REBUILDING FRONT BRAKE CALIPERS

A motorcycle is a compilation of many systems. Each of these systems is important and for me I hold the tires and brakes as equal in importance. The parts shown here are off a 1985 Honda VF00C with 75,000 miles of minimal maintenance. The bike, weathered and dirty, is complete, straight, and runs quite well, so the owner is justified in spending money to repair an older bike.

We put a new tire on the rear, changed and flushed the coolant, rebuilt the front forks, and lastly, rebuilt the front brakes. The first picture is the left caliper and that was the side the seal leaked worse.  

The second picture is the right caliper and is just dirty with cooked on mung.

The third picture shows both calipers disassembled.

 

A word about skill level here. Hydraulic systems like being clean. Don’t clean rubber parts with anything other than soapy water before reassembly. There are lots of parts to be careful with and those include the pistons. The pistons live a hard life. They have to move in and out under stressful conditions. Heat, water, dust, brake dust, and sometimes, high frequency vibration. Most of the time the degree of difficulty required to remove them from the caliper body is inversely proportional to the overall condition of the caliper. The dirtier and more abused it looks, including rust, the harder it will be to remove them. A C-clamp, good air supply, air gun, penetrating oil, and patience should be used with no discretion. These particular calipers had mostly dirt coating the pistons, so cleaning as much as possible before disassembly eased the process. I use an old tooth brush. Spray the entire completely disassembled caliper with a soapy solution and rinse with hot water.

If the caliper has two pistons use a C-clamp to hold one piston and blow air into the caliper body. If you’re lucky it will pop out. If it sticks, use the clamp to push the piston back in a little after spraying the penetrating oil around the piston. Back and forth…in…out…in…out and eventually both popped out.

The piston pictured had a nick towards the outer edge. I used a fine diamond file to remove the ridge and then a piece of worn 800 grit with oil to polish the piston. If the piston has corrosion pits, then I would suggest replacing the piston. I used the same piece of paper to polish the piston and remove any baked on residue.

The stripped calipers are then taken to a solvent tank and cleaned of oil and grease residue. Then I take the calipers to the glass bead cabinet and clean all the inside of the caliper including the piston bore. After this process the calipers undergo another cleaning with soapy solution and hot water. After washing, it now time for reassembly.

At this point it is extremely important to dry the caliper. Using an air gun and a contact cleaner, blow dry and all passages. Pour new brake fluid into the bores and rotate the caliper to insure the o-rings grooves are coated. Carefully install the o-rings into the bores and apply more new brake fluid to them. Using my finger, I feel the rings and feel if they are even. Confident that they properly installed, I place the brake fluid coated pistons into the bore and using my fingers only, I press the pistons into the bores. This step is a touchy feely moment. If you did everything correctly, the pistons will slide to the bottom of their bore with gentle positioning. DO NOT FORCE THE PISTONS! If they resist then remove, inspect, relube and try again.

I finish installing the brake pads and pin holders to complete the job. After cleaning the wheel and removing all traces of oil residue from the brake rotors the calipers are reinstalled and  the system bled.

REPLACING A RIM

Lacing a rim can be accomplished by anyone, providing they have a degree of patience. Follow a pattern and proceed cautiously, success can be achieved. Rims come in aluminum and steel. They can be any size from 10” to 23”. The rules are the same for all sizes. The smaller the rim, the harder the job. The shorter the spokes, the harder the job.

First lay out all the parts and count them. 36 spoke rims are the most common. The one pictured below has 60. All rims use a series of 4 spokes (2 outside and 2 inside). The inside spokes are the first to put in. The inside spokes have to be inserted first. They may be different right and left so pay attention.
The spokes shown are for a 2003 Suzuki 1400 Intruder front wheel. There are four different spokes. The top 2 spokes with the 90 degree heads are for the rotor side of the hub. The top one is an outside and the second one is the inside. The bottom 2 spokes are slightly different from each other in length. The shorter of the two is the inside.

Look at the rim. The rim holes are grouped in fours. I have shown them with the nipples slightly screwed on. Put all the insides in before the outsides.

