timing

hi,

i have a tomos targa 1992. i opened the magneto and there is suposed to be c.d.i. ignition but instead i find i have points and a condensor. this is great news cause i am pretty sure i can set the timing and clean the points for a hotter spark. ok my question is how do i get the magneto off and once i do how do i set the timing? any help will be apreciated. oh and by the way why the hell does my tomos have points and a condensor instead of the c.d.i ignition. well plz help.

-mike

Re: timing

Mike... You don't need to remove the flywheel to clean the points or set the timing.

I don't know what year Tomos switched to CDI.

Go to the part about setting the timing.

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General Moped Tune-Up Procedures

The first thing to check on a moped that won't run is to see if you have spark at the spark plug.

Pull the spark plug out and hold the metal part of the plug firmly against the cylinder head while you kick or pedal the moped rapidly with the key on (if it has one) and the run/off switch (if it has one) switched to run.... it might help to do this at night or in a dark garage to make it easier to see the spark.... it might also help if you have 2 people... 1 to pedal/kick, and 1 to hold the plug firmly against the cyl. head... you are looking for a blue spark to jump the gap on the plug.

Make sure you have a good spark plug to start with, a black or gunky or wet one will not spark.

.. If there is no spark.... clean the ignition points like it says below.... If there is spark... squirt a little bit of gas into the spark plug hole and try to start it.....if it starts and runs for 5 seconds and then dies, then clean the carburetor like it says below.

CLEANING the CARBURETOR

Clogged or dirty carburetors are the most common reason for poor performance.

The parts of the carb that are dirty or clogged are the small holes inside the carb (air and fuel passages).. not the outside.

The carburetor must be removed..... then you take off the float bowl (on the bottom).... then you remove the brass "main jet" in the middle of the carb.... hold it up to the light and look thru it.... it must be clean and clear..... if it is not clear you must poke a piece of fine wire thru it.... a wire plucked from a wire brush works good.... or some soft multistrand copper wire like from speaker wire or lampcord wire... don't use a drill bit !!.

Next you should screw the idle mixture screw in... ((( Make sure you count how many turns out it was set at !)))..... then remove it and all other screws.

Now you must clean out all passages in the carb with aerosol carb cleaner and compressed air... (like 100 psi)... with a blow nozzle... squirt the cleaner in ALL orifices one by one followed by a blast of compressed air.... while you are blowing air thru the holes feel with your fingers to feel where the air is coming out of and blow the other way too... take your time...... then reassemble all the parts (remember to turn the idle mixture screw out to its original setting... usually between 1 and 2 full turns out from all the way in) and reinstall the carb.

CLEANING the POINTS

The next most likely cause of bad running are dirty or mis-adjusted ignition points..... to clean them you need some fine grit sand paper (like 400 grit), a piece of clean paper, some scissors, and some aerosol brake cleaner or carb cleaner and some compressed air with a blow nozzle....... remove the ignition cover and look for the points in one of the holes in the flywheel.... lay the bike over on its side and sit on a milk crate or something to get comfortable... then cut some thin strips of sandpaper.... pry the points open with a small screwdriver and stick the piece of sandpaper in between the points and let them close.... then pull the sandpaper out.... do this several times to each side.... now pry the points open and blow them off with compressed air... then spray them with the cleaner.... then cut a strip of the clean paper and pry the points open again and drag the paper thru a few times (the paper should be clean and should drag through smoothly).... blow them off again with air while open.... now they should be good.

SETTING the TIMING

Correct ignition timing means the spark plug is firing at the correct moment in the engines rotation.. a little before TDC (top dead center.. when the piston is closest to the spark plug).

The spark plug fires the instant the points "break" open.

You want the points to open when the "F" mark on the flywheel lines up with the mark on the engine case.

Clean the points like it says above FIRST.

.. Then look on the outside of the flywheel for some lines and letters.. there should be a T mark next to a line... and an F mark next to a line... There should also be a mark on the engine case .. the T mark will line up with the mark on the engine case when the piston is at TDC.. you can remove the spark plug and stick a screwdriver in the hole against the piston and turn the flywheel.. when the piston pushes the screwdriver all the way out, the T mark will be lining up with the mark on the engine case.. the points will have already opened BEFORE that.. they should just START to open when the F (Fire) mark lines up with the mark on the engine case.

To check this accurately you would need to have special tools.

But you can do a crude "eyeball" check.

To do this you need to watch carefully when the points open in relation to when the F mark lines up with the mark on the engine case.. rotate the flywheel several times back and forth while watching the F mark to get a feel for when the F mark lines up.. then switch your eyes to the points and watch carefully for them to break.. if you are careful enough this will be good enough to run alright.

More accurate timing check.

For this you need a very thin piece of paper (like cigarette rolling paper..or a cigarette pack piece of cellophane)

All you do here is put the thin strip of paper between the points... and keep light tension on the paper (like as if you are gently trying to pull it out) while watching the F mark and the case mark as you slowly rotate the flywheel with your other hand.

