Grouchie's 1977 build thread

???

The crankshaft. Not the camshaft.

After looking at pictures I took of my service manual it looks like I was correct.
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The keyway to hold the Woodruff key (#24).
 
???

The crankshaft. Not the camshaft.

After looking at pictures I took of my service manual it looks like I was correct.View attachment 353704

The keyway to hold the Woodruff key (#24).
It is wherever it is. You can't change it's position.
You did get me to look at a couple of cranks. It is 180 from TDC on them.
 
I was just thinking were they smart and deliberately put it at exactly 180° from the crank pin? And not in some random spot. If so, then that makes things easier for everyone looking for TDC.
 
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Made a flange out of some "scrap" aluminum I "found" on my "lunch break" to test my cylinder head bolt pattern design.

I have been playing around with the idea to machine a billet aluminum 1-into-2 manifold with equal runners. I think I have a good design, and it will take a lot of work, and a welder to weld it together, but this is a start.
 
At last I think it's a good time to start reassembling things and make forward progress.

This is going to be a long read, be forewarned.

This bike was originally my Dad's. He had bought it brand new in '76. Fast forward a few years and my brother was born. I showed up a few years later. With two small boys and a mortgage, and as the sole breadwinner, money was a little tight for Dad.

He had come to an agreement with his dad that my Dad would sell him the Yamaha, on the condition that his dad was not to sell it, and that my Dad would work overtime and pick up Saturday shifts at the factory until such time as he could afford to buy the bike back.

So Dad worked long days, long weeks, long years, until such time as he had squirreled away enough spare pocket change that he could buy his Yamaha back.

In the one good deed that his dad did, he told my Dad to keep his money to support his family, and gave my Dad his bike back.

I remember Dad riding that thing on warm summer days home from work, down the alley to make sure me and my brother weren't being little hellions and breaking into parked cars.

Eventually Dad tucked it away in the garage, and it sat for maybe 15-20 years.

After I turned 18 and my Dad booted my ass from the house and he had spending money again and paid off some bills and debt, he decided to get the ole Yammie back on the road. When my brother and I were kids, Mom and Dad had a concrete slab poured in the backyard, and a basketball pole and hoop installed. Not needing the mini basketball court anymore, I remember Dad wheeling the Yamaha out of the garage, laying a tarp down on the court to not stain it, and working on the bike again, as he had done so often in his youth.

He got it running again, and it ran like a champ.

Once again, I remember Dad riding that bike to and from the same factory he had worked at for 35 years.

For years I offered to buy it from him. And for years he said no. Didn't say why, didn't even name a price. Just flat out refused.

A few years after I had moved to California from Illinois, he had finally had enough "fun" working at that factory, and being married, and packed up his truck and a trailer for his Yamaha, and moved to Arizona to go to where he called home.

Being a dry as shit climate, Dad simply parked the Yamaha outside. And sadly, that's where she sat, neglected once again.

Every Thanksgiving and every Christmas I would drive the 400 miles to see Dad, since I was pretty much the only family around. My brother was stationed overseas and while they couldn't be married anymore, my Mom and Dad were still friends. He continued to pay the mortgage and Mom's bills and shit like that, but as better friends than they had been in 20 years.

One day a few weeks before Thanksgiving one year, Dad calls up and asks if I had planned on coming to visit again. I said of course. He told me that if I wanted the Yamaha I could have it, otherwise he would try to donate it somehow, or take it to the scrapyard.

So of course I immediately jumped at the opportunity to have this bike that I had been trying to buy for years. I ordered a hitch for my MINI Cooper, worked late into the night to install it, and the next morning I had a trailer light harness installed.

Went and visited Dad, and as he helped me load the bike into the trailer, he handed me his old manuals and the title, wished me a safe journey and good luck with the bike. Gave me a piece of paper he'd typed out with some good parts vendors on it and said he'd gotten parts from a few of them.

Now, here is where I will throw out the fact that I had never ridden a bike before. I knew the theory behind it, clutch in, shift, clutch out. Repeat as needed. My first truck was a stick.

So back in California, I immediately start taking this bike apart to rebuild the engine.

Meanwhile, I take the title to the DMV and there was my first experience with the California DMV.

"Yeah hi I need to get this title in my name."
"Do you have the bike here?"
"No, it's in pieces at home, I'm rebuilding the motor."
"Then you don't have a bike, you have pieces of a bike. I can't transfer the title to you until you have a complete bike."

Ugh. Great so now I gotta throw the motor back in the bike, and have my buddy ride it to the DMV so they can fucking look at a complete bike. (Yeah I didn't have a Class M yet).

Get the title and a plate, and my buddy teaches me how to ride the thing.

From there I rode the thing for years, always tinkering with it, changing this doodad here, machining some part for it there.

Fast forward 10 years. I'm married, have a great job. Me and the Missus decide to take a vacation for our anniversary to Arizona to see Dad. On the plane ride there, I read a book about disassembling the motor to a level I had never done before, and I get the idea that that's what I'll do after we get back from vacation.

After vacation, motor comes back out, because I am bound and determined to get a good looking inside this thing, and also to make it kickstart only.