In the above picture I have put both in and out spokes in so I can locate the other side spokes. Because I had no reference point to work from I had to do this to locate the proper position for the rotor side. There are 60 holes in the rim and 30 face one direction and 30 face the other. Once you have one side in then you can locate the other side. This causes a double step because you can’t put the inside spokes through. This is shown in the picture below.

Now you have to remove the nipples from all the outside spokes so you can thread the inside rotor side spokes into the holes in the rim.
The inside rotor side spokes are in place. Now you can insert the outside spokes. Below is what it should look like.

At this point no spokes have been tightened. The nipples have been screwed on several turns just to place all the nipples in their position. Next mark the rim, with tape, in three places 120 degrees apart. These three points will be used to align the rims radial (up & down) runout. Radial runout is done first before the lateral (side to side).

Place the wheel in a truing stand. If you don’t have a stand and can’t borrow one, then you have to be creative. You can use the axle with hose clamps to keep the hub from sliding back and forth. At each of the three points only tighten the left inside and right inside nipples. Before cranking down on them, run each nipple onto the spoke the same distance. Snug is the word. Rotate the rim and using a fixed reference point, tighten the nipples equally, a little at a time until the rim spins true on its axis. It also should be mentioned at this point to use spoke wrenches. Finding a wrench to fit the nipples is a crap shoot. Avoid using an adjustable wrench as this usually results in boogered nipples.
Continue tightening the nipples a little at a time until the side to side (lateral) runout is true. If you tighten the spokes on the right it will pull the rim to the right and vice versa. Do not tighten any spoke a lot more than any other nipple. Go slow and do a little at a time. After the rim spins true, use the spoke wrench and tap each spoke in the middle. The spoke should ring a high note. If it sounds flat and doesn’t “ping” then that spoke is loose. Use your ears and listen. It is like tuning a string instrument. The goal is have each spoke ring the same high note. They make torque wrenches to tighten spokes. I have been lacing rims for almost 50 years and have never had any issues without using one

A YEAR GONE

Well its been eleven months since I last wrote anything. That may be a good thing...I'm not sure. A lot has happened in the last eleven months. I got older, my hair got grayer, and I didn't ride all that much. The economy got worse, the government is in a mess and Lady Gaga hasn't returned my calls, tweets or skypes. I don't know what a skype is, I saw it on TV and thought it sounded cool.


Let's look at my world one subject at a time. First roadracing! The world stage saw Ben Spies capture a world championship in World Superbike, go off to Moto GP, become rookie of the year, get promoted to Rossi's vacated ride at Yamaha and Rossi sign with Ducati. That's about all exciting in the world stage. Oh yeah, Jorge Lorenzo won the first of what will be many more championships. Moto 2 became a reality pushing 250s into vintageness. Is that a word? The AMA had races, Yamaha rider Josh Hayes proved to be the man to beat and won his first Superbike championship. Congrats, Josh! Martin Cardenas won the Daytona Sportbike class after being consistent and avoiding the on track skirmishes of Danny Eslick and Josh Herrin. It pays to be consistent. There was another class for 600s, but I really didn't follow it. The AMA struggles with management, but to their credit they seem to be on the right track. The economy has hit the racing world with a hammer fist. Many riders sat out this season and many teams went belly up. All the factories downsized to support teams and some factories went home for good. I see a light at the end on the tunnel, but I'm afraid that it could be a speeding train. Motocross was a vaguely burning light with Suzuki rider rookie Ryan Dungey taking the Supercross crown after Chad Reed and James Stewart both crashed out of the series. That series was also hard hit by the economy. On the club racing scene it was the same story of depleted fields of riders.


Lets talk about the economy and politicians. The two groups of politicians are now embroiled in a power struggle of epic proportions. Each side says it's view is right and how can the other side be so wrong. I'm glad I'm an independent. I have both conservative views and liberal views. I wish we had term limits for the Washington crowd. I wish the Washington crowd had a realistic view of the middle class. I woke up this morning and discovered that while I was having all kinds of fun growing up...I suddenly got old and on Social Security. I also found out that I was 13 trillion dollars in debt and I had no way to pay the debt. We used to make stuff here in America. Now it seems that everything is made in China or some place I can't spell. Now I know why my Levis don't fit. I read yesterday that our supreme leader may not have been born in the United States. It seems there is some discrepancy about a birth certificate. How did this happen? It doesn't really matter because I don't like his socialist views anyway. I could care less where he was born.
I'm not going to rant about Healthcare or Obamacare or whatever it is called. You know the story. Those of us who work for a living don't have any say, so whatever! This is depressing! Next!