Remember you are rotating the engine in the direction it normally travels (CCW as viewed from the left side of the bike..CW as viewed from the right)..the paper should slip out as the points start to open when the F mark lines up with the case mark.

So it's...one hand on the flywheel.. other hand on the paper...eyes on the F mark.

If the paper pulls out too late.. you will have to move the points set for a larger gap.

Too early.. move the points for a smaller gap.

GAS and OIL

Most mopeds have 2 stroke engines.... 2 strokes consume oil for lubrication.

Newer mopeds might have an auto-lube oil pump.. so that you don't have to pre-mix the gas and oil.... For older mopeds you will need to "pre-mix" the oil with the gas.

OIL

With modern 2-stroke oils you should probably pre-mix between 3 oz.(43 to 1) or 4 oz.(32 to 1) of oil per gallon of gas.

Make sure you buy 2-stroke oil.

Some people say synthetic works better... But I have found regular 2 stroke oil to be just as good as the much more expensive synthetic oil..

GAS

Mopeds are low performance engines designed to run on the lowest octane of gas you can buy (87 oct.) because they are afraid that somebody who doesn't know better will put the cheap stuff in..... and higher octane will not make it run better or faster or make more power.

But higher octane will not hurt your engine either.

GAS TREATMENT

I also like to put a little gas treatment in the gas every once in a while.. because moped carb jets are so tiny that they get clogged easily...the gas treatment helps dissolve stuff in the gas that might clog these jets.

I use one capfull of gas treatment per moped tankful (you buy the gas treatment at a gas station or Auto parts store)

Re: timing

thanks alot but all i wanted to know is how to set the timing for an "advanced" setting as to make more power. the bike runs great about 40mph(guessed) keeps up on an 40 mile an hour road meaning the cars are probably doing 45. i just wanted to clean the points and set them to the advanced mark to make some extra power. i am quit exited i dont have c.d.i. since points are easily messed with. but thanks. the problem is that i dont think the spaces are big enough to clean the points. my dad tells me that a gear puller will get the magneto off but it requires a hydralic press to get it on. any more help?

Re: timing

First let me say that I've never messed with a Tomos ignition, so I might make a mistake here.

The holes in flywheels are small.. but I've never seen one that you couldn't clean the points thru like my instructions say. I do it all the time.

Next.. You CAN"T set the timing with the flywheel off.. It has to be on.

If you have your heart set on removing the flywheel, a gear puller might work.. or a "Pitman arm puller" has worked for me.

(but I wouldn't remove it, its not necessary)

You do not need a press of any sort to reinstall one.. the flywheel nut pulls it tight..that's all.. make sure the key is seated correctly before you tighten the nut.

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Performance improvement by changing timing ????????

Don't be fooled into thinking that changing timing is a "magic bullet" for a lot more performance.

Quite often the manufacturer knows best.

You should understand that most mopeds have fixed ignition timing, which is a compromise between easy starting/low speed running and high speed running.

Which is why CDI's can be better, because they automatically advance and retard timing to suit RPM.

So if you want to "advance" it you can use the method I describe for timing to the F mark, only go a little farther and set the timing so that the points open BEFORE the F mark lines up with the case mark.. That will advance the timing. Don't go far.. just a little.

You might gain a little more on top end, but it might be a little harder to start and low speed running might not be the same.

The other thing is... is you advance the timing too much..you could melt a hole in the top of the piston while running it hard...so if you hear ANYTHING unusual after you advance it (like pinging)..SHUT IT DOWN AND LET IT COOL then ride it home gently and check things out.

If you blow it up.. don't blame anybody here.

I think you are safer by buying a pipe and leaving the timing set correctly.

Re: timing

Well I'm really not familier with Tomos mopeds at all.. but i know that with my peugeot, the timing is set when you put the flywheel on (my flywheel actually flew off one of the first times i attempted to start it). Its only a thing you have to do if you have the flywheel off for some reason. The little bump that knocks the points open is on the shaft of the flywheel. the flywheel is press fitted on (you can remove it with a pitman arm puller if you really really want to). But of course, with points you can mess with the point gap to change the timing a bit. Try experimenting with smaller and larger gauge gaps. you should be able to adjust the points without taking the flywheel off. first see where the points are with a feeler gauge, then mess with it little by little. making the gap bigger will make it spark earlier while making the gap smaller will make it spark later. Have fun, but do be careful because you CAN damage your engine if the timing is too far advanced.

Hey it's dan

Daniel Tisone /

Yo mike it's dan you know punk rocking racist smoker haha with the black targa LX "give me a blowjob marks sis" ahaha well hey whats your screen name mine is ImHoldenCaufield so IM me if you see me on i need to talk to you some time tonight later e-mail me as soon as possible or call me 703 354 7561

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