81 XS400SH

Weezy

The Impatient Perfectionist!
Ok so here is my build. The idea started a couple of years ago when I decided to get a small ,cheap commuter bike to get to work. The original idea of a 50cc scooter was quickly scrapped which left me with finding a small displacement motorcycle. I figured if I could get a Japanese motorcycle from the 70’s and throw on a set of clubmans and a humped seat , It would be fun to ride and practical. My first problem was that I knew very little about Japanese motorcycles. My interests had always been on vintage European bikes.
So I started looking through the buy and sell ads and Craigslist. When I found a bike that looked promising I would look it up on the net to see if it was suitable. At the same time I found websites like this one to get ideas from. The two bikes that stood out for me was the SR500 and XS650. With all the great builds out there as ideas I soon had plans for a killer café racer .Then I realized I was building another full sized bike. I already have a vintage bike and I was getting away from the “inexpensive” part of the idea. So I sat down and made myself a list of what I really wanted.

-Inexpensive to buy!………….. I set myself a starting point of around $1000
-Cheap to insure!………………this one is the most important for me. In B.C. insurance is based on worth of the bike,(see above) and displacement. The range for me was 50cc-401cc.
- Single or twin cyld!………….I like the classic sound.
-Classic looks!………………..No cruisers or sport bikes. Dual rear shocks and a tube frame.
-Wire wheels!…………………Wire wheels always look good.
-Kick-start!…………………….Kick-starting your bike is half the fun.
-Chrome round headlight and gauges….They just look better.

After some searching I decided on a xs400. I have no idea why I leaned towards the Yamahas, I just liked them for some reason.
 
So eventually I found a bike that fit the bill on Craigslist. It was a 81 XS400SH for $500 and was only a couple of hours away. I got a hold of the guy to get more info. It had been a daily driver till a couple of years ago when he parked it in the garage. It starts and idles but backfires when you open up the throttle. He figures it needs new gas maybe a carb rebuild and a new battery. The front brake sometimes grabs. Oh yeh it also has 49000KM on it.
Well I was planning on rebuilding the carbs and resealing the engine anyway, so that’s no big deal .But 49000KM is a lot of K’s. I figured if it runs…. and at only $500 ….it was worth it if only as a parts bike. I borrowed a pickup truck, made a wheel chock out of 2X4’s and grabbed my tie downs. The guy said he had some boards I could use as a ramp. So on a sunny day I set off to pickup my “new” bike.
 
I arrived a little bit early as the guy was trying to start the bike. I heard it fire up idle then die. I walked over and took a close look at the bike. It was showing its age. The front of the motor had that dirty sandblasted look to it. The oil filter cover was obviously leaking a little and had coated the underside of the engine with oil and dirt. There was some major rust on the inside corners of the pipes and everything within a short distance of the chain was just as greasy as the underside of the motor. But otherwise looked OK. I suggested he let me try to start the bike and he agreed. He said his knee was starting to hurt. On the first kick it started up and settled down to a good idle. A good sign? :D After it warmed up I took it for a short drive around his condo complex. The front brake was not grabbing and I got all the way to 2nd gear. However it did occasionally make a loud backfire which kept me from wringing out the motor.
Here is what she looked like.
2009_0823xs400aug20090002.jpg

So we agreed on the price and I loaded the bike into the truck. "I guess I should get you the rest of the stuff." he said. Rest of the stuff????
He came out with a pair of well used but sill usable cordura saddle bags. He opened it up and pulled out 2L of engine oil, 2 new spark plugs, a spark plug wrench, a new Yamaha oil filter and a Haynes manual. Yesss!! Then he went back in and brought out 2 open face helmets. On his third return he brought out a brand new bike cover. This was the icing on the cake, he even let me keep the boards I used as a ramp.
 
So off I went home with a big grin on my face. I kept looking in the rear view mirror so proud of my buy. Now I should point out a HUGE irony here. A year a go if you asked me to point out the bike I hated the most, I would have showed you this bike. I particularly loath early eighties Japanese cruisers. They took their standard bike, added a couple inches to the passengers end of the seat, bolted on a sissy bar , pullback handlebars and an upswept teardrop tank. TaaDaa It looks just like a Harley…. NO it doesn’t.…Not even close, and they were all pained in that ugly purple color.
So the irony of how much I liked this bike was not lost on me. I also realized that I had given up some things from my list. Most important to me was that it did not have spoked wheels. Oh well I can always try to pick some up later.
I got home and unloaded it all. I call this picture “how much can you get for $500” ;D

2009_0823xs400aug20090009.jpg
 
Made out like a bandit. The way you were describing it, I was expecting a "swamp thing".
 
Ok this is where it gets fun. Part of the deal with me getting another bike was that I do some work on the house. Fair enough, so after a couple of months of painting I was ready to start tearing the bike apart.
By this time I had noticed that the break pedal had been pushed into the side of the case and had scratched a grove into it. It looked like the bike had been dropped at one time. :(I took the bike to work and degreased it. I had to use a scraper and a tooth brush and lay on wet ground with it being just above freezing. In the end though it came very clean. All that grease had done a good job of protecting the engine from corrosion. The calliper had started to grab again.
I drained the oil into a clear bottle that I had cut the side open on. The oil was very black. He hadn’t even changed the oil before he had parked it. In the end though this was a good thing. I then took out the screen covering the oil pump pickup. That’s when I found this!!!! :eek:

AlainasGradBanquet037.jpg
 
Hard to tell without more info, but it could be a piece of clutch plate, or a piece of camchain guide / slipper. I'm leaning towards clutch though judging by the (burnt) colour of the piece. Take off the clutch cover and have a look in there first before you try and start the bike again.
 