The only bright light in my world is a series for washed up race bikes and racers called Historic Moto Gran Prix. It's a loosely based series for old race bikes and old riders. It is "Gentlemans" racing. Which means that we have fun. I got to race at Road Atlanta twice this year and was that fun. We share the track with HSR, which is a race organization for historic cars. They, the really rich guys, show up with cars that I can't afford to put tires on and proceed to flog the daylights out of and then load them, the cars, back into the 18 wheelers and ship them back to California or New York or wherever. It is great fun to hear retired Le Mans winners, Formula 1 steeds, turbo Porsche's, retired Winston Cup cars and some tiny open wheel cars (I have no idea what they are) fly around the track.

After the election I had to quit watching the talking heads on TV, I am amazed that there are so many correct opinions and so many wrong opinions. One network is always right and they claim that the other networks are always wrong...wait a minute...isn't that what the politicos say? At least I have Glee, Nikita, and occasionally there is a motorcycle race.

So whats in store for new year? Kawasaki's new ZX10R was yanked off the showroom floors and new owners had to return them to dealers for a full refund. Mums the word on whats wrong. I suspect a terminal flaw of major proportions. That's a safe bet. Word has it that to get a Moto 2 ride ya need $300,000 for payment...pass. Club riders will reap the rewards of decreased fields and easier trophies. Sour grapes on my part. The Daytona 200 will return to daytime format and CCS gets the boot from Daytona in March. The CCS Race of Champions was held, again, at Homestead with only minimal rider attendance. Long way to go for a wood plaque, especially if you live in Idaho. Maybe we could find a more centrally located place...just a thought. It is held in October so weather is a factor. I have an idea...how about we start the series in August and end it a year later in August. The FTR starts its series in September and ends in May to avoid the hot weather in Florida, so why couldn't we find another time frame to work?

The politicos passed the tax bill to help us avoid a tax increase for 2 years, but they left the inheritance tax. So if a family member passes and leaves you as the inheriting heir of their house, you have sell the house to pay the taxes, up to 40% or more. That will be great in a depressed market. If Grandpa leaves you the farm you have sell it to pay the taxes. There goes your livelihood and the farm.

Doom and gloom. At least I have my family.

Longriders & Bucket Lists

I just finished reading Mark Tiger Edmonds book "Longrider". Tiger is a PhD retired English teacher at St Leo College in Florida. He is also a "longrider". For those of you that don't know what a "longrider" is, it is a person that rides more miles in a day on a motorcycle than some people ride in a year. Most good longriders use BMWs and a few use Honda Goldwings. These folks are in reality modern day cowboys, gypsies, vagabonds, wanderers, people who need to be on a quest, if for no other reason than to just be riding. They are a breed of people that are always looking for and finding the "other side" of life. I applaud them for their independence and if they had lived long ago we would call them explorers.



I have known several "longriders" in my life. They have been to all four corners of our country and many have been around the world. I want to be a "longrider", but I lack the dedication to pursue it. It takes a certain mental attitude to jump on a scooter and ride off into the sunset knowing that in four hours your ass is going to start hurting and rain storms will be in your future. I know a guy that rides the "Iron butt Rally". He tells me of riding from coast to coast in under fifty hours. "Mapquest" says that it's 2456 miles from Savannah, Georgia to San Diego, California. To complete that run you would have to average 49.12 mph. Take into consideration that you have to stop for gas, food, potty breaks and who knows what else, and I see it as a formidable task. OK I'm a wuss! I really want to go on an extended ride and now that I'm reaching my "golden years", whatever the Hell that means, it has become the lead entry on my bucket list.



I didn't know what a bucket list was until I saw the movie entitled that. After I saw the movie I thought that it wasn't just a good idea, but a necessary item to fill out, so here is my list.



1. Take a long trip on a motorcycle. Not just to a destination, but to no destination. Just load up some stuff and get on the bike, start the engine, put it into gear, let out the clutch and don't look back. You will know when it is time to go home. Take a cell phone, but leave it off until it is needed, like to call home and tell them that you are still alive or call for help if you break down.

