Good! One of the neat features of the Discourse software.
Primary Chain Tensioner
Well, there isn’t one… and when the Hy-Vo chain streches there is an orchestra of clibity clangs… and if you leave it long enough it will eventualy start grinding through the top and the bottom of the case.
In the many years I have this bike there were several attempts to remedy this problem and fabricate a reliable chain tensioner.
It started, as just a block of very hard plastic, needles to sy it was usless…
.
Mark II was more elaborate.
Worked quite well, but the plastic (I think it was PPA) did not like very much the high temperatures and started defforming…
.
.
Mark III
Bits of steel and an old cam chain guide.
Problem was that the spring was mounted directly to the guide so the guide did not really follow the chain properly.
.
Mark IV
This last design really worked well!
.
2 Likes
Gunnar
It is NOT racist to suggest that motorcycles coming from Japan are inferior to motorcycles from another country. It is simply an old belief that equipment from an emerging manufacturing nation is not the same quality as equipment from a well established manufacturing country…which is…of course…no longer true.
Check out the definition of “racism”
RACISM
the belief that all members of each race possess characteristics, abilities, or qualities specific to that race, especially so as to distinguish it as inferior or superior to another race or races
Singling out “machines made in Japan and China” as borderline racist innuendo is, in my opinion, overly sensitive.
You would be better directing your attention to the propensity of your police officers to shoot innocent black people in America.
That is “racism”.
Aristidess
That is a great fix. What did you use as the contact surface on the chain.
My first bike too! Mine started with a full fairing kit and running boards on it. I took those off fairly quickly and bobbed the rear brake light and added a white stripe! I loved the feel of it. It’s still in my barn, I had started working on it became harder and harder to start. Turned out that I replaced the petcocks a few years prior with some cheap eBay ones and they basically rotted away in the tank in 4years!
I had upgraded my bike to a ZZR1200, so I wasn’t in too big of a hurry although I enjoyed riding both. 
my Zed with my massive self on it. I really loved my Zed. Instant power, smooth engine and great handling. Like I told people, you could pretty much ride 3rd all day as you could easily go from about 25mph to 130mph. I had it up to 148mph once and 100ish quite often when there was no one around and I could see clearly on both sides of the road. My riding days, at least for now, came to an abrupt halt on my way to work almost 3yrs ago now. I ALWAYS wore a fullface helmet, armored gloves and a riding jacket (at least a mesh with pads) and always jeans, and since I was on my way to work, I had on my steel toed boots with internal metatarsal guards. Needless to say I was doing about 55mph and came to the top of a hill where a road intersects. I let off and sure enough there was a car at the stop sign. I looked at him and he looked at me. I rolled back on the throttle and then heard his tires screech! He jumped through the intersection! I started to try to go around his backend then he really saw my and slammed the brakes in the middle of the road! I hit my brakes hard, but it was too late. Now all of this happened within 2 car lengths basically. I slammed into his rear driver’s side door, shoving it in about a foot, and twisting the rear wheel onto a 40deg angle. The impact spun his Dodge Neon 180deg. I was ejected and flew over the car and landed in the oncoming traffic lane HARD. I was awake for the whole thing and I remember clearly flying through the air, seeing the road coming up and thinking “this is gonna hurt!” I hit the road and obviously tumbled and flopped several times. I remembered someone said if you do down hard, pay the pavement with your hand to make sure it hits the same spot twice before trying to move, otherwise you could end up still moving and falling all over again. I did that then realized I was in the middle of the road and rolled/crawled myself to the side of the road. Lots happened after that, including me finding out the guy was riding on a suspended license and that the car he was driving had minimum insurance. Luckily I carried state maximum. My wife said she didn’t want me riding anymore, and I really didn’t want to put the family through something like that again. I still have days where I hurt more than others, but I still miss my 2wheeled therapy. My Zed after the impact. I figure I was doing about 50mph when I hit. It forced the forks back to the frame, buckled and split the frame on both sides, I bent both clip-ons (handlebars) forward, crushed the tank in with my legs and impact into it, snapped off the right footrest and lots of other stuff. Yes, after laying on the side of the road for a little bit I stood up and eventually hobbled myself to the ambulance. I found out, just this year that I actually broke a bone in my foot, but apart from that I had lots of muscle contusions and ended up having a bakers cyst form and rupture behind my knee forcing I’ve 80cc of fluid into my calf and foot. God was watching over me, and I’m absolutely glad that I was wearing the protection I had on
1 Like
Matt,
True. It is racist if someone were to believe that people from Japan and China are unable to produce a quality machine, by simple virtue of them being Japanese or Chinese. However, that’s not what Roger said, nor what he intended to say.
Roger and I have communicated in private, and I have apologized to him for being too hasty in drawing conclusions.
Gunnar
4 Likes
Sorry to hear your troubles Jason.
Had my fair share too…
You should fix that bike, it’s becoming quite a classic now.
Have plenty a parts if you ever need 
1 Like
Mine complete, just waiting for me to have the spare time and money to fix it back up again. Thanks for the offer!
That, and sheer luck: you were blessed.
Due to a riding event in my life, in 1977, where I held a friend in my arms as he bled to death–from a head wound, because he wasn’t wearing a helmet-- I soon ceased riding bikes on the street.
Sheer luck, or like I said, God was watching over me, which ever works. I feel for ya. I’ve never had to deal with anything that severe, but I have known several guys that weren’t near as luck as me. 
I still keep trying to convince the wife from time to time to let me put a paved track in my yard lol. She says no
Did you not think about using a Bearing , like on cam belt tensioners 
Yes I did, but it’s a chain and not a belt…
It would make a hell of a racket and I don’t know for how long the bearing could withstand this punishment before it turns either to thin dust, or in many many little pieces…!
Yes that’s true can see your point , can’t help but think the guide will have a very short life , I guess time will tell , and if you don’t plan on clocking up too many miles , it will do the job very nicely 
It’s made out of cam tensioner guides so it’s more, or less, made for this kind of application.
I have done about 2.000km and I didn’t see any obvious wear. Yes I do indeed hope it lasts…
Can you still buy a new unstretched chain from Yamaha? That’s a mighty wide, robust chain. Is it still available?
Is that a non-standard chain?
It’s a multi link chain, called UV something or rather…
Hard to find new and quite expensive.
And one of my intake valves is bent… not a happy camper.
Ah, that kind of slat chain: good luck.
Is that a Morse chain?
Aristides, I worked for Yamaha MC in the US during that time period.
I don’t remember any issues with that chain stretching. Plenty of other issues but not that.
So I would suggest a new chain might be a good move as your old one must be stretched excessively.
If that chain ever breaks you’ll likely ruin the crankcase. How many miles on your bike?
Also, I’d suggest checking the oil pump internal clearances, and shimming 2’nd wheel gear closer and tighter (.005" clearance) to its sliding gear if you have any issues shifting to second - before it eats a shift fork. If it pops out of second at all you might want to do it right away if you can find shims. And don’t powershift it, you might blow the cover off the 90 deg. trans to shaft drive gearbox. I still have a rubber ring shock absorber ring mod in my tool box for that one.
Interestingly, Yamaha sub’d the early gearboxes out to Getrag. My current BMW boxer has a decidedly agricultural shifting action. Un-Japanese snick-snick. You have to shift it like you have a pair! Getrag!
1 Like