September 2008 16
Restoring the wheel of an old beat up motorcycle is a labor intensive job, but if done right it is comopletely worth it.
For these instructions I’m going to use some photos from a 1971 Yamaha RD350
When a bike is left outside for a long period of time it rusts, oxidizes, and generally just looks terrible. I dragged this bike from behind a shed in Eastern Mass where it had been rotting away for 10+ years. This is what the rear wheel looked like.
As you can see the whole motorcycle is weather torn, but we are only going to focus on the rear wheel in this post. The rear hub and drum is very dull and oxidized, the spokes are rusty, the tire is filthy, and the rim is covered in grunge.
First, take the wheel off (duh). I always like to start with the hubs first and work outwardly. I gave the hub a quick wipe down with a rag and this is what it looked like.
Aluminum is very easy to bring back to life, especially on large flat surfaces like this piece. Take some sand paper and get to it! Start with a 220 or so wet/dry paper, then jump to a 400, 800, 2000. It takes time but you’ll be rewarded handsomely for your efforts.
After a quick rough up with the 220 it will begin to look like this:
As you use finer and finer sand paper it’ll clean up like brand new. You can even use some aluminum polish once you’re done and rub it in with a terry clothe, but I generally just wipe it with a little oil instead to make it shine up. It’s amazing what a thin coat of oil will do for the look of your bike, it’ll also bring back faded paint a little bit over time (painted motors fade through thee years as the natural oils in the paint evaporate from the heat). . . but I digress….
Once you have the drum all cleaned up move on to the hub and spokes. For the most part I will leave the inside of the hub (between the spokes) be. The only way to clean up in there effectively is to either remove the spokes (not worth the effort) or have access to a sand blasting chamber. If you do have access to a bead blaster I would recommend using a walnut shell media rather than class or sand. Glass can work alright, but it tends to be a bit more abrasive than you need.
Anyway, use sand paper rolled up and folded to get into the tight areas. It definitely takes some work. The spokes are not aluminum so they won’t polish up, but you should be able to get most of the rust off them with the sand paper, then a real light spray with some WD-40 will make them sparkle.
The rim is chromed almost 100% of the time when it comes to vintage Japanese bikes. Some European bikes will have aluminum rims (which can be sanded), or hard anodized rims (which can only be cleaned and re-coated). For a chrome rim the best way to clean it is with a #000 steel wool. Do NOT use a steel wool that is any thicker, #000 is all you need, any stronger and you’ll scratch the chrome. Just run the steel wool back the forth in large sweeping motions across the chrome and you’ll see it wipe away all the rust, dirt, and oxidation in just a few minutes.
Once the rim is polished up turn your attention to the tire. Really this tire should have been replaced, but I didn’t have a replacement handy, so I just cleaned it up. Some simple soap in water works great the scrub it with a stiff plastic bristled brush. This will scrape all the dirt from between the lettering and tread. Take some time to get all the dirt off.
The last step is to shine everything up. Another light coat of oil works great. For the tires I generally spray on ‘Tire Magic’, a tire spray polish available at any auto parts store. Any tire polish should work just fine. Do your best not to get any oils, or polishes on the tread of the tire, else you’ll be skating all over the road.
Thats about it. With just a few free hours, a lot of elbow grease, and a couple inexpensive items from the auto store you can bring new life to an old motorcycle wheel.
The plan for my second stop was planned a long time ago. I wanted to stop at Majestic Trails in Rew, PA. I wanted to get into the dirt and do some riding as soon as possible. In the North Eastern United States finding public legal off-road riding is quite a challenge. Much of the available riding is on private land with paid admission.
When I was in college in western New York there was absolutely not legal off-roading in the area. I used to drive down to Majestic Trails from time to time to ride. I was excited to go back.
I got there, paid my $60 for a year long membership ($15 a day or $60 a year, geeze, their pricing structure sure has changed) and setup camp.