2. Be sitting on a starting line ready to race on my sixty fifth birthday. I don't care what kind of racing, but it will either be road racing or off road racing. I'll explain why for you sometime if you ask.

3. Finish all the writing projects that I have started. Lots of stories need to be put down as a sort of legacy for my grandchildren. They will serve to explain who I was.

4. See the Grand Canyon.

5. Check in for an airplane flight wearing just a speedo and flip flops. Don't ask! It's a revolutionary thing.



That's it my very short list. I've had the opportunity to do all the other things that I wanted to do. I don't want to jump out off an airplane, unless it's sitting on the ground. I have been able to race at tracks all over the US and I've seen most of America from the boomers seat of a KC135. I've had a great marriage and wonderful friends, and I've done most everything I wanted to do when I was young. I don't want to see any place outside of these United States. There is more than enough to see here at home.



The things that I want to see are: My grandson, Conner, growing up and the wonder in his eyes as he sees what the world has to offer him. Lots of glorious sunrises and sunsets. Birds sitting on the feeder outside our kitchen windows. Great visual movies like "Avatar". That's about all I could ever want to do. Oh yea! grow older with my beautiful bride.

Well it's the day after one week till Christmas, or Saturday if you prefer. It's cold, rainy and terrible weather for a motorcycle rider. I quickly looked through the TV program and found no racing, no college games, no NFL games and whereas I don't get HD channels, I am out of luck. The news on the puter did nothing but darken my day more. Kawasaki released today the news that they were suspending all roadracing programs. Lets see if I got this straight, no Team Green, No Red Riders, the Blue Riders are in-house with Graves, Buell went belly up, and the only real team left is Yoshimura and their main man retired and went back to Aussi-land.

DMG or AMA Pro Racing (that's a hyperbole) announced purse payouts for 2010 and that won't be luring anyone to their ranks soon. I submit for your inspection.

AMERICAN SUPERBIKE
The rules for American SuperBike have had minimal change from 2009. On most event weekends, American SuperBike will have a fifty (50) mile race on Saturday and a second fifty (50) mile race on Sunday. A 2010 SuperBike License and a 2010 AMA Pro Membership is required for participation in this class. The riders earning the three (3) highest point totals on an event weekend will be paid podium bonuses as follows: 1st - $3,500.00, 2nd - $2,000.00, and 3rd - $1,000.00. Competition numbers will be assigned to licensed entrants for registered machines, as in 2009.


DAYTONA SPORTBIKE
The rules for Daytona SportBike have had minimal change from 2009. On most event weekends, Daytona SportBike will have a fifty (50) mile race on Saturday and a second fifty (50) mile race on Sunday. Riders with either a 2010 National Pro Expert License or a 2010 SuperBike License, and a 2010 AMA Pro Membership are eligible for participation in this class. The riders earning the twenty (20) highest point totals on an event weekend will be paid purse awards as follows: 1st - $5,000.00, 2nd - $3,000.00, 3rd - $2,000.00, 4th through 10th - $1,500.00 each, and 11th through 20th - $1,000.00 each. Competition numbers will be assigned to licensed entrants for registered machines, as in 2009.

SUPERSPORT
The 2010 SuperSport equipment rules are very similar to those in place for 2009; however a careful reading of the 2010 rulebook is important to avoid confusion or inadvertent violations. On most event weekends, SuperSport will have a thirty-five (35) mile race on Saturday and a second thirty-five (35) mile race on Sunday. Each SuperSport race will contain two categories of riders competing on the same track at the same time, the Top Guns and the Young Guns. The equipment rules for the two categories differ only in the required use of eligible equipment by the Young Guns riders. Riders in both categories must have a 2010 AMA Pro membership. The riders earning the ten (10) highest overall point totals on an event weekend will be paid purse awards as follows: 1st - $1,500.00, 2nd - $1,000.00, 3rd through 10th - $500.00 each.

That was copied directly from AMA Pro Racing PDF file on their website. To boil it down to it's simplist terms, you can make more money racing in the SportBike class than in the SuperBike class. The noise you just heard was the ah-ha lamp lighting. Why would anyone want to race SuperBike? A guy once asked if I knew how to make a million dollars racing? Start with two million. That was thirty years ago and adjusted for inflation today you would need five million to make a million.

