'77 XS400 recently aquired

[Dutch Growler]

So I recently bought my first bike — a 1977 XS400. I think I have to do something with the handle bar bushings, as they're a bit loose, and it definitely needs tires, but aside from that everything seems to be quite right with this bike, which is in notable condition. There's just 9,000 miles on her.

Seeing as how it's my first bike, I was curious as to what people know about this biike, things to watch for etc ...

Also, it's an absolute bitch to get started but once it does everything's pretty cool.

Any and all advice/insight is much appreciated.

[Halvie]

I too just picked up a '77 XS400. Mine is in okay shape considering it's been sitting in a garage for 12 years (price was right = free!). I know I have some work to do, but she was running when she was parked, so it gives me a little hope.

I'm also interested in anything noteworthy on this bike (recalls, electrical gremlins, etc.)

If she doesn't have any major issues, I plan on modifying her to a cafe style, so if anyone has any hints, tips or tricks that may help with that direction, I'd be interested in those as well (I'll be searching the forum in the meantime...)

[Dutch Growler]

I too just picked up a '77 XS400. Mine is in okay shape considering it's been sitting in a garage for 12 years (price was right = free!). I know I have some work to do, but she was running when she was parked, so it gives me a little hope.

I'm also interested in anything noteworthy on this bike (recalls, electrical gremlins, etc.)

If she doesn't have any major issues, I plan on modifying her to a cafe style, so if anyone has any hints, tips or tricks that may help with that direction, I'd be interested in those as well (I'll be searching the forum in the meantime...)

where's all the help?

[Follyworks]

Sometimes the forum is a little slow to respond.

I've got a '78 xs400, been tweaking it out for a bit now. Biggest problem mine seems to have is with the ignition system. The old points systems keeps slipping out of adjustment, and when it does, it's a bear to start - that and making sure your carbs are clean are your most likely culprits on the hard start.

A common problem on the old xs400 is a revving problem - once it's warmed up, the idle speed will climb to around 3500 rpm. If you get happenning on your bike, hunt around here, how to fix it's been covered a few times.

[jordanscycles]

Well I have a '78 XS 400 and I just went through the carburetors, getting all 4 new jets and soaking everything in carb cleaner, oiling the slide, needle valve, etc. Now it's easy to start, dont forget to use the tuning screws... And when I had the 3,500 problem after riding and pulling the clutch in, I fixed it by simply turning the idle down a bit, just a bit. Slowly unscrew the idle screw until it stops, should happen suddenly. But it'll be my first bike too, I think it's a good one.

[mdsims]

So I recently bought my first bike — a 1977 XS400. I think I have to do something with the handle bar bushings, as they're a bit loose, and it definitely needs tires, but aside from that everything seems to be quite right with this bike, which is in notable condition. There's just 9,000 miles on her.

Seeing as how it's my first bike, I was curious as to what people know about this biike, things to watch for etc ...

Also, it's an absolute bitch to get started but once it does everything's pretty cool.

Any and all advice/insight is much appreciated.

adjust your points, that may very well fix the hard to start issue. That's what was up with my 77 xs400. I also fully rebuilt my carbs and added an inline fuel filter between the tank and carbs. A little piece of mind, that way I'm sure what's going on in the carbs...nice and clean now.

Post up a picture of your xs

[!!!MANIC Salamander]

So I recently bought my first bike — a 1977 XS400. I think I have to do something with the handle bar bushings, as they're a bit loose, and it definitely needs tires, but aside from that everything seems to be quite right with this bike, which is in notable condition. There's just 9,000 miles on her.

Seeing as how it's my first bike, I was curious as to what people know about this biike, things to watch for etc ...

Also, it's an absolute bitch to get started but once it does everything's pretty cool.

Any and all advice/insight is much appreciated.

Just found your forum here. I've been around the block a little with mine, and I may have some insight.

I will have two posts in a row. This one is copied from my review of the XS400D I mean to post on manicsalamander.com. The second one will be about issues of hard starting, and typical gremlins and solutions.

1977 Yamaha XS400D 32-year, 90,000 mile test

It was my first bike. They said in the magazines to keep your first bike, that you would regret not having it, so I kept it. It has always been my primary bike since I bought it in 1991, running mostly city commuter duty, as it was designed to do. It has been as far west as Gillette, Wyoming, and as far south as Raleigh, NC, and as far east as Boston. It has seen 500-mile days.

I ride it rain or shine, and down to 15 degrees, beyond which it will not start. I have ridden it on snow, dirt, gravel and sleet. I have carried up to two passengers, and up to 3 60-lb. bags of concrete. I have maintained it myself the whole time. I have personally sat on it for 80,000 miles. And now I am going to offer you my considered opinion of this particular machine.