There was only one time during all the miles I put on my XL600 that it wouldn’t start. I ended up pushing it 6 miles back home through the hills. The bike had been running a bit strange for a few days, but it had never once let me down. I came out of a restuarant and it simply wouldn’t fire up, not even a puff. This was a very out of the ordinary problem for me.
Typically when a bike doesn’t start the first thing I check is spark. It is extremely rare for carburetors to work fine one minute and fail to such an extreme the next. My first thought was a spark issue. Old Honda singles are known to have stator issues over time. Unfortunately riding such a reliable bike broke my normal habits over time and I was no longer carrying a tool kit with me. So I had no way to pull the plug and check for spark, nor did I have a spare plug anyway. So I began pushing.
After an incredibly exhausting few hours of pushing the bike through the hills I got back to the garage. First thing I did was pull the plug and I noticed right away the plug wire cap felt loose. I pulled the cap off the wire, trimmed the wire back half an inch, and screwed it back in. I was sure I had found the culprit. I was wrong. I had spark the whole time.
Next I turned my attention to the carbs and immediately saw the problem. The tabs in the picture are used to adjust sychronization between the two carburetors. The tab on top had become quite bent gradually over time. Eventually it bent to the point where it got hung up on the rear shock spring. The right carburetor was stuck open preventing the fuel/air mixture in the cylinder from being adequate for the bike to start.
I pulled the carbs and did a thorough adjustment, and in 30 minutes the bike was purring better than it ever had.
It was finally time to go. Awesome.
I scrambled around the last couple days packing things up and cramming everything into the camper. I still had the water system issues to address, but I’d deal with that along the way.
As you can imagine things got pretty tight pretty quick. I was able to stuff a third motorcycle inside as well – but that didn’t last long.
Motorcycle shock linkages (aka rear suspension linkages) need to be cared for properly. This is the shock linkage out of my Honda XL600. When I got the bike I knew the rear shock linkage was a little worn, but neglected to replace it for several months.
Over time the linkage became extremely worn, to the point where the rear of the bike felt very loose while cornering and awful *clang* sounds echoed after every bump. I continued to ride the bike a little, but VERY cautiously. When I eventually did get around to replacing the linkage this is what I saw. Look closely at the bolt hole connecting the dog bone to the shock arm. It was extremely ovaled. This is very unsafe and could have been catastrophic if it broke while on the road.
Whenever you notice the shock linkage having play you should immediately fix it for your own safety. The XL600 does not use bearings in the linkage, just greased bushings, which is why they are prone to failure. Make sure you grease your linkage regularly if it has zerk fittings and inspect it from time to time. Most modern bikes now use bearings in the linkages which can be replaced for minimal cost without replacing the entire linkage.
To inspect the condition of your linkage is easy. First just look at it. Is it dirty, gunked up, and covered in grime? If so, take it out and give it a good cleaning, not only will you know for sure that it’s in good shape, but you’ll have a fun project for the afternoon and a nice shiney linkage.
To test if the bearings (or bushings) are worn or ovaled simply put the bike on the center stand with the rear wheel off of the ground. Grab the rear wheel and lift it upwards. If there is ANY play in swingarm then your linkage bearings (or busings) are worn and need to be inspected/replaced.
I get asked about Carburetor Cleaning regularly both from readers and from friends offline. So I’ve decided to write a definitive guide for cleaning carbs the RIGHT way. So put your tools down for a minute, grab a beer, and give this a read. You might just save yourself a lot of headache and sweat.
Carbs come in many shapes and sizes. Single carbs, dual carbs, racks of 3, 4 or 6, V racks, carbs with ticklers, carbs with accelerators, carbs with asynchronous designs, and carbs that operate vertically. While working on some carburetors is more difficult (due to design) than others, they all share the same basic components, and the process of cleaning those components is generally indentical.
BEFORE YOU START
Make sure that dirty carbs are actually your problem. Lots of things can make a bike run poorly or not start. Weak battery, corroded electrics, old spark plugs, bad timing, low compression, mis-adjusted valves, dirty air filter, and plugged exhausts can all cause poor running. I’ll write an article on how to diagnose poor running conditions shortly, but for now – lets just deal with the carbs.
