Topic: Terry's Redneck Yamaha XS650 build, the vibrator............

[Terry in Australia]

OK, so the Swamp Rat CB750 has a new owner, and I have a bucket full of cash, life is good.

I'm sitting in the pub on Friday at a work Christmas function, slightly bored, so flicking thru FB marketplace, and see an ad for 1980 XS650 that a young bloke has bought to build a sweet Cafe Racer/Bobber/Brat whatever, but like so many before him, he's gotten to the "pull everything off it, buy some new parts, then realise it's beyond your skill level, so leave it for a couple of years then sell it" stage.

The ad was a couple of days old, and he'd already dropped the price from $3K (AUD, about $2K USD) to $2K (AUD, about $1350 USD) when I saw it, so I was kind of surprised that it hadn't sold, because the old 650 Yam's are good bikes, and here in expensive Oz, $2K was cheap. On top of that, it came with some sweet spares, including some Brembo 4 piston calipers, an aftermarket MikesXS floating disc rotor (only one sadly) a new electronic ignition, new aftermarket blinkers and a headlight too.

I sent him a message to say I'd take it, not expecting much, because this has happened before, the item is sold but the seller hasn't bothered to remove it. Not this time, he got straight back and said "No worries, and I can deliver it to you for free". Nice! He couldn't deliver it on Friday, but he rocked up yesterday around lunch time, as promised. He was a nice young bloke, and happy to have a pocket full of beer tickets. I was happy to have a new pile of parts to put back on the road.

Terry's Yamaha XS650S 14 Dec 2019 4 by Terry Prendergast, on Flickr

There were parts in boxes and tubs, so I laid them all out to see what lurked within:

Terry's Yamaha XS650S 14 Dec 2019 5 by Terry Prendergast, on Flickr

This got my mental juices flowing, the bolt pattern for the 650 disc is the same as a CB750. Interesting............

Terry's Yamaha XS650S 14 Dec 2019 6 by Terry Prendergast, on Flickr

A company called "Pandemonium" sell an adapter plate to mount Brembo calipers to XS650 forks. XS650 forks are 35mm, just like CB750 forks. I need better brakes on my K2 "Bitsa" bike that I'm doing a rework on at the moment, so I ordered the adapter plates and a second disc rotor from MikesXS, in anticipation. I'm pretty sure I've got a Yamaha spoked wheel out in my garage, I must take a look at it.......

Terry's Yamaha XS650S 14 Dec 2019 Pandemonium Brembo kit by Terry Prendergast, on Flickr

Can you imagine how nice it would be to have brakes on a CB750 that actually work? I had an FZR1000 front end with 4 piston calipers on my "Goldie" K2 10 years ago and thought I was in CB750 heaven, so this will be very nice, I just need some more XS650 forks and an axle. More Ebaying..........

Anyway, back to the big black vibrator. Today I think I'll bolt all the missing parts back on to it, luckily Matt, the previous owner kept just about everything that came off it so if I can find all the nuts and bolts, it'll look a bit more like a XS650 Special by close of play today. Then I'll wait for the parts I've ordered from MikesXS to turn up, and then hopefully I'll have everything I need to put it back together. I don't know if I'll do much more with it, the "Special" wasn't my favourite with it's 1970's "Cruiser" styling, but I do like big twins, so it might be a fun commuter, or maybe a "Street Tracker" some time down the road...........

yamaha-xs650 by Terry Prendergast, on Flickr
     

[Terry in Australia]

So as previously mentioned, today I went out to start putting stuff back on it. As I mentioned, most of the parts and mounting hardware were saved by Matt, the previous owner (who stripped it all off) so I was able to bolt things back up once I worked out what was needed to do so. I had a little trouble removing the clip on handlebars as Matt had managed to strp the guts out of one of the allen screws, so I had to take my little dewalt angle grinder to it, to chop thru the bolt, but once chopped, it was putting up no further resistance.

I had to rat thru my CB750 parts to find the rubbers that hold the headlight ears in place as they're the same as XS650 items, so I eventually found some and modified them slightly, then found the correct rubber mounted handlebar brackets, the original handlebars, the new headlight (because the original was trashed) went in once I found some longer bolts, and finally the front fender, and the rear inner fender. By this stage my luck had run out, and I couldn't find the mounting hardware for the rear fender, so I opened a bottle of my "Mistle Toe" Ginger Beer, and forgot about life, for awhile. More tomorrow.

Terry's Yamaha XS650S 15 Dec 2019 by Terry Prendergast, on Flickr 

[spotty]

Here we go again, keep up the good work young man

[WhyNot2]

I'm in, watched the 750 build. Enjoyed it and will enjoy this one.

Good luck with the build............

If only I could nave some with my bikes.

[jgger]

Catcher's cup, hockey mask, shin guards............go get 'em Terry!

[MauiK3]

The previous owner even included a timing light!

[Just John]

We have a 1974 TX650 that has been in my wife's family since it was new.  I am the current "care taker".  It is stock with the exception of Shelby Dowd wheels which were installed in 1975. It was my brother in law's bike, he was the shop manager for the local Yam dealer in those days.  In 1975 he took my wife on a ride from the farm to her town job. It was 35 miles one way. She has not been on it since. She said it vibrated so hard that she couldn't feel her butt or feet for several hours after she got to work.

