Restoring an Old Motorcycle and Making It a Cafe Racer!

Hi everyone!

In this instructable, I'll show you how I restored and fixed a 34 years old bike I got (a 1984 Yamaha XJ 600) that was not longer working and how I turned it into something new: a shiny cafe racer :)

I'll also teach you how very useful steps when restoring a motorcycle like cleaning and synchronizing carburetors, removing rust from fuel tank, removing stripped bolts, etc.

My goal with this project was to fix this bike that had many problems, to give it the second life it deserves!

In the process, I also wanted to give the bike a racing look, by turning it into a beautiful Cafe Racer.

Want to learn more about fixing bikes? or do you want to watch a bike get resurrected ?

Here we go! :)

Step 1: The Full Timelapse of the Whole Project

What's better than a full time lapse of the project to show you everything I've done on this bike?

Here it is, it also has subtitles where I comment everything I do so make sure to activate them ;)

Step 2: The Bike: How It Was

So, first things first, I have to present you the bike, the motorcycle I wanted to restore and that was neglected for years.

It is a 1984 Yamaha XJ 600 (also known as the FJ 600 in the US), the very first year of this model, and one of the very first produced. This old lady is the very first 600cc, modern 4 cylinder Japanese bike and was advertised as a sport bike at the time.

It was for sale cheap for a very long time and no one wanted to buy it because it had many problems:

- The engine was not revving properly and could not go past 5000rpm, which is a shame for a 4 cylinder, because all the power comes near 8000 rpm

- The esthetics of esthetics of the bike needed to be taken care of

- One tire was leaking air

- Many parts were rusted and almost all the bolts were stripped

But the major problem here was the engine not revving properly.

Step 3: Make a Diagnostic and Plan the Work

So, now that we have the bike, the first thing is to make a full diagnostic and define the route we want to to go, and all the work we will do on the bike: what to fix, what to restore, what to replace, etc.

It is also a good idea at this point to budget everything to know how much the bike will cost in total.

Let's start by the main problem: the engine not revving. Most of time, if an engine start but is not revving properly, it may be either a fuel problem: fuel is not coming into the cylinder how it should, or an electrical problem: bad ignition timing, or bad spark plugs, coils etc.

In my case, I was 99% sure it was a fuel problem because just by opening the fuel tank, I could see that it was fully rusted... this is very common on these old bike. They sit for a long time with an empty tank so rust appears, then people just put new fuel in without dealing with the rust, and all that rust ends up in the carburetors, clogging everything.

So my plan was to remove the fuel tank, remove all the rust with rust remover, and apply resin inside to prevent rust from coming back, this method is VERY effective.

Then, for the carburetors, I planned to remove them, tear them apart, have them cleaned in an ultrasonic cleaner, and put them back with new seals and jets.

So with all this work, we should be able to fix the engine problems :)

But the work did not stopped there, the engine was only one of the problems, I also planned to do more work on the bikes, here is the complete list:

Engine:

- Fuel tank rebuild

- Carbs rebuild

- Replace the valve cover seal that was leaking and the valve cover bolts seals

- Install new spark plugs

- Repaint the engine and polish the fins of the cylinders

- Oil change and oil filter change

- Install a new exhaust muffler and re jet the carbs

Chassis:

- Change the the Fork Oil with new 15w heavier fork oil, making the forks stiffer which is good

- Change the old brake lines with brand new stainless steel braided brakes lines for improved braking performance, and of course bleed the brakes with new DOT3 brake fluid

- Fix the leaking tire by changing the tire valve

- Replacing old cables with brand new ones (throttle cable, etc.)

Cafe Racer modifications:

- Replacing the old rusty bars with new clip on bars

- New grips and levers

- Cutting the rear section of the frame and installing a new cafe racer seat which is a lot smaller and looks a lot better

- Reinforcing the rear section by welding a steel crossbar

- Installing side number plates for a racing look :)

- Replacing the headlight with a new LED headlight

- Replacing the old big and bulky speedometer unit with a new small speedometer

- And many more :)

Now, I won't be detailing everything step by step because you can easily see all the work done in the time lapse video with all my comments, BUT I'll give you details on some majors step that can be helpful for you if you plan on renewing a bike.
So, I'll especially teach you :

- How to remove rust from a fuel tank and how to apply resin

- How to rebuild carburetors and synchronize them

- How to remove stripped bolts

- How to change fork oil easily

- How to install new steel braided brake lines

Step 4: How to Remove Rust From a Fuel Tank and Cure It

If you buy an old bike from the 70's or 80's, there is a big chance that the fuel tank will have rust inside.