OK, SO YOUR CARBS ARE DIRTY
Once it has been determined that the carbs are the problem it’s time to get to it. Some racks of carbs are easier to remove than others. If you’re working on a newer model bike the rubber boots from the airbox to the carbs and the manifold boots from the carbs to the motor should be relatively soft and pliable. On older bikes however this is rarely the case.
First remove the fuel tank, seat, and side covers. Depending on your model of bike other parts may need to be removed too. Â For many single cylinder bikes the carb can often be removed without removing any body work at all.
The bike below is a 1983 Yamaha XJ750 Seca with 4 inline Hitachi carburetors
You’ll want to loosen the circle clamps on all of the rubber boots. Sometimes I’ll even take them all right off (carefully, without bending them too badly) so that they aren’t in the way.
Inspect the airbox. On many bikes it is bolted in place to tabs on the frame. Remove those bolts and try to create as much space as possible for the airbox to pull backwards.
Next, put the bike on it’s centerstand and straddle it facing forward. Put your right hand on the right-most carburetor and your left hand on the left-most carburetor and get ready to sweat. Sometimes you’ll be able to pull the carbs straight backwards nice and easy, but that is pretty rare. I usually end up rotating them up then rotating them down as best I can while pulling backwards furiously. This can really take some work and time, especially if you’ve never done it before. In real extreme cases where you simple can’t get the carbs to pull backwards out of the manifold boots I have a couple tips. These tips should only be used in extremely difficult cases when you have been struggling for an hour and simple can’t get the carbs to pull backwards out of the manifold boots.
Tip 1: Ratchet Straps – This is sort of a last resort, but it has worked without fail for me when I’m pooling sweat on the garage floor and the carbs aren’t budging. Wrap a ratchet strap around one of the outer carbs and put the hooks somewhere on the rear of the frame. Then slowly ratchet the carbs right out of the boots. Be careful not to pull them too cockeye’d or you could damage the boots. Attach a second ratchet strap to the other side if necessary. (Note: you can do this in the opposite direction to force carbs back into the boots once they are clean.)
Tip 2: Full Pull! – You should do this before you do the ratchet strap method above. Sit down on your butt along one side of the bike. Wedge one of your feet up between the forks and the front fender, then put both hands on the same outermost carb and PULL PULL PULL! This might not work so well if you’re short! Ha.
Ok, So The Carbs are pulled back
Chances are the airbox boots are all crammed up now. Do your best to rotate the carbs up and out from the boots and pull them out one side of the bike. Sometimes it’s easier to pull the carbs out one side than the other, so have a look to see if there are frame elements, motor elements, or hoses that may block the carbs from coming out on one side.
Also keep note of the throttle cable(s) and choke cable (if there is one). Now may be a good time to loosen the nuts that hold them in place and disconnect them.
Struggle just a couple more minutes wriggling the carbs out the side.
Ok, You have the carbs off the bike
Make sure you brush off any loose dirt or grime, then flip the carbs over and remove the screws from the corners of the carburetor. Some carbs won’t have bolts in the corner and instead have a wire latch over top which can just be forced over.
Remove the bowls.
If the carbs are real gummed up the insides might look like this:
It’s obvious that these carbs are all clogged up. Some carbs might not look so bad, some might be a lot worse. It’s always a mystery what will be inside the bowls.
Now it’s time to remove the floats. It’s generally a good idea to drench everything in carb cleaner (available at any autoparts store). Sometimes the pins will practically fall right out, sometimes they’ll be so stubborn you won’t think they’ll ever come free. But they will! Carefully push on the pin from either side. Sometimes a nail and a gentle tap from a hammer is helpful. **BE CAREFUL**, using force to remove a stuck float pin can break off the pin tower. If they are really stuck and you can’t seem to work them free here are a couple tips.
Tip 1: Heat – Adding a little flame to the float pin towers can help. **Don’t Burn Down Your Garage!!**
Tip 2: Pliers – Using pliers to gently clamp the end of the pin and push it through has worked well for me in the past. **Don’t break the towers!!**
Once the float pin is out you can remove the floats, the float needle, and unscrew the float jet screen.