[754]

I have pretty much same bike, but way cheaper 1980 I think. I was pumped to get it, pushed it 7/10 of a mile, the first 1/2 uphill slightly with brake dragging ...ugh... Imagine my surprise when Pulled both cam end covers off and found no ignition !
 Anyway I planned a tracker, so I sold the stock tank, covers,  seat etc and now the bike is free.
 And I started building a aluminium tail section, but keeping back fender. Got stainless TT pipes from Hoos racing, tt are a must on a up right twin. And an aluminium Storz XR tank. I have much more for it like knock off wheels, maybe a Ceriani fork or at least Betors... not sure how much I want to sink into it
 Sounds like it should go to Oz .. lol.. will try to add pics later..

[Terry in Australia]

Hey thanks guys, when I didn't see any replies yesterday I thought that this might be one of those "tumbleweed" threads where the only person posting was the OP, so I'm glad to see there's some interest in the old Yammie 650's.

I've only ever ridden one once before, I think it was around the same vintage as this one, but with wire spoked wheels, and I do remember the vibrations more than anything useful like whether it had any grunt, or whether it went around corners etc. I don't want to waste those beautiful Brembo calipers on it if I can use them on a CB750, because with triple discs standard, the old Yam probably pulls up fine, compared to the less than wonderful brakes on my CB750, so if I can make 'em fit, that's where they'll be going.

Frank you're right, the "Street Tracker" look is the way to go if you want to modify one, although they also look pretty good as choppers, I've been watching tons of youtube vids of young guys cutting the rear ends off their frames and welding in a cheap hardtail section. One thing I don't like about them is the CV carbs, which seem to constantly come up in 650 threads as being problematic as they get old and worn. There are several options with carb conversions, but apparently Mikuni 34mm round slides seem the most popular. You can buy a complete kit from MikesXS for under $700 USD, or the manifold adapters and stuff if you buy the carbs elsewhere. I imagine this is for guys who have bought Mikuni knockoffs on Ebay, where these things are everywhere, for cheap.

I found a pair of genuine Mikuni's in my garage. I bought them years ago when i convinced Murray Feldman in the US to make a twin carb setup for my CB750K1. I still have the prototype, to Murray's disgust I didn't like the look or the performance of the conversion, but he must have gotten it right, as they are still selling thru a few shops in the US. No biggie, I have a great pair of 34mm Mikuni's to go on, which with the electronic ignition, should make for a pretty reliable ride. Hopefully............

Terry's Yamaha XS650S 14 Dec 2019 8 by Terry Prendergast, on Flickr

[spotty]

they're gonna find the amelia aerhart alive and well down the back of your garage one day

[754]

I am conflicted between chopper and tracker actually..soon any cool chopper XS s on instagram
Part of my plan was to cut the backbone downturn between carbs and move back about 5 inches, then use a Weber  or Dellorto 2 throat.. for several reasons .

[jaytee-nz]

You truly have an addiction Terry, but keep going mate as it's all very entertaining for us.
I've got the odd part from https://www.geoffsxs.com.au/OpenCart/ and found Geoff to be very helpful.
You've probably heard of him but just in case you haven't.

[bear]

they're gonna find the amelia aerhart alive and well down the back of your garage one day

Not true Spot, if Amelia is "down the back of Tez's garage" her remains are lost to human kind forever.
Come to think of it..........at the rate he's going he should work his way out to the front gutter by next Christmas. 

[Terry in Australia]

Ha ha, very true Brian, I need to find another shed, or sell at least 10 bikes. I keep saying that, but keep buying more projects, stop me, stop me before I buy again!

[Terry in Australia]

I am conflicted between chopper and tracker actually..soon any cool chopper XS s on instagram
Part of my plan was to cut the backbone downturn between carbs and move back about 5 inches, then use a Weber  or Dellorto 2 throat.. for several reasons .

Hey thanks for posting those pics Frank, yep, that bike's the same as mine, only nicer! So those are the stainless TT pipes? Do they poke out the sides so you can attach mufflers? Can you take a pic down low so I can see how they route under the engine/frame? Yeah a weber would be hard to install without modding the frame.

[bear]

At this stage in your life Uncle Tez the best thing you can do is embrace your addiction and go with it.
Don't change your life (Fcuk That) just upgrade your workshop/ storage space.

I managed to for stall my issues by purchasing a shiny new 40ft container that is now residing next to the 20ft container that I got sometime ago to solve my previouse temporary storage problems.

[scottly]

I don't want to waste those beautiful Brembo calipers on it if I can use them on a CB750, because with triple discs standard, the old Yam probably pulls up fine, compared to the less than wonderful brakes on my CB750, so if I can make 'em fit, that's where they'll be going.

Terry, swap to the F2/F3 forks, and make your own adapters to fit whatever caliper and rotor combo your heart desires. BTW, the Yamaha and Ducati rotors have the same 6 bolt pattern as our 750s, but the I.D. is 3mm larger, which requires an adapter ring to center the rotor on the hub.