This needs to be fixed ASAP.

If you keep riding with rust in the tank, rust flakes will get in the carburetors, clogs everything, and even worse, it may also get inside the cylinders.

SO, how do you remove rust from a tank?

There are several methods for this, some use vinegar, other use small metallic balls, or dedicated products.

My tank was very very rusted so I fixed it using vinegar AND also rust remover.

Tools needed :

- Vinegar

- Rust remover

- Epoxy resin

- Towels & Hairdryer

Here is how to do it:

Step 1: Drain all the old fuel, it should be full of rust. In my case, there was even water mixed with the fuel and rust!

Step 2: Clean the tank with fresh water to remove all the major rust flakes.

Step 3: Pour vinegar inside the tank, about 5 to 7 liters, you can also add a little bit of water, then shake the tank thoroughly. Then let it sit for several days, shaking the tank everyday.

Step 4: After several days, drain the tank, you will see a ton of rust coming out because the vinegar is an acid and will dissolve rust.

At this point, most of the rust of tank is removed, but not all of it.

Step 5: Clean the tank several times with fresh water to remove as much rust residues as possible then dry it (I use a fibercloth towel I put inside the tank then a hairdryer)

Step 6: Use some rust remover: I used "Tank cure rust remover" which is very effective, all you have to do is pour it inside the tank, then let it sit for several hours by shaking it as much as possible during that time.

Step 7: Drain the tank again, now all the rust should come off, then clean the tank with fresh water again several times. Then you want to dry it the best you can!! it is very important to have the tank very dry.

Once the tank is dry and clean, we can go ahead and resin the inside of the tank.

Resin is a very effective way to prevent rust from coming back because all the inside of the tank will now be layered with epoxy resin. I used "Tank cure coating" but I think any epoxy resin will do the job.

To do this, you have to mix the 2 components of the resin together, then pour it inside the tank, close the openings with tape, then you have to slowly turn the fuel tank in every direction so the resin go everywhere. You have to do this during 20 minutes!! not more, not less, once it is done, drain the excess of resin and let your tank sit for a week.

One week later, my fuel tank was perfectly clean and cured with resin :)

Rusty fuel tank problems? FIXED ! :D

Step 5: How to Rebuild Carburetors and Synchronize Them

Since there were a lot of rust in the fuel tank, the carburetor were affected too. So they needed to be cleaned, rebuilt and tuned. Indeed, rust flakes in carbs will clog jets and any others small holes, so the engine will not get its proper fuel supply and will not run properly.

This is the step by step procedure of how I did this :)

Tools needed:

- 4 vacuum gauges (i.e a carburetor sync tool)

- Carb cleaner

- Carb rebuild kits (new seals, jets, etc.)

- Basic screwdrivers

Step 1: Remove and clean the carbs

The very first step is to remove the 4 carbs from the bike, it is fairly simple, you have to remove the fuel tank, then unscrew the collars tightening the carbs bodies to the intake manifold (the "boot" from the carbs to the cylinders) and the air box. Then you just have to unplug the throttle and choke cable, once this is done, you can just pull the whole carburetor assembly out of the bike.

Once you have the carbs out of the bike, it is time to prepare them for ultrasonic cleaning. You can also clean them by yourself but I highly recommend that you have them ultrasonic cleaning, it is pretty cheap (a local garage with a ultrasonic cleaner will charge around 30$ for one ultrasonic bath) and extremely effective.

To prepare my carbs for ultrasounds, I stared by removing the bowls and cleaning most of the rust/gum with carb cleaner, I then removed the floats, jets, needles, etc. Because the jets will be replaced anyway, and the floats can't go into the ultrasonic cleaner. Once I had removed all of this from the carbs, I brought them to my local garage for ultrasonic cleaning :)

Small tip: When removing parts from carbs, I like to draw a schematic on a piece of cardboard, then tape the parts I remove on it, that way I know exactly which small part goes where if I needed :)

Step 2: Reassemble/Rebuild the carbs

Once you get the carbs back from ultrasonic cleaning, it is time to reassemble and rebuild them.

It is pretty easy to find carbs rebuild kit on the web for almost any bike, even for 30 or 40 y/o bikes! they will most likely include new seals and gaskets, like the float chamber gaskets, and new needles, fuel filter screen, jets, etc.

A kit will cost about $10 so $40 for 4 carbs.

I got 4 carb rebuild kits for my XJ 600 so I had all theses new parts.

Rebuilding the carbs is fairly simple too, all you have to do is replace the old parts with the new ones, so I installed new jets, I went one size bigger on the main jet because I changed the exhaust, I also installed the new gaskets, fuel filter screens, needles, etc.