I rode mine home in October 1991 with 10200 miles on the clock, for $300. By $450 total, it was shod in new tires, and had a rack from JC Whitney.

The generic description: Parallel twin of 398cc, four-stroke, air-cooled, two valves per cylinder, kick/electric start, 6-speed, single discs front and rear with single-piston sliding calipers, battery and point ignition with one point per cylinder, 180 degree firing angle, chain drive, suspension adjustable by shim and oil in front, preload only in rear, around 4” of travel front and rear, steel frame cradles engine, single downtube.

If tuned properly, with clean carbs and good ignition components, the XS400D can start about second kick, and idle like a clock when warm. The clutch is engaged by a lever screwing a very coarse-threaded nut with a ball on the nose into the pushrod. It is difficult to manage, with the tendency to grab after a few seconds of slipping. It also has a lot of stiction, so varying the slippage up and down dynamically is not precise. It only rivals clutches of more modern design when it is freshly lubricated.

The fussy, inflexible clutch aggravates a more positive characteristic, which is a very torquey motor. Acceleration off the line is very good for a 400, but it can feel explosive and difficult to manage for a beginner. I would sooner train a beginner on a 600cc four than this, because those are softer and easier to control at low revs. Idle is at 1250RPM. Smooth running can be had at 2500RPM and up. Power builds linearly to 8000RPM, where it is pointless to go further. There is no top end rush at all, though there is a little more beef between 6000-8000 RPM. Horsepower is modest, and better can be had from a 1979 KZ400 Kawasaki, or a 250 Ninja. You have no more acceleration than an economy car once you hit 60 MPH. The engine turns about 5500RPM at 70MPH, which feels busy, and vibration is significant.

The chassis is peculiar, in that it is a road bike with very limited suspension, but whose frame is constructed more like an enduro machine. The result is pretty decent, albeit bumpy, running on smooth gravel and dirt, with properly deflated tires, and a sort of floppiness and skittishness on pavement. The short suspension gets upset on average frost heaves and potholes, and bumps in corners will upset the frame easily. It is as if the road were degraded to a poorer condition when you are on this bike. Holding it in a lean requires constant countersteering or leaning off to keep it from standing up, though the forces are modest. There is an easily achievable lean angle where this situation changes, and the setup becomes very dodgy beyond that point. I have never gone far into that lean angle range. For brisk street riding, you are best served by a sort of seated enduro posture, elbows out, legs ready to support some of your weight, and being ready to use body English to fine-tune your line. That said, once you know how to talk to it, and become tolerant of hopping tires and being kicked off your seat now and then, it is flickable enough to really carve up the city streets.

The brakes, once you lubricate the caliper slider with silicone grease quarterly and install braided Stainless lines, are fantastic, and front/rear discs were otherwise unheard of on cheap bikes in 1977. The short suspension sets up quickly against the brakes, and serious deceleration commences immediately. This property lends itself nicely to urban duty, where early achievement of maximum braking is very valuable. Anything you dare to get into with that weird, floppy chassis and that torquey but wimpy motor, the brakes can take back with style. But remember, you need to do the work to make them that good.

My first trip was Minneapolis, MN to Davenport, IA, to visit a college friend. It shook so much that my hands felt like they were vibrating the next morning. Drag bars solved that difficulty. Later, bars similar to the original bend worked, with handlebar weights and a small windscreen so I didn’t have to lean into the wind as much.

Maybe the bike wore in, maybe I got used to it, but the vibration doesn’t seem so bad anymore. Even so, it can be felt all over the bike, and some of the parts have patterns worn into them from nearby parts rubbing against them for all these years. The JC Whitney rack is gone now, it vibrated apart many times, and finally wasn’t worth repairing.

This bike is one of those bikes that are lauded by their users for their reliability. But I think that needs qualification.

For its time, it was very reliable, by which I mean that if you did everything for it that the manual told you to do, at appropriate times, it would not fail to get you where you were going. It would not seep oil incurably, blow pistons, bend valves, shred camshafts, overheat, or fail to start if well-maintained.

The core electrical system is a miracle- in 85,000 miles and 16 years with no garage, the only failure of the charging system was caused by the seat pan rusting through, collapsing, and intermittently shorting one of the alternator wires to the chassis, interrupting charging. Nothing burned out as a result. Just repair the wire and seat, and go. I did replace the regulator just because the old one looked a little rough, at that time. Batteries last around 20,000 miles. In addition, it can ride through the rain interminably, without affecting running.

