Bought on Bike-urious – Rebuilding the Triple, Part 2

In Bought on Bike-urious by Cas VanderwoudeLeave a Comment

Share Button

Editor’s Note: A few months ago, I featured a Yamaha XS750 with lots of period goodies that needed a lot of work. When I concluded the post, I said “I hope someone brings this bike back to life. Will it be you? ” Well, apparently contributor Cas Vanderwoude decided he would take up the mantle. Even better, he’s going to be sharing his trials and tribulations so we can be entertained by his suffering:

Missed Chapter 1? Cas talks about how to prepare “for the arrival of your new baby.”

Chapter 2: “The eviction”

The Yamaha Triple, finally in my garage.

After some transportation hiccups at the seller’s end, the Yammie Triple finally arrived home a few weeks ago, and I was keen to make a start. So, how does one go about this? Everyone will have a different approach. The scripted motorcycle rebuild television shows normally start with a frenzied pull-down of the entire motorcycle, leaving only a cruddy frame left on the stand. Then we are guided through an artificial “restoration” process interrupted with a choreographed crisis of sorts where some irreplaceable part is missing or gets broken, necessitating a nation-wide search for a replacement. The final segment shows the finished product starting first kick and the builder rides off into the sunset. Now that’s fine for a TV show, and in modified form, maybe how a professional restoration job might be done…it’s also a good approach for restoring something that is in really bad shape. But for beginners and enthusiastic amateurs like myself, there is another way to go about things. I call this approach: make it run, get it running right, then decide what to do. This step-wise approach helps me focus on essentials first and stops me from fixing problems that don’t actually exist. The minor downside is that you might end up doing some things twice. It also gives me a chance to get to know the new addition to the family before I decide on what the finished product might look like. This triple is a really good example of why I want that time to decide – it is actually rather nice in a retro 70’s way, with that huge fairing and already distinctive look.

Luckily for me (and you, if you, are thinking about something along these lines), 1970’s Japanese motorcycles are mostly over-engineered and very solid. The two big weak points on these (and many older motorcycles) are the electrics and carburation. The bottom end, transmission and clutch are usually fine and will not need any work. So, how to make a start on the old girl. Well, first, go out and buy some JIS cross-head screwdrivers. All Japanese motorcycles and most Asian electro-mechanical things are held together by Japanese Industrial Standard (JIS) cross-head screws and bolts. These look just like Phillips head screws but they are not. Phillips head screws are designed to “cam-out” at a predetermined torque while JIS screws allow the user to decide how much torque to apply. I DID NOT know this. For many years I thought the fasteners on Japanese motorcycles were just poor quality. Turns out, that although phillips-head screwdrivers look the same and can be used on JIS, they have a nasty habit of doing what they are supposed to do – cam-out at a predetermined torque. I’m sure this has resulted in BILLIONS of stripped out screw heads over the decades! Cheap but useable JIS drivers can be had for around $22 a set from Amazon, or better yet, visit the Vessel website for a larger range and better quality. (At least one of you readers out there will thank me for this tip). A clear explanation of the differences can be found in this YouTube clip.