Once everything is reassembled, it is time to mount the carbs back onto the bike the same way we removed them :)

Step 3: Tune and synchronize the carbs

There are 2 majors things to tune when the carbs are back on the bike: the fuel mixture and the synchronization of the carbs.

Air/fuel mixture can be tuned by a simple screw located on each one of the carbs, most of the time, the factory settings will be fine. The factory setting can easily be found in the service manual of the bike. In my case, the setting was 2 and a half turn. To do this, all you have to do is screw the mixture screw all the way in, then slowy unscrew it by counting each half turn, until you reach the exact number of turns needed.

Once the fuel mixture is set, it is time to synchronize the carbs!!

Carburetor synchronization on 4 cylinders bike is very important, you want each carb to suck the exact same amount of air/fuel into each cylinder. To do this, you need 4 vacuum gauges, one for each carburetor. It is pretty easy to find some online, I got mine from aliexpress for around 60$.

In my case for example, the carbs were not synchronized at all!! so there were a major issue: when hot, the bike would idle at around 3000 rpm, and will not got back to its normal idle speed at around 1250 rpm, the problem causing this was a bad carb sync.

So, let's sync the carbs!

First of all, it is very important to do the carbs sync when the engine is hot! and by hot I mean at a normal riding temperature, not just idling for a few minutes. You have to either ride the bike for 15 minutes, or let it idle for at least 15 minutes before synchronizing the carbs.

Then, you need to remove the fuel tank and connect an auxiliary fuel supply, I used a workshop fuel bottle I connected to my carbs, but some people also use the fuel tank by laying it on something next to the bike and connecting it back to the carbs.

Then, you need to connect the 4 vacuum gauges to each carb, every bike has vacuum ports to do this. It can either be located on the intake manifold (the boot coming out of the cylinder) or on the carb body. In my case and since the XJ 600 has a vacuum activated fuel petcock, it was located on the intake manifolds.

Once the 4 gauges are connected to each vacuum port, you can start the bike and let it idle.

Then, you need to turn the synchronization screw on the carbs to achieve a perfect synchronization, that is to say the same reading on each vacuum gauge. On a 4 cylinder bike, there will be 3 sync screws: one to sync the 2 left carbs together, one to sync the 2 right carbs together, and one in the middle to sync the 2 lefts and 2 right carbs together. The exact order of synchronization will depend on your bike, but on mine, I had to sync the 2 left together first, then the 2 rights, and finally the 4 cabrs together.

When turning the sync screw, idle speed will change a lot, so you need to tune the idle speed screw to either increase or decrease idle speed to keep it at the correct idle.

Congratulations, you have now perfectly tuned your carbs!! :)

Clogged and badly tuned carbs? FIXED ! :D

Step 6: How to Remove Stripped Screws/bolts

One of the most common problem of every project!! we all know how painful it is to deal with stripped screws, even more if you did not stripped the screws yourself, I find this even more frustrating haha.

I used to struggle with stripped screws and bolt, until I found this technique.

First of all, you'll need an Impact screwdriver, and a lighter, a torch lighter is better because it won't burn your fingers and will apply heat directly to the desired zone.

The 2 bolts of my master cylinder cover were stripped so I had to remove then in order to bleed the brakes.

The first thing to do is to make a good "print" from the impact screwdriver bit onto the bolt head, to do this, remove the lower end of the impact driver, place it onto the bolt head, and give it some good whack with a hammer. It should "print" the screwdriver bit shape onto the bolt.

Then, for very stuck bolts, the best thing to do is to heat up the bolt head with a torch lighter, it'll help loosen the bolt or even remove the thread-locker glue if the bolt has some.

Once the bolt head is very warm, quick put the impact screwdriver back (make sure it is in the "unscrew" position lol) and slam it with the hammer several times.

It may look like the bolt is not moving at all first, and it may need 20 or 30 hammer before the bolt turns, but it WILL end up loosing the bolt ;)

I did this technique on about 20 stripped bolts and screw, sometimes screws that very extremely corroded with rust (in that case, adding a little bit of WD-40 will help) and it worked every time!! :D

Stripped bolts and screws?? FIXED :D

Step 7: How to Change Fork Oil

Changing fork oil is a cheap and easy way to improve the front suspension of your bike.

My XJ600 had a problem with the front work: it was extremely squishy and would dive when braking. So changing the fork oil with a higher viscosity was a great way to stiffen the forks and solve this problem. The stock visosicty was 5 or 10w on my XJ, so I used 15w heavy duty fork oil.