On the other hand, it has very short adjustment intervals, by modern standards. Points every 2000 miles, valves every 4000 miles. Carburetion is typical late-‘70’s, so the spark plugs need changing about every 8000 miles if you use the Bosch Platinum variety, fewer if you use normal ones. Normal plugs need to be swapped to cooler ones over 50 degrees and hotter ones below 40, to avoid problems. The single-piston sliding caliper disc brakes, while unbeatable in this application, require much more attention and cleverness to keep them at their best. Another understandable sign of its time is the electric starter, which strains to turn over the motor in the best of times. Below 40 degrees, it’s kickstart all the way. Also, if the battery is a little weak, using the electric start will depress the voltage enough that the ignition will not fire. But it’s a nice little perk for the good weather.

In addition, it is light-duty in its design. The tank is about 95 miles before reserve, and reserve is around 15-20 miles. I have had to re-ring it once and overbore it once due to oil smoke. It is susceptible to dropping out of fifth gear on occasion, and if this happens at full throttle, the resulting over-rev will burn the rings in one shot. That’s when the oil smoke starts. If you go 70MPH all day, you will start to use oil, and should check it every three tanks of gas to make sure. If you use it more lightly, the oil consumption is much less. I have worn out four clutch levers by wearing the pivot hole into an oval. The rear swingarm bushings are bronze and steel, and keep taking on water and rusting, and lack a grease zerk, so you need to pull them apart to lube them, probably more often than the 8000 mile recommendation. I turned myself a Stainless shaft and Delrin bushings, cut grease grooves in them with a dremel, and installed a zerk in the swingarm. Because I made them myself, I arranged for zero clearance in the pivot. This works mighty fine. No detectable stiction or play, and incapable of rust. For those not endowed with a metal lathe, just pull it apart and clean and grease it maybe every time you do the valves.

I would hesitate to call this bike a prima-donna, or unreliable. In fact it has, on several occasions, been the only bike in my stable that had what it took to go on a voyage, while other bigger, better-suited bikes were inoperable or could not be counted on. But it is quite high-maintenance by modern standards, and the attention it requires under heavy use is too much for anybody but a person who is happy to make lots of time for tinkering. Its parts cost per mile, not counting fuel, is worse than a 1983 XJ900 Seca, or a 1997 Kawasaki Concours.

On the other hand, armed with basic tools and a few rags, you can do a full tune-up at a campsite, as I have done many times. The valves are screw adjust, the crankshaft cover only has a tablespoon of oil behind it, and the points are right there on the side of the head. Only the gas tank needs to be removed for valve service. Valves and points together take only about 30 minutes, if you are practiced.

If you need to learn about how motorcycles work, and are prepared to put in the time, the XS400 will respond well to your efforts. It will reward you with a reliable, torquey ride that is great around town, and can head out on the two-lanes without trouble. It will give you fuel economy around 50MPG, which is better than most, but exceeded by the Kawasaki KZ400 of 1979, and Suzuki GS500 twins, Kawasaki KLR650’s, and Ninja 250’s, all of which have more power.

If you mean to log more than 4000 miles a year, or spend all your time on long trips, look elsewhere.

Even if you are right in the target market, that KZ400 is more powerful, handles better, is better on gas, has a nicer clutch, and has longer range. But due to the age of the machines, another factor comes into play; NOS parts availability. Yamaha owners are fortunate to have one preeminent and successful NOS parts warehouse at Speed ‘n’ Sport (www.yamatopdog.com) which has almost everything in one place. Kawasaki owners, especially of the small ones that are less fashionable, have to scrounge around a hundred websites where people are selling the contents of their garages. Your call.

How do I feel about the Yamaha XS400D?

Had I to do it again, I would have gone with a Kawasaki KZ400. But the XS400 is my first bike. It is my roots as a motorcyclist. I do not regret keeping it. Although I grumble a lot about the power and the short tank, and a bit about the handling and maintenance, there is much joy to be had from it.

I bought it because it was simple and easy to understand and fix. After all this time, I know every washer on the bike. I have already fixed every problem twice or more. This lends a sense of security out on the road that is hard to describe. I may need to get my hands dirty to successfully return from a long trip, but between me and the bike, we are hard to stop. It’s nice to feel needed and involved, and it’s nice to know that my efforts will be enough.

Also, as rusty and scratched up and unglamorous and wimpy and ungraceful as it may be, the lack of any particularly attractive traits in the bike seems to remind me of why I love riding so much. Absent anything attractive about the bike, I am left with only the basics to enjoy.