So for the sake of useless tasks, if you won every SuperBike race next year, based on the current schedule a rider could earn $35,000 I'm not sure, but I don't think that will quite cover the cost of going racing. If you race the SportBike class and won every race a rider could take home $50,000. That should cover the costs, if you are a privateer and you and your buddy drive to every race in a van pulling a trailer, stay at Motel 8, eats snacks and drive thru food, don't waste your tires and the engine goes the entire season without breaking or refreshing. Oh! and by the way do not crash. Not only does crashing suck, but it affects cash flow, both in and out.

Lets boil it down a little more: Bike at cost $10,000, Bodywork 2 sets unpainted $2000, Rear shock $1500, Cartridge set front forks $2500, Spare wheels 1 front and 1 rear $1000, Braided lines $200, Stands $275, Tire warmers 2 sets $1500, Rearsets $500, Engine work (no special parts just Supersport spec stuff) $3000, Tires 2 sets $800, Spools and sliders (trinket stuff) $300, and this doesn't include all the other stuff needed to follow the circuit. If you want to be competitive today a rider will need two bikes and then everything doubles. The grand total, not including oil, gas, and all those other little things adds up to, drumroll please....$23,575 and you haven't won a single race yet. Let's see you win $35,000 minus initial outlay $23,575 give you $11,425 to buy vehicle gas, motel rooms, food, extra chain and sprockets, OH! crap I forgot entry fees, $2500 for fees and your partner has to get in so there's another $1000. Now you have $7925. Remember now we only have one bike, so if you want to have a spare bike at $23,575 you are now in the hole, after winning all the races, -$15,650. Where do I sign up? There is still a flaw in my plan, tires for each race are going to run $400 a set and as a guess I would expect a privateer to use at least four sets weekend at $1600 times ten race weekends added to our deficit comes to $31,650.

In 1991, we raced the AMA 600 Supersport series and it cost me $38,000 for the entire year. We didn't race any West coast races that year, staying to the East coast only. Nineteen years later I doubt that you could follow our schedule and not spend that amount twice over. Is professional racing dead in America? I'm not ready to pronounce it dead, but it has had a serious heart attack and rehab needs to be finished before anything good happens.

Where will racers go? I would expect most to go back to their roots, club racing. WERA and CCS still have good programs and there are other local programs that are seemingly enduring. I just received a letter from CCS announcing the reduction in purse payouts, but at least the entry fees are not going up. Based upon rider turnout at the ROC (Race of Champions) it would indicate that the economy has heavily impacted our sport as well.

Rubber Doughnuts

Love them or leave them you gotta have them. TIRES! A riders best friends are one of the most misunderstood items on most riders bikes. There are several things that I have learned over the years about tires:

1. All tires loose air.

2. They work best when properly hot.

3. They cost more than you want to spend on them.

4. If you don't trust them then get rid of them.

5. Shiny tires don't work!

6. Worn tires can cost more than your bike.

7. Used tires should be used to keep your boat from banging against the dock.

8. Bigger may not be be better.

9. It does matter where and when they are made.

10. They work great in wet weather, if you pay attention.

I could list more, but for now these ten points are the most important. So lets talk about them one at time. I know you don't want to hear this, but tires are porous. That means that air can pass through the rubber. It also means that you, the rider are required to check the pressure upon occasion. You should own a good pressure gauge, not the $1.00 special in the checkout lane at your local Dollar General, no offense Dollar General. Spend a few dollars on a good gauge. Go to an auto parts store and get one that is liquid filled, shock covered, with a flex hose that swivels. It will look cool in your tool box and your riding buddies will be impressed. You will also get accurate readings every time. Don't loan it people. Keep it close to your vest and it will reward you with a better handling bike.

Cold days and cold tires are bad for traction. This may sound trite, but it will not be so when you grab a big handful of throttle coming out of a corner. It won't matter if you are on a track or your favorite road. I have seen many experienced racers throw there prized possession down the road on the warm-up lap due to cold tires. I have also talked with many streeet riders who have brought a wrecked baby to me to fix because they did the exact same thing. Basic rule of thumb is; if the ambient air temperature is below 70 degrees then caution should be your byword. I bet there is a study somewhere that gives exact grip to temp ratios, but I could care less, I'm not an engineer. The key is to let your tires warm up before you hammer down. This is true on the street and on the track even if you use tire warmers. Coming from an age of no tire warmers and hard compound tires, it was imperative to properly use your warm up lap to warm your tires. I have seen riders take off their warmers go to the grid and before is time to take their warm up lap the tires had lost 80 degrees of temp. By the way, weaving does not warm up tires.