[754]

Terry pull your cam ends look at the ignition...
 The Hoos pipes require a couple wields to secure the collars at head. They are pretty close together at the end , I think they angle out only slightly, but I would make megs to fit. Can't run center stand  looks like and it's close to 0il plug, but damn nothing looks better than TT pipes on those motors, I like the symmetry.  Had a set of Hooker TT,s on my CB 350  in the 70,s.
 Hoos pipes seem cheap compared to other pipes, but they are not polished.. actually looked like plain steel. And the TT can be run under the frame rails.
 Scott the 650 forks have similar mounts to 750F but different dimensions. Once you have that type of fork double acting calipers are fairly easy to mount.

[Terry in Australia]

Thanks Frank, I did take the ignition cover off and confirmed that it's the stock points, but I'll eventually replace them with the new MikesXS EI that came with the bike. Those pipes are cheap, I'll have to have a think about them, I have a nice pair of stainless megaphones that would look nice hanging off them.

OK, so I've decided that rather than shove all the bits into the garage in boxes and tubs, I'll try to bolt all the OEM bits back on. It's interesting that just about everything on one of these bikes is rubber mounted, the rear fender, the battery box, the footpeg mounts, and so forth. The only rubbers that were missing were the ones for the rear fender and the footpegs, so I decided to redneck something so I could make 'em work.

Years ago I bought some white plastic rod. I don't know if it is Teflon or Delrin, but it's been handy for little jobs like this. I chucked it in the world's filthiest lathe and using my shiny new chinese cutting tool, carved it into the shape and length I needed. I love this stuff, it's super easy to machine, but hardy material.

Terry's Yamaha XS650S 16 Dec 2019 by Terry Prendergast, on Flickr

So I made one insulator and it was a nice tight fit in the fender.

Terry's Yamaha XS650S 16 Dec 2019 1 by Terry Prendergast, on Flickr

Terry's Yamaha XS650S 16 Dec 2019 2 by Terry Prendergast, on Flickr

So I made another one, and was happy with the result.

Terry's Yamaha XS650S 16 Dec 2019 3 by Terry Prendergast, on Flickr

Well while I was at it, I made a pair for the RHS footpeg bracket.

Terry's Yamaha XS650S 16 Dec 2019 4 by Terry Prendergast, on Flickr

Terry's Yamaha XS650S 16 Dec 2019 5 by Terry Prendergast, on Flickr

OKay, so I did that, mounted the tail light and number plate bracket light thing, the battery box, the "sissy bar", the rear brake master and a few other little bits, and called it a day. Tomorrow's gonna get hot, so I might sneak out in the morning and get a bit done before it gets too hot, I'm already a bit sunburned from playing out in the driveway the last couple of days. That's OK, I do want to get it running, hopefully it won't reveal any engine problems, that'd suck..........

Terry's Yamaha XS650S 16 Dec 2019 6 by Terry Prendergast, on Flickr

[754]

When I pulled my cam ends off, nothing there, except a hole right through. I thought if yours was same you would enjoy that surprise ! On my motor, and fork I covered the first 3 letters of the name, it is now the AHA bike..

[Terry in Australia]

Ha ha, very good! Well it's gonna be hot today, so I'm gonna sneak out in a minute and take a look at the carbs and see if they need a clean. I may as well chuck them on and see if I can't get it running, although I doubt if I'll be able to ride it far with no seat and no brakes actually connected.

The seller told me that he was told that the engine had been rebuilt, but he never started it, so I'm interested in whether it's gonna be a runner, or a boat anchor. I did see some smears of gasket goo around the base gasket, so it may have had a top end rebuild, which, if done properly, will be a good thing, but if not, may result in a 750 kit and a hot cam. We'll see.........

[spotty]

before you run it, check the secondary oil filter behind the little round cover on the right hand engine case, they tend not to get cleaned at the same time as the other oil filter and can damage easily, when fresh oil gets flushed through the system it will clean out all the goop straight into the engine and expensiveness is ensured

ask me how i know this

[Terry in Australia]

Thànks Spotty, I'll do that!

[scrambler]

Cool bike you have there! I like these old Yamaha twins too, I have a TX750 from `73 equipped with the infamous omni-balance system to eliminate vibrations. Mine actually vibrates less than my CB750 K1. Good luck with the project and keep the posts coming!

[Terry in Australia]

Cool bike you have there! I like these old Yamaha twins too, I have a TX750 from `73 equipped with the infamous omni-balance system to eliminate vibrations. Mine actually vibrates less than my CB750 K1. Good luck with the project and keep the posts coming!

Hey thanks mate! Over here we have a TX750 owners club. I've always had a soft spot for them, in 1977 I owned the little brother, the TX500, so I wandered over to talk to a couple of the members at the Easter Broadford Bike Bash, and laughed when they told me that they thought about doing IQ tests on their members, but decided that they'd probably all fail. One guy here has a TX750 with a CB750 engine installed, you may have seen the pics? Nowadays they're quite the rare bike, I've even thought about buying one, but I'm not sure if I'd want to join that club?