I get on. I pull out the enrichener. Two kicks, and it spins up. A sense of gratitude and excitement comes to me, understanding that this rusty piece of shit is once again about to deliver me one of the most joyful and miraculous experiences I have ever had, just like it has for 18 years. I turn the throttle gingerly and wait for it to clear its throat, push the enrichener back in, wait again for it to smooth out, flip it into first, and go. I feel the bike pull lumpily and unpretentiously away, and the world starts to move.

Some of my favorite blessings once again manifest in my life. I get to use and control all this found energy, the product of countless earlier beings living, collecting energy, and leaving it behind for me. One big twist of the wrist and more calories than my body could ever burn at once are at my beck and call, pulling me through the air, through the trees, through the traffic. Who knew a guy would be able to just buy 20 pounds of liquid energy and zoom away at unnatural speeds, to go anywhere? I could be so many places, so soon. I could be alone with trees. I could be laughing with friends. I could be hugging my sweetie. It’s up to me.

On my feet I am clumsy and slow. But my little bike and I, we can dance, and if you saw us, you would see the grace of many, many miles and years together shining, rather than nice paint and chrome. The joys of freedom and motion taste fine served raw.

[!!!MANIC Salamander]

So I recently bought my first bike — a 1977 XS400. I think I have to do something with the handle bar bushings, as they're a bit loose, and it definitely needs tires, but aside from that everything seems to be quite right with this bike, which is in notable condition. There's just 9,000 miles on her.

Seeing as how it's my first bike, I was curious as to what people know about this biike, things to watch for etc ...

Also, it's an absolute bitch to get started but once it does everything's pretty cool.

Any and all advice/insight is much appreciated.

Second post: Starting.

When I first got my bike, it seemed hard to start and reluctant to idle, tending to stall. It seemed to be very fussy about ignition issues. It also seemed reluctant to pull below 3500RPM, and lacked torque.

At first, I focused on the ignition. It was not enough. However, the ignition is not as strong as one might hope, and all of our bikes are old. For those reasons, I recommend y'all do the following things anyway, it is guaranteed to make your bike more reliable, and clarify what problems remain.

-Clean and polish every connection in the core electrical system with a Dremel buffing wheel and rouge, wiping the rouge off with a rag when you are done. You want all the following connections mirror-shiny, tight, and greased with dielectric grease. If a dremel won't fit, a small pocket knife is also good for scraping contacts. If you use emery paper, clean the connection carefully afterward so the grit doesn't stick around and compromise the connection.

-Battery

-Regulator

-Rectifier

-Stator

-Field Coil

-Fuse clips and fuse contacts

-Main key switch

-Kill Switch

-Coils

Fuse note: The bronze OE clips are likely to shatter in your hands. Radio Shack p/n 270-742 fuse blocks have clips that, with a little persuasion, can slide right in, replacing the OE garbage. These new clips are strrrong like Boool. They are subject to corrosion, though, so grease them. You can solder them to the wires or crimp them. Crimping is better, but spring for Ideal ratcheting crimpers, and insist on terminals that fit snugly over the wires you have. Compromise on either of these points and the connection will corrode or pull out.

Switch note: Old japanese switch gear is awesome. You can take it apart and clean it easily. Keep your hand cupped around it while removing any e-clips, and work on a clean table or cookie tray to capture stray bits. Just pull it apart slowly so you see where the springs, balls, and contacts go before they fall out. Basically, if you see a spring, it goes against a ball, or a moving contact. The other contacts are on a backplate of some kind. Polish the backplate till it is all shiny. Polish the moving contact, just so the parts that touch the backplate are shiny. Grease the backplate and any moving parts with dielectric grease, and put it back together.

Check spark plug boots for about 5K Ohms resistance. They unscrew from the hot wire. Replace if they are cracked or fail the test.

Replace plugs if over 8000 miles old.

Doing all this work is guaranteed to pay off in reliability. In extreme cases, it can double the voltage available to your ignition system, brighten your headlights, improve your battery life, and make it start when it wouldn't.

After 30,000 miles of babying the ignition system, which helped a bit, I finally stumbled on the missing link. Two things.

Clean the idle mix adjuster screws with carb cleaner, right on the bike. You do this by counting exactly how many turns you need to screw them in before they seat, writing it down, and then removing them, spraying lots of carb cleaner in, and replacing the screws. You seat them gently, then back them out by the right amount for each side.

Remove the throttle piston/diaphragm assemblies from the tops of the carbs, once again doable right on the bike. Look at the sky through the diaphragms, scrutinizing them for holes. Holes are most likely in places where the diaphragm folds. Since the diaphragm is reinforced with something like cotton fabric, Blue RTV silicone will stick to the cotton. If you work a little dab of RTV into small holes, it often seals them. My fix worked for 30,000 miles.