OK I agree...tires cost alot, especially good ones. But most of the time people either buy more tire than they need or less than they should. Simply put tires should match the bike and the riders ability. For example: Maladin will probably not run sport touring tires on his GSXR and Joe Bob should not run soft slicks on his 250 Rebel. Extreme example I realize, but the point is that if you do track days then you might want to stay away from Oriental tires of unknown origin. I am not going to specifically name brands for fear of reprisal, but if you have never seen a sponsor sticker on the side of a race bike with their name, then I would run away. Enough said about that.

Tires have Karma. Did I say that? I had "TYT" written on duct tape covering the speedo on my racebike and people would ask what that meant. "TRUST YOUR TIRES" It means that I could go race and forget about my tires. I came from a bias tire racing background, they were skinny, hard, slippery and the best of them sucked, and when radials hit the scene I thought I had died and gone to heaven. Tires got better as you rode them. It takes that little worry away and riding becomes much more pleasurable.

Two simple things her...shiny equals slippery tires. Get it? If they are new or you sprayed something on them to make them look better, they are slick when shiny. Don't spray anything on your tires ever, unless it's soapy water. I have had at least twenty people bust their ass in front of my shop seconds after I told them to be careful...new tires are slippery. Two got carted away in the meat wagon with broken body parts. Were they just not listening?

If you can see the inside, you need to stop riding. That white stuff in the middle of your tire is the the tires guts. It could be either a cord or steel bands. There is no traction left unless you can find a way to only ride on the side of the tire. Stop now! Nuff said. Cord = wreck + injury + $$$

Ditto the above paragraph. Stop coming to my shop and asking if I have any used tires for sale. If they are used, then they are done. If you want race takeoffs, I would say be very very careful about what you get. Some race tires do not react well on the street. There is a reason they are called race tires and not street tires. Many will never come up to an operating temp that makes them sticky when used on the street. If you have a race or track day background, then you know what I'm talking about. Buyer beware is the best advice here.

If your rim is 4 inches wide then don't put a 180/55 on it. The tire will roll over on itself and the handling gets weird. I don't care if your buddy did it and said it handled great. You may go one size larger in most instances and things will be fine , but any larger and all bets are off.

On your tire is more information about your tire than most people ever use. Tire size: Width (in mm), Height (% of width), Rim size (inches), Manufacturer, Country of manufacturing, Max load, Max tire press, Date of build (week & year) and some more stuff. The one that's important to sportier riders is the build date. Expressed in weeks and years it tells the reader how old the tire is, for example: 4407 = fortyfourth week of 2007. When you buy a tire online you should be aware of the build date, as older tires may not have the traction qualities of a new one. Tires, batteries and humans don't get better as they get older, except in my case.

I grew up in Florida and it rains a lot there. I have ridden more in the rain than I ever want to again. The grooves on your tires are called sipes or siping and the purpose is to disperse water. If you have a sport tire there is very little siping on the sides. Great for traction on dry roads, terrible for wet roads. The key here is to be aware of lean angle in the wet with these tires. You need to extend braking and be softer on the lever. I raced at Mid-Ohio in the rain two years in a a row. Sitting on the starting grid, I watched the rain approach towards the front straight. When the wall of rain was on the other side of the bridge that crosses the track just before turn one, the green flag fell for the GTO class. I sat there on my GTU bike and watched the entire GTO class disappear into a wall of water. I remember thinking, "This is going to be fun." Shortly thereafter our green flag fell and forty riders charged off into the waterfall. At the completion of the first lap there were riders down in every corner and most corners had more. One and a half hours of drenching rain were in my future. At the halfway my partner would get to have as much fun as I was. At the forty-five minute mark I exceeds the traction limits or my riding ability and fell coming out of the Keyhole. After a trip to the pits for a healthy dose of duct tape I was back on track and lapping almost five seconds faster. Now I knew how fast I could go in the rain and I got comfortable with it. We, my riding partner and I got fourth place in class that day and eleventh overall. You can go fast in the rain, but you need to relax and go with the flow.