To change fork oil you need to:

Step 1: loosen the fork nut on the top of the fork when it is still on the bike, it will be much easier.

Step 2: remove the front wheels, brake calipers and mudguard.

Step 3: Remove the fork tubes from the bike by loosing the triple clamps bolts. You can also change the fork without removing everything from the bike, and using the drain screw on the bottom of the fork if your forks have one, but the best way is to remove the fork tubes.

Step 4: remove the fork tube cap and drain the old oil, make sure to open the drain bold on the bottom of the fork too. Then you can put your fork in a container the compress it with your hands several times to make sure the old oil drains out completely.

Step 5: pour in the new fresh oil, use the recommended quantity of oil, you can find this information in the service manual or user manual of your bike. Make sure to pour oil slowly so you don't make air bubbles.

Step 6: reinstall the forks on the bike :)

I noticed a huge difference with the 15w oil on my XJ, the front suspension a lot stiffer and ride-ability of the bike was greatly improved :)

Squishy front forks ? FIXED :D

Step 8: How to Install New Brakes Lines

A quick an effective way to improve braking on a motorcycle (aside changing brake pads and discs of course if they are worn down) is to replace the brakes lines with stainless steel braided ones.

Why change the brakes lines?

Motorcycles comes stock with rubber brake lines, under pressure, like during an important braking, the rubber tends to expand, hence reducing the pressure applied to the piston in the brake caliper.

Unlike stock rubber brake lines, steel braided brakes lines are made out of Teflon and steel, and do not expand or move under pressure, so the pressure in the braking system stays constant and more pressure is applied to the brake caliper's piston when braking, improving the stopping power :)

Moreover, old brakes lines on 80's bikes will likely need to be changed.

The front brake on my XJ 600 was a little squishy so I decided to upgrade the brake lines.

How to install steel braided brake lines:

First of all, DOT brake fluid is highly corrosive and will eat paint, so make sure to cover and protect your bike with towels or paper to avoid drips on your paint.

Step 1: Remove the old brakes lines. The first step is to drain the fluid out of the old brake lines, pretty easy to do, you "suck" the fluid out of the master cylinder reservoir using a syringe, and also from the brake caliper nipples. Then you just have to unscrew the old brake line and putting them quickly in a container so brake fluid will not go everywhere. Make sure you use towel around the banjo bolts when unscrewing the brake lines.

Step 2: Install the new brakes lines. This step is pretty easy, all you have to do is install the new brakes lines, which are plug and play if you ordered a specific kit for your bike. The very important step here is to make sure to install the crush washer correctly on the banjo bolts. There are always 2 washer on a simple banjo bolt: on before, and one after every banjo. Make sure you do not undertight or overtight the bolts, it is best to use a torque wrench for banjo bolts, and tight them to the torque specified by the manufacturer of the kit.

Step 3: Bleed the brakes. It is now time to pour new brake fluid inside the brake master cylinder reservoir and bleed the brakes. Make sure you use the correct DOT brake fluid, most bikes use DOT 4 brake fluid but older bikes sometimes uses DOT 3, my XJ600 needed DOT3, but I found some DOT 3&4 brake fluid anyway.

To accelerate the bleeding process, my tip is to open a nipple on one of the caliper then suck the air through it, using a syringe, or event your mouth haha, but make sure to use a lonnnng clear tube to avoid getting DOT4 in your mouth lol. Then, when the level on the brake reservoir starts to go down, you can start the real bleeding process, which is boring but easy: you need to pump the lever, push it in, open the brake caliper nipple then quickly close it, then release the brake lever, and repeat, and repeat, and repeat lol.

Bleeding brakes takes me about 15min that way.

After installing the new brake lines and bleeding them with new brake fluid, my braking power on my XJ was greatly improved!!

Squishy front brakes ? FIXED :D

Step 9: Enjoying My Brand New 34 Y/o Cafe Racer Bike :D

There we go!! My project is completed and the bike is awesome to ride!!

As you can see in the time lapse video, I also did many cafe racer modifications I did not detailed in the steps before, but those are mainly aesthetic modifications and do not change how the bike performs. Although it made it loose about 15kg which really improves its power to weight ratio!

My XJ 600 that was not running and that no one wanted to buy because of its terrible condition is now a sweet cafe racer that attracts the attention of everyone when riding around :D

The whole project was fairly cheap too since I did everything myself :)

I hope you guys enjoyed the restoration of the 34 years old bike that deserved a second life in my opinion :)

I love restoring bikes like that and prevent them from ending in a junkyard, they are pieces of history which show the evolution of modern motorcycle and how we got the modern superbikes.

Take care

Tom