Three long winter months later, having not touched the bike since my apartment garage was unheated, my wife and I decide that "this place has really gone downhill in the past 8 years" and end up buying our first house.

One can only imagine how excited I was at the prospect of getting a 2-car garage all to myself. From there I stripped the bike completely apart down to the frame, and now the engine is in many pieces.

That's the history of the ole Yamaha.

What I want to do is turn this into a chopper. Not a chopper.... and hotrod on 2 wheels.

In the time I have gotten this bike I have learned how to TIG weld (when I say learn I mean I took a night class at my local college and zapped a few bits of 1/8 strip steel together) but more importantly, my CNC milling skills and abilities have improved a thousand fold. I have a key to the door at work, and the owners told me that even they are the owners, it's "everyone's shop". So if I want to stay late off the clock to work on personal shit, they could care less.

So my plan is to hardtail it, make it kick only, and add a springer front end. My Dad is entering his autumn years, and I would really like to make this thing a runner in his lifetime so he can "take it around the block" since he had told me he always wanted to make it a chopper himself but it wasn't a priority.

But first I need to get the motor back together. And that starts with me running to the store to grab some crankcase sealant.

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I have to admire your perseverance. I'm someone who gets bored and find that rebuilding bikes the perfect antidote. It might not be inspiration for you, but I note you said you would like to build a hardtail springer. Attached is a project bike in that vain. I've almost finished, made up from leftovers from several bikes, instructions gleaned from "Old School Choppers" handbook and a fair bit of impatience.
 

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Looking good!

I have discovered that reassembling things and worrying about the smallest of details has a certain peace to it. When I can go at my own pace (which is slower than molasses going uphill on a cold day) and not have a boss standing over my shoulder complaining about shit, I am at my most relaxed.
 
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Found my missing container of bolts.... AFTER I gave up looking and just bought new ones. :cussing:

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Got the clutch cover on and buttoned up.

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Plugged the starter hole with my custom made 2-piece plug. Hafta get some cam grease still and scrape the gasket off the starter geartrain cover.
 
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Alright so here's my dilemma. I installed the cam tensioner and adjusted the screw per my manaul so that the plunger is at most flush, and goes in just a bit when I cycle the crank using the kickstater. When I finger-tight the locknut, it doesn't bottom out against the cast aluminum plate. If I throw a ratchet and socket on it to bottom it out, it seems to be screwing the plunger screw in, because when I un-ratchet the locknut and take it off, now the plunger protrudes constantly.

No cap nut.jpg
No cap nut closeup.jpg

This is how my manual describes it being adjusted.


Fingertight.jpg

The cap nut finger-tight but still not seated.



Bottomed out.jpg

After using the ratchet the capnut is seated.


Capnut removed after bottomout.jpg

And now after I remove the capnut, the plunger is way out of adjustment, which, according to my manual, means there's too much tension on the camchain.

Some of you may notice I don't have the bolt in back for the rockerbox, I only have the cap acorn nuts tightened down to 25 ft-lbs. My plan is to make 3mm thick brass washers at work this week and then one at a time remove an acorn nut, throw a washer under it, and retighten it back down.

I read thru Jim's topend buildup, and I probably am putting a few steps out of order, but I noticed that his capnut had a sort of 2-piece assembly. Mine only has the one capnut, with an oring groove in it and no copper washer.
 
Need to determine if you have a type D or type E tensioner, or something else. On some, there's a lock nut and cap nut. On others there is just a cap nut. I think you'll have to remove the tensioner and see what you have from this thread -

Thread 'cam chain tensioners' https://www.xs650.com/threads/cam-chain-tensioners.1056/
 
It appears you installed the front cam chain guide AFTER the cylinders were mounted? If so, that's a no-no because you can't be sure if it's centered in the tunnel (at the bottom). Crooked front guides are rather common on these and it causes the side edges on the guide rubber to get knocked off rather quickly.

Best "cure" for those worn valve adjuster screws is to replace them with VW Elephant foot adjuster screws, but it requires a little bit of grinding to the rockers.
 
It appears you installed the front cam chain guide AFTER the cylinders were mounted? If so, that's a no-no because you can't be sure if it's centered in the tunnel (at the bottom). Crooked front guides are rather common on these and it causes the side edges on the guide rubber to get knocked off rather quickly.

Best "cure" for those worn valve adjuster screws is to replace them with VW Elephant foot adjuster screws, but it requires a little bit of grinding to the rockers.
I did not. Both cam chain guides were installed before the cylinders were mounted.
 
I've read about your issue a couple of times here on the forum (new cam chain so tight that acorn nut bottoms out on adjuster screw before it's sealed). Yet another "strike" against the type D adjuster, lol. The chain will loosen up rather quickly once run a little bit so maybe you won't need that lock nut for long. But I still think "upgrading" to the type E is the best option. I just bought another assembly off eBay to have as a spare, a "late" type E with the 59mm long adjuster screw and the 3mm thick rubber/metal damper washer. It's what I look for now. I don't get the "early" type E anymore unless it's really cheap, lol.
 
I usually try to save cash where I can by making my own parts.

I don't have a problem buying good parts, but sometimes the shipping fees are stupid. Not to mention most of the time I can just get it done quicker myself.
 
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