Things that make ya go HUH?

Every now and then you run into a problem that defies common sense. It also seems to occur most often with the simplest of things. Recently I had a PW50 kick my butt over a no spark issue. How in the world can such a thing happen? I had a few nights of cognitive dissonance over an electrical system that didn't function correctly and there are only a switch, a coil, a pickup coil, a charge coil, a control unit, CDI unit and the spark plug.

The owner had taken it to another shop and was told it had a bad generator. $200.00 plus labor to fix. Labor was quoted at "a couple of hours". I don't know what that was, but it was probably going to cost at least $300.00 after taxes. They spent $100.00 for the bike. OK it wasn't a cream puff. It's missing the airbox, both fork tubes are bent and the rims wobble a bit. Hey! its a Christmas present for a little kid. If someone had given it to me at his age I would have treated it like a new Aprilla V four.

I first checked the "generator" more accurately an AC Magneto and it was putting out voltage and the pulse coil ohm'd out good. So much for the bad "generator" theory. Next I ohm'd the ignition coil and it checked good. Tried a new plug, still no spark! Checked all the wire connections, all good. PW50's have a unique switch on the throttle side. It has a Start, Run and Stop setting. The purpose is so little Johnny or Mary doesn't pin the throttle and wheelie off into oblivion. First it starts and then you switch it to run and off they go. The stop position is obvious. PW's also have a control unit. It's unclear what it does and the service manual from Yamaha doesn't help clear up it's function either. I know that it has five wires and they need to be checked.

Luckily, I have a good relationship with the local Yamaha dealer and they loaned me a Genuine Yamaha service manual. Armed with the manual I check the control unit. According to the service manual I should have an infinity reading on the W/R wire from positive across the other four wires. I have infinity reading on the W/R wire from negative across the other four wires. The plot thickens!

Go home for the night and read the service manual section on electrical system is my next plan of attack. After reading the section on ignition I realize that I am missing some point. I don't know what it is, but I am sure that I am missing it.

Next morning I decide to start from scratch. I follow the service manual step by step and get the same readings on every step that I had gotten before. The pulse coil checks good in both ohms and output. The charge coil has the same results. The ignition coil checks good on both primary and secondary circuits. All wire connections are good. All wires have continuity. (Thank you for only having a few wires) The handlebar switch has the right connections in all the right positions. The control unit still is basakwards. And there is no check for the CDI. "Replace unit with one of known value to evaluate." Great advice unless you don't happen to have another one.

Now here is the dilemma. I know that something is bad...but what? The control unit is backwards and there is no check for the CDI. Are both bad? Is one bad? Which one? I need a drink. I'm going home. I hope that I will awaken in the middle of the night, sit straight up in bed and go AH HA! That doesn't happen and as dawn arrives I still have no enlightening moment. CRAP!

The next morning the customer calls and asks what I found. I really wish I had a good answer, but as I try to explain the issue, I realize that she has no concept of what I am trying to explain. I finally just say, "I'm still working on it." She wants to know how much it's going to cost. "I don't know at this point." is my response.

"OH!" she says."

"Will it be ready for Christmas?" she asks.

"Yes!" I respond enthusiastically. I do hope I sounded convincing.

It's now time to make a decision. If I want to finish this creature in time for Christmas I will have to order a part and if it's the wrong part I will have order another part and ordering parts takes time. What to do? What to do? The control unit costs $120 and the CDI costs $60.

Time to go home. I need a drink!

I ended up calling a couple of my mechanic friends and talking with a friend here and they were as perplexed as I am. No help there.

End result, I order a CDI. Fed Ex delivers it, I plug it in, I say a prayer and spin the motor and all praise be to Micky Mouse the thing sparks like crazy. Problem solved and I need a drink.

The moral of the story: Service manuals can be wrong and sometimes experience is the best resource. A little luck helps also.

Seriously, after you have been doing this for as long as I have, I need to trust my gut feelings more. I need to have faith in what I know and not second guess my judgements. But, there are times that all you can do is go HUH?