Back to the job at hand…there is a fairly standard checklist for an older motorcycle that has spent a decade or more unused in a garage somewhere. Do these things before you even think about pressing the start button or kicking over the engine:
1. Change ALL fluids – engine oil and filter, brake fluid, fork oil, coolant, transmission and final drive (if applicable). In this case, the Yammie has a final drive and a “middle gear” so don’t forget to look for these. If the motorcycle has discs, and the master cylinder is not as effective as you like, do not buy an overhaul kit – get a new MC – even if it is a cheap generic one like this. I’ve never had any luck with rebuilding master cylinders. Often, the cylinders are corroded to a point that no amount of honing, cleaning and new seals will get them working properly. I figure a cheapish new one is better than a leaky defective genuine item. Measure and order replacement hoses. Brake lines soften over time and this allows them to expand when pressurized which severely affects the ability of the caliper(s) to grip. There are eBay sellers who will custom make cables to suit your needs. Use cheap engine oil (30-40 weight without any friction modifiers). You can use that as a “flush” oil which should be changed after a few 10’s of miles.
2. Remove and clean the interior of the gas tank (dismantle and clean the petcocks). If the tank is badly rusted or has pin-hole leaks, there are good quality sealers available. The best around is made by Caswell which is the only one to use on fiberglass or resin tanks. Older fiberglass tanks will not hold the new ethanol gas. Another good sealer is Red Kote.
3. In the meantime, put the tank one side and use a portable shop tank. I cannot comprehend why these things are so expensive, but they are much safer than any temporary thing you might want to rig up. While I’m on the subject, buy a small fire extinguisher suitable for gas fires. Keep it within arm’s reach. One day you WILL use it (trust me).
4. Install a fresh working battery and make sure the terminals and connectors are nice and clean. Liberally coat the terminals with dielectric grease.
5. Replace the spark plugs, HT leads, spark plug caps, fuel lines. At least check all the rubberish bits, inlet manifolds, vacuum lines etc to make sure they are not holed.
6. Check the fuse box and at the very least, clean the connectors and make sure the fuses are still ok. Better still, replace the fuses.
7. Lubricate control cables and check they all operate properly. Older seized ones can be hard to lube. The best tool for the job is a “Doherty” type hydraulic cable oiler. A bit fiddly but they do the job very well. Speedo and tach cables should also be lubricated. Replacement cables are very easy to source and usually not expensive.
8. If your motorcycle has a points ignition, check and set the timing (and order a new replacement and a new condenser for later, or better yet, find an electronic replacement unit).
9. Remove and replace the air cleaner. I’ve had some projects where the filter turned into a fine powder just by touching it. You do not want to start a bike with an old filter in place.
10. Tire compounds gradually harden as they get older. Really old rubber becomes as hard as a rock. Check the tires. Any tire more than 10 years old WILL kill you. Any tire more than 5 years old is a bad idea but ok for a careful ride around the block. Every tire has a date code stamped on the LHS sidewall, made up of a series of letters followed by three or four numbers. The numbers can tell you when the tire was manufactured. Tires made after the year 2000 have a nice easy 4 digit code. The first 2 numbers are the week of manufacture and the last 2 numbers denote the year. So the code 2616 is for a tire made in the middle of 2016. Older tires have a three number code – just take them off the bike before someone gets hurt.

The tire on the top was on the Triple when it arrived. The last 3 numbers on the date code tell me it was manufactured in week 28 on either 1997 or 1987. I replaced it with a new Bridgestone S11 tire (bottom). The date code shows it was manufactured in week 14 (April) 2016.

Now you are ready to hit the starter. On a few lucky occasions, the engine will fire right up, but usually not. If it does, do not rev the clappers out of the engine. There will be no oil in the top end and many other places because the oil has not circulated for a while. Keep the revs low, check for smoke and leaks – oil, brake fluid, coolant and gas.

So, how did I fare? I picked up my new project from the freight forwarder in my truck, brought it home and walked it into the workshop. Rather than using the lift table, I just put the bike onto its center stand because I knew I’d be changing the tires and that is difficult on a lift table. Now to see what I had (cue ominous music). The first thing I noticed was there was a bit more rust than usual. No problem – nothing too severe. Then, I noticed the carbs were not clamped on the inlets. This means that someone, sometime recently, had the carbs off the motorcycle. Basically another person had tried to get the bike started. And that person was not successful. That can be a sign that there might be deeper and unexpected problems. (I checked the original images on the email listing and confirmed the clamps were missing at that time).

The tires were at least 20 years old, so these were replaced. Avon AM26 on the front and a Bridgestone S11 on the rear. The Avon AM26 are my favorite – they wear well, work great on classic bikes and most importantly stick well in the wet. As is always the case with old tires, the original tires were not easy to remove. With time, the compound hardens, and stretching it over the rims gets more difficult. Having the wheels off also gave me the opportunity to grease the splines on the final drive and lubricate the speedo sender. Bearings felt ok, but they will be replaced later anyway. The wheels need a good cleaning and repainting but that will wait. While I had the wheels off, I also took the time to carefully clean the discs with solvent.

The electrical system on 1970’s motorcycles are fairly reliable. Over time, the connectors become oxidized and this leads to most of the problems. Some preventative maintenance was definitely needed. I pulled all the connectors apart and cleaned them (a painting prep pen is rather handy for this and even better is a terminal cleaner set). Before re-connecting them, I injected the terminals with dielectric grease. This promotes a good electrical contact and keeps water and air out of the joints. I obtained some large hypodermic needles from my pharmacist and used these to dispense the grease into the terminals. A new battery and everything checked out electrically.