After this, my bike started easily, often without enrichener in the summer, idled like a clock, pulled cleanly down to 2500RPM, and had much more power down low.

Gremlins:

Swingarm pivot takes on water. Needs to be taken apart and lubricated. Lubricate the PIVOT and Bushing, don't stop at the axle that holds it on the bike. This can be done with the rear wheel and brakes installed, and the chain loose, by removing the pivot axle and tapping the pivot side of swingarm downward till it clears the bike on the bottom side. You then tap out the pivot, clean it all, then put the pivot back into the bushing.

Brakes are often weak and hard to control. See my review for the solution, which works a treat. A notchy, coarse feel at the lever needs a master cylinder rebuild. Not too hard. Lubricating any pivot points with automotive grease is good.

Shifting first to second sometimes doesn't engage, and falls into neutral, or makes shifting into third actually complete the shift into second. You learn to get the feel of it and shift twice sometimes.

Unit sometimes drops out of fifth into a false neutral. If you are accelerating when this happens, you can overrev. This burns the rings, causing oil smoke. For this reason, next time I need to work on the rings and cylinders, I am going to find or make a rev limiter.

Clutch mechanism is complicated, and should be completely lubricated at valve adjustment time, to perform.

You probably need lighter fork oil. I weigh 230, and settled on 15W. This improves cornering. So does changing it like they tell you.

Spring for a modern o or x-ring chain, when your current one goes. Replace sprockets with it. They are sooo much more precise and last like you wouldn't believe. I only have to check my chain tension every oil change.

Take the oil change interval seriously. Castrol 10W40 is good enough for 90,000 miles, but you feel coarser shifting as the oil wears out, so 2000 miles per change. Really.

Continental TKC12 vintage sport tires are awesome. Super sticky, but they only last 8000 miles in back.

If your bike wobbles on bumpy roads or in wind, it might be loose headset bearings, but it might be your own fault. The steering inputs are very sensitive, and when you start to get into serious maneuvering, you need to take care to support your own weight, and isolate your body movements from your handlebar inputs. Elbows up, arms bent, legs hugging tank. Then you can wring it out and really dance. If you sit back, straight armed, and try to turn, it will feel very insecure.

I hope this fills you in on the major stuff.

[drewpy]

excellent wite up and pretty much spot on with my ownership of this bike, although mine pulls up to red line ( well it did when i was racing an rd at wombwell). you can replaces the plastic swing arm bushes (original yam) with bronze type which last a lot longer.

to the forum manic

drewps

[!!!MANIC Salamander]

excellent wite up and pretty much spot on with my ownership of this bike, although mine pulls up to red line ( well it did when i was racing an rd at wombwell). you can replaces the plastic swing arm bushes (original yam) with bronze type which last a lot longer.

to the forum manic

drewps

Thanks.

To clarify re: swingarm bushings, my unit had bronze bushings, which were OK in themselves. My complaint was how the hardened/ground steel pivot gets water in the grease and rusts to the point that it locks against aforesaid bronze bushings, and then the system starts using the pivot bolt as the pivot, wearing on the bolt and the frame.

What I did was experimental and requires a metal lathe and much time. I turned a 303 Stainless pivot, whose finish was coarser than stock (a minus) , and turned Delrin bushings. With normal automotive grease, no moving parts can rust or freeze together, and the Delrin won't stick to anything anyway, it is very slippery. So far, so good.

For those with less of a wild hair, I was merely recommending a full disassembly and cleaning and regreasing at an interval at least as often as the book says, bronze or otherwise, due to the rustworthiness of the OE pivot.

[Cy Welch]

Thanks.

To clarify re: swingarm bushings, my unit had bronze bushings, which were OK in themselves. My complaint was how the hardened/ground steel pivot gets water in the grease and rusts to the point that it locks against aforesaid bronze bushings, and then the system starts using the pivot bolt as the pivot, wearing on the bolt and the frame.

What I did was experimental and requires a metal lathe and much time. I turned a 303 Stainless pivot, whose finish was coarser than stock (a minus) , and turned Delrin bushings. With normal automotive grease, no moving parts can rust or freeze together, and the Delrin won't stick to anything anyway, it is very slippery. So far, so good.

For those with less of a wild hair, I was merely recommending a full disassembly and cleaning and regreasing at an interval at least as often as the book says, bronze or otherwise, due to the rustworthiness of the OE pivot.

Fortunately the 80 models have both electronic ignition and regulators and have grease fittings for the swing arm so that problem has not happened for me.