Congrats on the find. I have an XS360 cafe. These things make great around town cafe bikes. Looks like yours is in good shape, but if you are going to cafe it, you might want to look for a standard tank, The teardrop tanks don't work well for cafe lines
 
Thanks for all the comments. It helps to know that people are watching. Gives me a good incentive to keep going.
As for the bike itself , I like the idea of a 400cc overhead cam engine with a 6 speed transmission. Sounds like a race bike from the 60,s…..Well maybe if I close my eyes.
On the tank front I was planning on using a tank off a XS750 or 1100. They look more like a Norton Manx style of tank. But if you had to use the teardrop tank you could always paint it like a 1959 Norton Manx
http://www.asl-testsite.co.uk/motors/drawing/Norton-Manx500-1949.jpg
 
Well I was a little disappointed when I found the piece of metal. I knew what it meant but I tried to convince myself it wasn’t that bad. To me it looked like a fragment of a snap ring. It was smooth on both sides a quite flat and defiantly steel. Although the shape was wrong with the square corner. So I decided to sleep on it. By the next morning I had almost convinced myself that it was the end of a gear. Not just that but a gear that didn’t really need that piece anyway. ::)
So the next day I dumped the used oil into a container to take to recycling. During the night the oil had settled and on the bottom of the clear bottle I found this.
AlainasGradBanquet041.jpg

Not only that but small clumps of what looked like fine steel wool .S@#t!! :mad:
Well that’s that. No more trying to convince myself that all is ok. There is only one conclusion. My motor is toast! If a snap ring broke and went through the engine and all that is left is one chip,an ear and some filings then the gears and bearings must be severely damaged.
I was dejected for about a half an hour then decided that I would tear the engine completely down. I had no choice really. After that I wasn’t that upset. I have done top end work on my other bike, heads, carbs, ignition, but I have never torn an engine down to the crank. I was always worried I would wreck something and cost myself lots of money. Now I have nothing to lose. I only have $500 into it and I can’t make it worse. Now I am actually looking forward to it. Plus there is that small possibility that it might be salvageable.
 
So with some misplaced optimism I started to tear the engine down. You see now why I am glad that the oil wasn’t changed when the bike was parked. If it had been I probably wouldn’t know that the motor was on it’s last leg. So I took off the oil filter cover and found more of the fine steel wool. Great!! Its’ gone through the oil pump, that can’t be good. On top of that the service manual says when replacing the oil filter to not omit the spring and washer that goes over the bolt. What washer? There’s a spring but no washer. Also the cover is round with a couple of fins sticking out of one side. The fins point down and almost touch the frame. They were so close that I stuck a sheet of paper between the frame and fins to see if I could pull the paper out. I could pull the paper out so they were not touching but I fond if I rotated the housing 180deg. the fins fit perfectly into a grove cast in the block. So not only did the last person in the engine forget to replace the washer they put the housing on backwards.
After this I took off the final drive cover. I couldn’t clean the grease out of this when I degreased the engine so I had to do this now. I used a toothbrush and a pan of varsol. After working this in I sprayed it all down with brake clean. I love break clean , it’s a solvent ,it comes out at hi pressure, and 20 seconds later it’s completely evaporated. As I inspected the newly cleaned area I noticed a washer just sitting there on the shifter shaft. I pulled back the washer and saw a snap ring resting up against the seal. A quick check in the service manual showed that the washer should go up against the seal then the snap ring. Heck I didn’t even need the manual to tell me that. The final drive sprocket is held on by a nut and a bent over lock washer. But I could move the sprocket without moving the shaft it was on. The nut was not even torqued down. Luckly there was no damage.
 
The alternator and starter came off just like the manual said. I then went to the primary side and took the cover off. I took out the kickstart shaft which is supported on one side by the cover and by a boss cast on the inside of the block. The shaft looked like it was in good shape. Then I looked inside the case……???????? What the hell ?????? S&%T…S&%T S&%T S&%T!!!!!!
crankcase001.jpg

The boss is completely shattered. If it was just one crack I might think about welding it but at this point I don’t think it’s worth it. Or even possible for that matter.
Also on this side of the case I found another corner of the snap ring.
 
At this point I feel like I’m on CSI trying to find out how the engine died. I took the clutch off and found where the snap ring came from. Actually it was still here but with both ends missing. Which still leaves me with the first piece of metal I found. It doesn’t fit into this snap ring at all.
I think hillsy has it right. It probably is a corner of clutch plate. It makes perfect sense now. I wonder if it is a leftover from a past clutch failure. My plates all look in good shape. But , taking a look at the manual it shows a washer between the broken snap ring and clutch housing. Guess what? NO WASHER!
Next I removed the two clutch pushrods then removed the oil pump. This was enough for now so I called it a night.
That night I read through the manual and discovered something. ONE clutch push rod not two. Somehow mine had snapped in half and rubbed against each other. I wonder if this explains the fine steel wool?
:-\
 
I’m back! :D Sorry I find it hard to sit myself down and write sometimes.
Ok so next was the retainers for the shift drum. The manual said that the screws were soft and a concerted effort was required to remove them. Well they weren’t kidding. I think they were made of silly putty. So after rounding out the Phillips heads I used a small vice grip to remove one screw and twisted off the head of the other. Great!!
 
So next was the top end. All went well till I came to the Dome nuts that hold the head down. Beneath the nuts are a copper washer.
xs400teardown017.jpg

8 dome nuts , 7 copper washers and one steel lock washer.

It’s official!! The guy who put this engine together is a idiot! Does he have something against washers?
 
Here are some pictures of the broken snap ring and my “2 piece” clutch push rod.
xs400teardown002.jpg

xs400teardown018.jpg
 
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