Set everything aside. Next remove the main jet, pilot jet, and idle jet (if there is one). They should come out easily with a flathead screw driver.
Set them aside.
Next flip the carburetors back over and remove the caps. Underneath the caps is a rubber diaphram with a spring. Sometimes the caps have a tendency to shoot off the top, so be very methodical when removing the screws. Other times the cap tends to stick down until you start to pry at it, then it shoots off, again, just be cautious and don’t loose any parts.
Next you’ll want to gently pull the slides up out of the carburetor body. You can gently pull on the rubber diaphrams, but be very careful not to tear them. If they don’t come up easily stick your finger into the carb intake and push the slide up with your finger. You can also gently pry it with a screw driver (gently). If it doesn’t want to budge don’t force it. Instead finish reading this article and pay attention to the boiling tips further down.
Now your carbs should be pretty well emptied out. If the throttle on the bike moved fluidly and smooth there is little reason to do much to the carb bodies themselves. However, if the throttle was real sticky or frozen there are a few things you can do to free it up. Sometimes just drenching all the throttle components on the carbs and letting it soak is enough, other times it is not. I generally try not to break racks of carbs apart. It isn’t often necessary and can be confusing to put everything back together in the right places. Also, the little rubber connector hoses and o-rings have a tendency to crack or leak if you mess with them. If you can’t work the throttle back and forth until its smooth have a look at the boiling tips further down.
Keep it Neat
Organization pays off.
Clean the Main, Idle and Pilot Jets
Hold each jet up to the light and see if you can look through it. The idle and/or pilot jets have extremely small holes so make sure you are looking through them straight. If you can see through the jet it isn’t clogged. There could be a little gunk built up around the edges so spray them down with carb cleaner and let them sit a bit.
If you can’t see through the jet it is clogged and needs to be cleaned. Always try the easiest things first. Here’s an ordered list of a few things you can do to clean the jet.
- Blow through it. – Rarely works, but hey, who knows.
- Compressed air. – Force 100 pounds into it. Works occassionally. Make sure to hold the jet tightly so it doesn’t go flying across the garage. You might put the jet back into the carb body to hold it in place for this.
- Soak it in cleaner. – When I first started cleaning carbs I thought carb cleaner would be the magic answer. It isn’t. In fact, I hardly ever use carb cleaner any more, because it simply doesn’t do a very good job of anything but removing varnish from the bowl and slide. But try this.
- Poking it through. – Collect a few different diameters of needle like objects. A wire from a steel bristle brush works well, a bristle from a broom works well, a baby pin, small sewing needle, etc. Very gently try to poke it through the jet. If you are using a metal needle use caution, brass jets can scratch and deform easily.
- Boiling! – This works better than anything. Toss the jets into a pot of boiling water and let them bounce around for a couple minutes. When you pull them out blow some compressed air through them and you’ll most likely be good to go.
Some idle jets can be real tricky and never seem like they’ll be cleaned out . . . Just keep working at it, I’ve never met a jet that couldn’t be cleaned.
Cleaning the Choke and Air Mixture Screw
Air mixture screws have a tendency to strip or break. If the carbs were real gummed up you might find that the air screws are stuck. Don’t force them, if they don’t want to come out, just leave them for now. It is fairly rare that these screws will need to be cleaned because they are above the float level. If you can get them out just wipe them down with carb cleaner and spray some through the jet.
Cleaning the Slide and Needle
These are easy to clean. Squirt them with a bit of carb cleaner, wd-40, or anything similar, then wipe them down with a rag. Once the varnish is gone they’re good to go. Sometimes they get heavy varnish on them which I will scratch off carefully with a piece of plastic. Scratching the slide and needle is a BAD thing, use caution.
Cleaning the Carb Bodies
Use the same squirt and wipe method noted above. Most of the time the other pressed jets and passages in the carburetors won’t be clogged. But if the bike has been sitting a real long time with squirrels in the airbox it is certainly possible. Us a compressor to blow some air into every passage you can see. Listen for the air coming out the other side. If no air compressor is available use a can of WD-40 with a straw attachment.
