Setting timing with points.

Its been over 30 years since i have messed with points. This is on my rd. I got the dial indicator out my factory timing marks are spot on. Common problem tdc is off on the alt. I have to set to 1.8mm which is the edge of the line on the rotor. The bike is not running at the moment. Just cleaned the carbs and do not want to put gas in them till after vacation in a few weeks.
I used to use a test light connect them to the points turn on the key turn the crank til the light comes on tighten the screws and good to do the other side i think. When i do this i can't move the timing plate far enough to get the lines lined up. I read a few articles on rds made a test light out of an 1156 bulb they said clip 1 side to positive side of the battery the other to the points and turn on the key. Turn it til the light comes on and your good to go. I am trying to figure out why you need to turn on the ignition. Anyhow time it this way the timing plate is just about centered. The points are gapped correctly also. I guess when points went out in the late 70s my brain tried to forget about them lol. Just trying to get the bugs worked out this winter i am gonn put the big pistons and dyna s in it then set it and forget it.

 

Guessing the ignition needs to be on to create the ground otherwise no V's flowing through. Can you clarify what you can't line up...your timing marks?

What about using a dwell meter? That's a big part of how I set the points on my '74 Toyota-need to have that dwell set right. Is it not adjustable on your rd? I can't imagine it not being.

 

The points create a ground that's how they work. Dwell meter only needed if your not good with a feeler gauge. I think it would be kind of hard to use on a 2 stroke 2 sets of points and a 2 stroke the needle would probably fall off lol. If i wanted to put gas in the carbs and start it i could use a timing light. Yes its the timing marks that have to be lined up. Stk timing is 2degrees btdc with the performance parts i have needs to be 1.8 has to be spot on on a 2stroke or else you will melt a piston first time you run it hard

 

Solid advice.

I love it. Talk about a "black art" my Norton still has the original Lucas auto-advance and points/"condensers"/coils for ignition. AND it's positive-ground; but we won't go there. (I use a timing light, and gap the points with a feeler gauge.)

There is probably some sort of advance mechanism, it may be behind everything. If so, you may need to block it in the advanced position to do static timing as being described.

 

I have an XS650 with all that stuff and the procedure for the static timing recommends that the automatic advance mechanism should be kept closed with wedges to avoid any sort of advance.

 

Here is the exact way you are supposto time it just cant figure out why the ignition needs to be on.

Internal combustion engines need to start the combustion fire before the piston reaches TDC because it takes an amount of time to get the gases burning. The spark happens before TDC, this is called BTDC. If you don’t start the gases burning BTDC a lot of the energy will be lost. Obviously making the burn happen at the right time is important in the production of power. .

Many automotive engines have a mechanism to change the ignition timing as the revolutions per minute (RPM) goes up. The faster an engine turns the ideal time of ignition varies (the faster it turns the more advance is needed). Yamaha RDs do not have an ignition advance mechanism. Some automotive engines have mechanical advancers and some have electronic advancers. Your bike has neither. The specification from Yamaha is that the ignition happens at 2.00 MM BTDC. They could have said 19 degrees of crank angle but that is harder to measure. You would need some kind of degree wheel attached to the crank to measure degrees. With a dial gauge you can measure 2.00 MM BTDC, which is a very good substitute for angular measurement. .

So how do I time the bike?????? .

If you have a dial gauge you use it to make sure the ignition marks on the rotor and stator window line up at the time you want ignition to occur. If you do not have a dial gauge, I guess you have to trust Yamaha that they manufactured the bike with some quality controls in place and the marks are at least close to correct. Before you attempt timing you need to make sure the ignition points are set correctly. Why? Because the coils need a minimum amount of time to saturate (gain full charge). The manual suggests a point gap of 0.3mm. Make sure the points are all the way open before measuring and adjusting and make sure they are clean. Wipe them when they are closed with a white business card (you know the kind that a businessman has with his name and address on it). When the points are closed, open the points with your finger and insert the card (.25mm white card stock will work) close the points and slowly remove the card without tearing. Do this until the points leave no mark on the white card stock. Timing the bike you want the points to open at exactly the same time as the timing marks come into alignment. If you have timing light this is easy to do. But in case you don’t have a timing light you can use an ohmmeter to do the same thing. Hook up the meter and watch it and the timing marks at the same time. As the marks come into alignment the needle on the meter should swing from 0 ohms to infinity ohms. Oh you don’t have an ohmmeter?????????? Try this little trick; the ignition switch needs to be turned on for this trick to work. What you do is hook up a small light bulb (12V) to the ignition points as one connection and positive terminal of the battery as the other. The points are closed sending electricity through the condensers to earth, hence the bulb doesn’t light up. When the points open the coil fires and your bulb lights up at the same time. You want your bulb to light up as the timing marks align. Simple? .

Timing…the next frontier. Since you do not have an advance mechanism on your RD you have to chose a number and live with it. 2.00 MM will be OK both top and bottom. You have to decide what is best for you. Be careful about advance. Some gasoline works better than other gasoline. Some like advanced ignition timing(93 octane and more), other gasoline does not like advanced ignition timing(87 octane)..

 

I've used an ohm-meter several times with success on my XS650.

 

My XS650 Special had Points and Condensers.

I employed the Test Light ~ Playing Card method.

The Platform could be maneuvered to Advance Spark.

 

I used an ohm meter that will work till i start it then will use a timing light to confirm.

 

Well finally got the rd running the ohm meter got it close put a timing light on it to get it exact. Have to pull the carbs and jump from a 25 pilot to a 32.5 bike has no low end. But when it hits 5k its at 9k in a blink of an eye.
I forgot really how light these bikes are. I have a bike drive on lift i can slide the back of the lift easy with the bike on it won't budge with my 400 honda on it. Full of gas oil ect 348 lbs

 

weak battery's will ruin your day on tring to set timing..

ruined a full day only to find out i had a bad battery..

i had 3 sets of points and 3 individual carbs to tune (no rack)

1975 kawasaki S1 250 :twisted:

point are allmost a lost art these days, sad really..

need tuning from time to time, but you can ALWAYS kick start and ride...

bad battery, who cares, lets ride.. electronics? what electronics?

(sort of kidding, a small "brain box" is there...) but sure doesn't need much juise.