It is a good idea to disconnect every electrical connection, clean the terminals and apply dielectric grease during re-assembly.

The biggest job was cleaning and rebuilding the carburetors. Lucky for me I have an ultrasonic cleaner which helps tremendously. After ordering a carb rebuild kit, I dismantled the carbs and cleaned them thoroughly, assembling them with new gaskets, jets etc. The last thing I did was to screw in the mixture screws only to find they would not go. On closer inspection, I could see the tips of the old screws had broken off in the carb bodies (apparently a common malady for this model carb). After all my fastidious cleaning I had a shiny set of carbs that were not useable and not repairable. “Darn!” I said (or words to that effect). After some searching I found a replacement set which arrived quickly and bolted right on. On most older motorcycles, expect the cycle of carb dismantle-clean-assemble-test to repeat itself several times until all the passageways are clear.

A nice, clean and shiny carburetor. Unfortunately the tips of the mixture screws had broken off in the carb bodies rendering them unrepairable. Compare the old mixture screw on left with the replacement (right).

The last thing left to do was to replace the side stand (which had rusted severely and no longer returned) along with some minor frame touch-up. Clearly, when I decide what to do with the project, I’ll have to paint again, but I wanted to cover any bare rusting metal bits before riding. I see that powder coating is rather popular for frames nowadays. I think it’s a bit expensive and powder coat is rather brittle and prone to chipping. Being a cheapskate, I prefer to use POR 15 chassis paint. A very small starter-kit can be had for about $25. It contains the etching material, enough paint for a frame, a brush and detailed instructions which must be followed to the letter. When properly applied, it will last as long as powder coating for a fraction of the price. Use gloves when applying, the stuff sticks like shit to a blanket. Get some on your hands and it will stay there for several weeks.

During decades in storage, the battery had slowly leaked down the old stand. This caused enough corrosion to warrant a replacement mostly because the attachment point for the return spring had disappeared. A newly painted replacement stand is on the right.

Time for the big moment, a clean tank with some fresh gas. Press the starter and hope for the best. The old girl refused to start. I figured with vacuum carbs, the system might be having trouble priming itself, so I sprayed a judicious amount of starter fluid onto the air filters. To no avail, but I could hear the engine want to start. More starter fluid, more turning over but no go…all I managed to do was start a small fire (remember how I suggested we should all have a fire extinguisher on hand?). Motorcycle starters are fairly small and heat up very quickly. It’s best not to run the starter for more than a couple seconds at a time and after several attempts, give it a rest before trying again.

I was stuck – what could it possibly be? Some deep thinking was in order. My mind wandered back a few years to the time I dropped in to visit an old friend. As I arrived, he was kicking the living shit out of an old dirt bike he was rebuilding, when finally it exploded into life. I say exploded, because that is kinda what happened. A moment after ignition, a dead rat, along with the archeological remains of decades of previous rat habitation flew out of the muffler, narrowly missing my right ear. This is something not expected on an old road bike because the way mufflers are built, but the Triple had straight-through Jardine mufflers which means there is a clear path from the valves, all the way to the outside world. I removed the entire exhaust system off my Triple and sure enough, it was packed with mouse-houses and granaries from stem to stern. The bike could breathe in, but not out! Once cleaned, it started right up, received a Hawai`i safety certificate and registration and survived a 60 mile test ride.

I now understand why 3 cylinder engines have such a devout following. The sound is definitely addictive, especially with open pipes like this one. Here is a short video of the start-up if you would like to hear what I mean:

So, now it’s on the road, running, but not that well. It will be a long journey, punctuated with plenty bruised knuckles and new things to learn before I have it running well. So far, the cost has been under budget. I expect to add a $1,000 to the buy price of any motorcycle to get it where the Triple is now. So far, I’ve outlaid $531.00. Not bad.

Now I will start on getting it running well, but while doing that, I’m eager to hear what you, the reader, thinks I should do. There is a whole world of options out there. Anything from an oily rag restoration to a full-blown custom build. What do you think? Should the fairing stay, or go? I know I need more time to decide. But, at least while I’m thinking, I can get to ride the triple around…

Share Button