If some of the pressed jets are clogged it can be difficult to open them up. There are a few things you can do.
- Carb Dip – Most autoparts stores sell carb dip. It comes in a can similar to a paint can and is a VERY harsh cleaning agent. Soak the entire carbs in this dip. This dip can eat at rubber and plastics if they are submerged for too long, so try and remove everything you can from the carb bodies before soaking them. Once you pull them out swish the carbs around in a bucket of water to clean off the excess dip, then hose them down with WD-40 to get rid of the water.
- Boiling in Water – Not many people do this but it is by far the best way of cleaning carburetors. Dropping the carbs into a pot of boiling water will instantly free up stuck slides, throttle plates, and other frozen parts. It will also loosen the dirt and grime clogging up pressed jets and other passages. Just make sure to dry the carbs thoroughly with compressed air or the sun afterwards.
- Boiling in Lemon Juice – There is NOTHING BETTER at cleaning carbs than a giant pot of boiling lemon juice. The acidity from the lemons eats through everything; gas varnish, oil build up, dirt, grime, etc. Sometimes I won’t even bother doing anything but this – I’ll just remove the bowls, remove the caps, then drop everything into the pot and let it sit for 20 minutes (rotate them a few times). The one caveat to doing this is that you’ll want to wash the lemon juice off the carbs as soon as you pull them out. So have a bucket of water ready, or a can of WD-40 to hose them down. Also note that the acidity has a tendency to put a dull finish on the aluminum bodies of the carbs. This isn’t a problem in most cases, but if you must have everything shiny be prepared to do a little scrubbing and polishing afterwards. It may sound weird, but trust me, I just saved you LOTS of time. (Most dollar stores sell 1/2 gallon jugs of lemon juice, so buying a few gallons will only cost you $6. Plus you can put it back into the bottles afterwards and save it for next time.)
Cleaning the Bowls
This is pretty straight forward. Use any of the methods above to tranform your varnished bowls.
Most carb bowls are simple, just clean them up and they are good to go. But I picked this Hitachi’s for photos because they have a jet built into the bowl. You can see the ‘fifth’ hole along the edge of the bowl, that is actually a thin passage that extends to the bottom of the bowl. This is for the idle jet and is extremely important. If these passages are clogged, the bike won’t stay running, period. Use the same poke, soak, and boiling methods outlined elsewhere in this article. Not all bowls have these passages, only some, if your’s don’t – good for you!
Once Everything is Clean
Now that everything is clean it’s time to put it all back together. Take your time and make sure you put everything back where it came from. WD-40 is your friend. When screwing in the jets don’t over do it, they only need to be seated and snug, do NOT use any force putting the carbs back together.
If the bowl gaskets got goobered up you can put a little RVT on them. So long as the float needles are still in good condition leaky gaskets shouldn’t be an issue. However, prudent carb tinkerers may want to order replacements if necessary.
Once the carbs are back together stuff them back into the bike!
- Rebuild Kits – This guide did not mention rebuild kits until now. Rebuild kits (consisting of new gaskets, jets, needles, etc) can be purchased for nearly any bike, both old and new. 95% of the time these are NOT needed. I have rebuilt enough carbs to block off main street, and only once have I used new parts. ONCE!
- Carburetor Adjustment – Carburetor adjustment, setup, jetting, and synchronizing is a whole encyclopedia waiting to happen. Those topics are not covered in this article, but I will address them in future articles.
- Carburetor Polishing – External carb asthetics will be important to some, and not to others. Cleaning is all I am covering here, this will be addressed in the future.
- Work Space – Make sure you have lots of space to keep organized. I also like to work on a wooden surface because it absorbs the spilled gas and cleaners rather than pooling.
That’s it! You’re Done!
I’ll continue to write a couple more related articles about diagnosing carburetion issues as well as the proper way to adjust, jet, and tune your carbs.