is hanging up. That probably explains the lack of engine braking too. The engine isn't slowing down quickly so it's not acting like a brake the way it should. Yes, check the carb sync, that can contribute to this. Hanging revs like that is often a sign of running lean too, or an air leak.
Ah yeah - I wouldn't have described it as "like a rock" before, but definitely more than this. It was pretty intense on my last bike, so compared to that it was light but still there.

I've got some starter fluid so when I get home I'll give a spray around the boots and see if it's leaking anywhere. To me, exhaust pressure feels and sounds the same so I'd think the sync is close, but again - I'll check that after valves. If all of that is good and I'm still having the same problem should I be adjusting the pilot screws, or is there something else I should be doing?
 
The bad: Needs to really be given the berries to move. Taking off from a start I have to give it wide open throttle. Once it's going it's fine but to really accelerate again - has to be wide open. Just cruising I need to be giving it more gas than I think I should have to.
From the video and that statement.... sound's like it's only running on one cylinder.
 
Likely need someone who knows how to clean carbs. Like Jiom hints you likely have something plugged in an idle circuit yet.
And or the tank fuel lines are quickly recontaminating your cleaned carbs. That is WAY too common.
 
Hmm I don't *think* so but I'll double check in a bit. Went down to check my header pipes temperatures but they were both already cool.

About recontaminating - that's possible. There was no fuel filter installed and the ones that my buddy had weren't the right size for my fuel line, so that's on my list of things to do this weekend.
 
I noticed in your "current" pic you now have the alternator wiring loom run outside of the cover and chain guard? It shouldn't be like that. It should be in behind all that stuff and tied tight to the frame so the chain won't cut into it. It should also run under and get trapped behind the shift shaft guard. My '83 came to me with this loom routed incorrectly. It was tucked behind the chain as it should be but wasn't trapped in behind and below the shift shaft guard. This allowed the chain to cut into it and subsequently, it quit charging .....

PT0A2JD.jpg


It's all repaired and properly routed now .....

ySjlsqO.jpg
 
From the video and that statement.... sound's like it's only running on one cylinder.
Dammit, you are right. After two minutes of running the right pipe gets good and hot, left I can fully grab. Very slightly warm. The guy who was doing the carbs last night said that it was running on one, but he had it sorted.

5twins - I'll get that done this weekend, thanks for the heads up
 
Think I found my issue!!! Reading on potential causes for running on one cylinder, spark plugs and caps were listed as a possible problem. I was leaving work so I figured I'd take a quick look. Unplugged the left spark plug, plugged it back in, started the bike and gave it a little wiggle and press. Suddenly my idle jumped up to around 3k. This morning when I picked up my bike it was idling low so I adjusted it up. Did a quick balance and left work - the bike took off like a bat out of hell! Serious pull, massive acceleration. I think I commented before that I was surprised at the bike feeling underpowered. Now it feels more or less exactly how I expected, going from an XS400 to this.

Don't know if this can be fixed or if I need to replace the cap, but I wouldn't mind going to caps without a resistor in them. the resistor plugs can be found locally at any store here, where as the non-resistors cant
 
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I'd say you're in need of some new spark plug caps. I don't know what you have on there now, I can't see them clearly enough in your pics, but I can see the rubber boots where the wire enters the cap are missing. That's no good as it will allow water to run down into the cap where the wire connects. And obviously, the connection there is bad already, lol. Get some NGK LB05F caps. Don't get the "E" type that fit the terminal nut. The "F" type that fit on the threaded terminal stud grip better .....

CfYZoPi.jpg


Before installing them, prep the wire ends. Clip about 1/4" off to get to some fresh wire, then strip about 1/8" off the insulation and fan the wire strands out in a radial pattern like so .....

VqkZjYD.jpg


If you look into the wire end of your new cap, you will see what looks like a wood screw in there. The cap "screws" into and onto the end of the wire, so "screw" it on until it's tight. I also put some dielectric grease on the end of the wire before assembling it to the cap, and I put some of this grease in a few more spots to help seal the rubber boots to the cap and wire .....

J8LBimR.jpg
 
I'd say you're in need of some new spark plug caps. I don't know what you have on there now, I can't see them clearly enough in your pics, but I can see the rubber boots where the wire enters the cap are missing. That's no good as it will allow water to run down into the cap where the wire connects. And obviously, the connection there is bad already, lol. Get some NGK LB05F caps. Don't get the "E" type that fit the terminal nut. The "F" type that fit on the threaded terminal stud grip better .....

CfYZoPi.jpg


Before installing them, prep the wire ends. Clip about 1/4" off to get to some fresh wire, then strip about 1/8" off the insulation and fan the wire strands out in a radial pattern like so .....

VqkZjYD.jpg


If you look into the wire end of your new cap, you will see what looks like a wood screw in there. The cap "screws" into and onto the end of the wire, so "screw" it on until it's tight. I also put some dielectric grease on the end of the wire before assembling it to the cap, and I put some of this grease in a few more spots to help seal the rubber boots to the cap and wire .....

J8LBimR.jpg

Beautiful. Thanks for the pictures - I was going to watch a couple videos but I think that clears things up. I'll call around and see if I can get these locally anywhere, worst case scenario Amazon can have them at my house Tuesday.
 
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