tomos wont start

i have a tomos targa lx. my friend had been riding my moped for a few weeks and now he was riding it w/o oil under the seat. it then seized up but it is now unseized. everything is fine now but it wont start. theres spark i think the carb is fine the piston seems to be ok. if u want u can email me at sk8ter3d4x14

Re: tomos wont start

Check the compression.


Live to ride, Ride to work

Re: tomos wont start

ya i think the theres compression. when i kick it back it sounds like its going to start nd it just wont turn go. it sounds regular but it wont end up starting

Re: tomos wont start

Yep, need new rings at least. Probably honed/bored out jug too. Just bag the injector and premix the gas.

Re: tomos wont start

so i should try the new rings. if that doesnt worker premix the gas. do u think the mopeds oil under the seat is mixing now? bc i dont know if the rings are bad? i have a 70cc kit so could that be a problem as well. and how would i get rid of the injecter? thanks for the help

Re: tomos wont start

Take off the left cover on the motor/tranny, and there are a few screws holding another "case" on top of that cover. The injector is just behind it, remove the screws that hold it in, pop it out, plug the fitting on the intake manifold, and you are set. You can then take off the tank and use underneath your seat for like a small golve compartment or somethin. Another thing you mentioned is how to tell if the injector is bad. You can't. they just go, and take the motor with them when they do. Its not a good idea to keep them on higher mileage peds or ones that have sat for a while. I hope this helps ya man.

Re: tomos wont start

could i just take the oil outa the tank under the seat?? nd then mix it nd put it in my tank? thanks for the help but do u think there could be another prob

Re: tomos wont start

spray a little Starter Fluid into the carb intake or spark plug hole.. try to start. If it fires up you've got a fuel delivery problem. If so, check/clean the carb and entire fuel pathway.

if it doesn't fire up either you've either got no spark or not enough compression (need about 80psi to start.. about 120psi to have a healthy engine) Check wiring and switches for no-spark .. use a new plug..

It's rare to have no compresion but since this engine was run without oil for a while, it could be. Use a compression tester. If rings are ok, check for a warped head or some other major leak above the rings.

Re: tomos wont start

i tried starting flued awile ago still nothing. it seems that there is compression. it sounds and feels normal. could it be the rings on the piston?

Re: tomos wont start

remove the plug, attach the plug boot, clamp the metal part of the plug to the engine block fins and crank it over. You should see a spark on the plug.

if you've got spark and it's no-go with Starter Fluid, compression is the last thing.. open the engine up and look.

You said everything is fine now.. theres spark.. the carb is fine... the piston seems to be ok. Who am i to argue? You've got the bike in front of you.. all i know is what you type. :)

Re: tomos wont start

ya theres spark. i just noticed when i weel the bike backwards it pumps like im going to start it. theres compresion wen i move it backwards wile i just wheel it. also wen i kick it backwards at the end it jerks forward.

Re: tomos wont start


Re: tomos wont start

what else could be the prob

Re: tomos wont start

only a few things are needed to fire an engine.

The piston must be moving up and down. When it moves upward, whatever is in the space above the piston must be compressed.

There must be some fuel and air in that compressed space.

A spark is needed to ignite that air:fuel mixture.

All these things (spark, compression, fuel) can be easily checked to see if they exist or not. If a engine won't fire, one or more of those things is missing.


This sort of problem has to be carefully approached. Sometimes shortcuts are taken that give false results.

For instance, lets say you don't feel like removing the spark plug to check for spark.. after all, it's a pretty good plug and the bike always ran fine with that plug. So, you just hook another plug to the boot and ground it to the engine and see a spark.. and assume that the plug inside the engine is also firing.. But, that could be a false assumption.

So, be systematic about it.. don't assume anything. Double check everything. If there's compression, fuel and a spark, it will fire.

Re: tomos wont start

how would i make my ped have more compression. im positive its got spark i checked that i no its getting fuel bc i even put it through the head nd it stillw ouldnt start so compression?? wat could be the prob here

Re: tomos wont start

if ur gonna premix it make sure you have the right mixture. A35s r 50:1


When they say 50:1 do they mean 50ml to one gallon?

Re: tomos wont start

I assume you do not have a compression testing gauge, so try this..

Remove the plug.

Get a small rag and stuff some of it into the spark plug hole nice and tight. Then kick the engine over like you're gonna start up.

The rag might pop out or it might not. If the rag doesn't pop out you've probably got a serious lack of compression problem.

Compression can leak past the rings or through a hole or gap somewhere above the rings... like through a crack in the head gasket or through an open decompression valve (if the engine has a decompression valve) or somewhere else above the rings. Or there could be a hole right though the piston crown.. you get the idea..

Re: tomos wont start

50:1 means 50 parts gasoline to one part of oil by volume.

50 gallons gasoline to one gallon of oil.

or 50 fluid ounces gas to one fluid ounce oil.

or 50 pints of gas to one pint of oil... it's all the same 50:1 ratio

a gallon is 128 ounces.

128 divided by 50 = 2.56.

So, 50:1 means one gallon of gas to 2.5 ounces of oil.


one liter of gasoline = 1,000 ml.

1,000 divided by 50 = 20

So, 50:1 means you'd add 20 ml to each liter of gasoline.

Re: tomos wont start

Just incase you are now adding only 50ml to each gallon of gasoline, add some more oil asap.. add about 25ml per gallon of fuel in the tank to get a 50:1 mix.

2.56 ounces of oil per gallon is not the same as 50ml of oil.. 2.56 ounces is close to 75 ml of oil..

if you're running only 50 ml per gallon you're running a very lean 75:1 mix ..

Re: tomos wont start

som1 told me if i got a new 70cc kit it would be fixed. could this be true? they said it will cause it to have more compression

Re: tomos wont start

well, yeah.. it could be true. _New parts in a brand new top end_ will have good compression.. 50cc or 70cc or 1000cc or 36cc.. because its all new stuff.

however, if the kit doesn't include a new head and the old head is warped or cracked, compression would still suffer.

Re: tomos wont start

i just noticed in between the head and the the 70 cc kit there is no gasket. i dont think there ever was even wen it was running

Re: tomos wont start

if there's no gasket the surfaces have to be very flat and smooth.. if you don't have the tools to check all this stuff, have someone look at the bike.. like a"free estimate". I got the feeling that whatever is wrong will be easily found .. but it might not be easily or cheaply fixed.

Re: tomos wont start

could the electrical be messed up. and there is compression. i checked by ur test

Re: tomos wont start

weird electrical things can happen to the spark .. even if the plug sparks when outside the engine it might not spark when it's inside. But these troubles are rare and an ignition that can spark at all is usually ok.

More likely is a plug is immediately fouling when attempting to start. So, no spark all of a sudden. This would point to a bunch of fuel puddled in the bottom of the crankcase or a leaking carburetor into the engine.. But the plug would come out wet and this kind of fouling can be detected.

Start with the basics like setting the plug gap properly..

and check ignition timing .. if something happened to the flywheel and it got turned around somehow (like a sheared woodruff key) it might not be sparking anywhere near piston-top dead center.

Re: tomos wont start

to test if there is any electrical problems you need to take out your spark plug and hoot it up to the boot. Lay the spark plug agaisnt the head and kick it over. If you see a spark, there is nothing wrong. If there isnt spark, it could be a fould plug, which means you have to buy a new one


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