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Spark plugs only last 2 days

5K views 23 replies 5 participants last post by  flitecontrol 
#1 · (Edited)
So i had to open a new topic as i couldn't modify the existing one, sorry about that. Anyway at first i thought only my left spark plug have lots of carbon , on brand new instated plugs , but then i realized its both sparks plugs that get the carbon real quick, i mean , i take them off to clean them and im back to riding, engine runs so smooth and so nice its hard for me to believe he rings are gone, although the engine spills white smoke only when it starts, once the engine warms up, the smoke goes away, so i wonder for the more experienced riders or mechanics out here, could it be that the carburetor its running rich or lean? Or the white smoke at start its a sign of the rings? Valve problem perhaps? what should i look for to fix this? thanks for any help and pardon my bad grammar, English its my second language.
 

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#2 ·
Wet and dry compression tests on each cylinder will identify or eliminate a number of things, including bad rings. Have you adjusted the valves recently? That may also help eliminate some possibilities. White smoke is gas, blue smoke is oil.

Compare your plugs to this chart and tell us which condition they most resemble. Spark Plugs
 
#3 · (Edited)
number 3 for sure, and ill post a picture tomorrow as well, ive been reading about "Carbon Fouled" some say carb problem ,some say, valves, so im not sure, ill just wait for advise here.
Edited to upload pics, i clean the plugs this morning, this picture was taken at nigh, one looks ok the otherone black, but on the morning they both where black. so i gues one burns faster.
 

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#4 ·
So inspecting the carb myself, i realised the Shock was on all the times, the bike does not have a shock cable but it has the little plastic cober on the carb side, i took it off and saw the shock was there, using a tool i took it off and now the carb gets way more air and runs way more faster at iddle. It moved the iddle knob to make it runs slower, but even with the knob all the way down bike seems too acelerated at iddle, i wonder if there are any ohter screws that can help slower down the rpms at iddle, i stole a pick to explain wich knob im talking about. Anyway im arun the bike like that a few days to see if that helps with the spark plugs and the white smoke too.
 

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#5 ·
There is a screw that controls the air/fuel mixture. It is part number five in this diagram. https://www.cheapcycleparts.com/oemparts/a/hon/5053e037f870021c54be031c/carburetor

It comes from the factory with a tab that limits how much it can be turned. It may be missing on yours. Tighten it to the point of lightly seated. Too much and the delicate tip will be bent/destroyed. Once lightly seated, turn it out 2 3/4 turns. With the engine fully warm, adjust it in or out no more than 1/4 of a turn at a time to get the optimum effect. If the tab is still on the screw, you will have to open up the carb to turn the screw more than about 3/4 of a complete circle.
 
#6 ·

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#10 · (Edited)
You both guys, sorry english is my second lenguage and sometimes autocorrect screws me more than it helps. Anyway yes Choke was the correct word. I do have the Choke nut and the part that goes inside, thats the part that i took out, so the carb gets lots of air now. So if i insert the metal part back again the carburetor seems to not like it too much. So Im trying to build a bobber and most of the that i see in the internet, seem to not have this cable, so question is, How can i go about that? And also i found the screw for the airflow, and mess with it ,with no good results. Thaks for the kind advice.

Edit, should i put back the cylindrical plunger, maybe with a piece of string to make it saty on top instead of the bottom?
 
#11 ·
There is a replacement for the OEM choke cable setup. It is a plunger type choke that usually requires the operator to hold the plunger in position until it can be released. Couldn't find a link, but several members have done this.
 
#13 ·
No worries, wish I had a second language.. you do very well..
Yes reinstall the cylinder,, you can not tune the carb without it seated at bottom of bore..

the plunger opens an additional airway passage that sucks (siphons) additional fuel from fuel bowl..
in this way it enriches air fuel mixture.. without the plunger and only enricher/choke nut in place, unfiltered air can be drawn in through the small opening cable passes through..
additionally excess fuel may be drawn through enricher system..

When the cylinder is seated at bottom that is enricher/choke off.. operating choke switch on handle bar, pulls on cable raising the cylinder allowing filtered air to flow siphoning extra fuel..

I have tried to assemble a pictorial of how the enricher/choke operates
 

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#14 ·
So basicly having the metal plunger at the bottom its consider it normal? having it at the top thats the choke working as normal? Now i get it and it make sense. Now in the morning i dont need to pull the choke to start the bike, bike starts just fine at 2 or 3 trys but with the tick withe smoke that smells like gas. So looks like im gonna need to find a way to fix the white smoke and find what causes my spark plugs to go black.
 
#17 ·
Thanks guys for the Choke mini plug info, now i need to focus on how to fix the white smoke. I notice that in fact my right spark plug gets darker quicker so i guess it would be rings, as if it where a carb problem, i would have to make but plugs dark even , right? what ill do for now just for a last test, ima swap the cables, just to see if is a cable problem that make the spark plug fail. Again, bike runs so smooth ,fast and nice even with my 110 kilos on it....that its dificult to believe the engine has a problem. Thanks for any advice guys.
 
#18 ·
so its been 2 full days running it without cleaning the spark plugs, but i allready notice the smoke follows the cable when i exchange it, the spark plug cable, so i might have either a bad cable or a bad ignition coil, so ima have to look at that first. Will post more after tonigh.
 
#19 ·
so after 2 days , the spark plugs are not that bad, i still get little carbon but easy to clea with just soap. So my bet it the carb needs some adjustment into the air gasoline mix, so im a be playing with it while i save some money to buy new rings, freaking mechanich wants almost 200 dlls to change the rings. Wich i think its overpriced as the only new parts im getting are the rings. I wonder if this is something i can do myself. I have changed rings in thepast on a 125 single piston engine. I had mi hiccups and trouble shoots but ended up well, but my father in law, wich helps me alot, tells me this one its more complicated as it has what we call a time chain or timing chain.
We do know a place where they can "rebore" not sure if its the correct term, the cylinders.
I live in a poor country and ima poor man, so i really need your opinions on this. Should i change this myself and save some money, or should i save some money and pay the mecanic?
By the way, im only changing rings because of the withe smoke at startup.Wich i still get.
Thanks for any help.
 
#20 ·
I would not attempt changing rings without a service manual. There are a lot of parts on the rebel engine upper and a few tricks. There is no doubt the people on here can guide you but get the manual. One of the guys on here has a site with his manuals on it. I have seen them and they are complete. He will let you download them free.
 
#22 ·
Actually this morning,with sparkplugs real clean, i adjusted the main air screww to 2 /14 turns and guess what, no white smoke, and it revs way better, gues it has to do with the carb, ima a keep an eye on it for a couple of days and post results. Thanks guys.
 
#23 ·
So a quick update, the white smoke prevails, theres nothing i can do to take it away, it only happens at start up, but that together with the daily carbon build on the spark plugs, tells me i need to take this with the mechanic, wich is not good either. Yu see, the reason i want to fix things myself is #1 save money #2 the are no real certified motorcycle mechanics, and most of them just want to make a quick buck even sometimes they dont do the job they got paid for and they still charge for it, so its hard to find a reliable mechanic out there. So ima have to see wich luck i have.
 
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