Project well under way atc 70 85 i think

[crazzzzzyphil]

Hi can anyone give me a hand i have got an atc 70 85 i think.I t had bin sitting in the back yard for about 6 years and was my girlfriends ex's lol. I have totaly rebilt it. Instald a ignishon coil as it did not have one and rebilt the stater coil as all the wirers were not in the right place (it had had some cowboy at it).

Got it started affter about 4 kicks and was running well until this week. It has started not to fire at all the spark is good but when i take the plug out it is black and wet. thort it was the carb but striped that and cleaned it but still no joy. plus installed filters on the petrol lines. Could my oil 2 petrol mix be to rich? If so how do i control this mixing rate? Should i just be putting oil in the side of the gear box or should i be mixing it in the tank as well?
Can any one help cuz i am totaly baffeled with this.
All and any help well resevied

Sorry about spelling not to good at it lol

[FlyingW]

WHere are the pics Phil???????

[crazzzzzyphil]

i can't grt them onto the site from my phone. sorry m8. any way you got any ideas on this new problem?

[thefox]

Kicks? The stock 70 motor is pull start…. But the ct 70 and other Honda motors that are very similar are kick start and fit.

Assuming someone didn’t hack a motor in there and is vastly different then the stock atc motor or one of the similar dirt bike motors is is a 4 stroke so the gas and oil don’t mix. There should be a dip stick on the right side of the engine, make sure you have oil up to the top line on the dip stick.

[crazzzzzyphil]

It looks like a 70 but with out the pullstrart just a kick start. It fits into the frame perfect. I have checked the oil and it is up to level and clean.

[Gdkarma]

Here's the pictures. I don't see reason to believe this is a 2 stroke, and thus you don't need to be mixing oil with your gas. It also says 49cc on the cylinder, so now you can start narrowing down what motor you have in there!

[crazzzzzyphil]

thank you for resizing my pics for me gdkarma.
Any ideas on the starting problem?

[225]

Sorry, I don't have any information to help your issues.

[FlyingW]

Phil,

First off, this is a CT series motor. The ATC 70 came with a pull start. Not too mucg difference in the motors except for the kick starter and the carb setup. I think we are confused!! You aren't running premix in this are you (gas mixed with oil)? It looks like it needs the corrosion removed and a fresh coat of paint applied. This is to protect it more than anything otherwise, its just going to continue to rot.

The richness of the motor under power is controlled by the main jet and the nedle clip position. The lower the clip the richer it will run 1/2 throttle and above. The other factor that effects the richness of the mixture is the main jet. Stock for an ATC70 motor is a #58 which is stamped on the jet.

The other thing to be aware of is these motors came with points which are mounted under the the flywheel located on the left side of the motor. You don't need anythig special to adjust the points but given the condition of yours, it may be time for fresh points. To replace the points, you'll need a flywheel remover tool. There is no other way to remove the flywheel except with the removal tool

If you don't have a manual, go to this link and download it for free.

http://www.drivehq.com/file/ShowFolder.aspx?catID=0&subCatID=0&sort=&isInc=&isGallery=true&share=true&shareID=233462&parentID=636956&parentPath=\\dammit\manuals\

The manual is more like a service suppliment but I believe it has what you need to adjust the points. You can also go here to get the info;

http://www.intheredgraphix.com/hosted/Honda_ATC.pdf

Another good site with hours of good reading is Glamis dunes.com.

http://www.glamisdunes.com/invision/index.php?showforum=50

You'll need to register with a user name a password to view pictures in the posts but it's well worth it.

Good luck with your 70. Let us know if we can do anything to help.

[crazzzzzyphil]

Thanks m8 have alredy changed the points and rebilt the stater back up to wot it is suposed to be insted of the cow boy job that was done on it.
I have a good blue spark when i kick it but the spark plug keeps getting sooty and wet.
Any ideas?
The paint job is next on te list after it is running propaly plus all the rust is only serface rust so it an't to bad.

[FlyingW]

So, are you pre-mixing the fuel?

[crazzzzzyphil]

not pre-mixing the fuel.

[FlyingW]

Ok Phil, had to be clear about that. At this point, I'd say rebuild the carb if you can identify which one it is. Now, since the motor is a 50CC motor what carb is installed on it? That's the question. Look for the motor number stamped on the case and post it. We should be able to identify the motor. More than likely, the carb needs to be rebuilt but we need to identify it first. Look for any markings on the carb around the bowl rim.

[thefox]

Looks like a Honda Z50 motor, Honda made the Z50 mini-trail or at least that's what they called it hear in the US. Check the carb. to make sure the person that swapped out the motor also swapped the carb. A carburetor that is jetted for the 70cc motor will make the 50cc motor run real rich.

[crazzzzzyphil]

Just so i have the right bit in my hand the carb is the bit that the petrol/gas go's into? lol if it is there is a number stamped on it. The number is 38Aotct the last "T" looks more like a cristian cross and the "O" looks more like a squre than a O. There is somthing stamped in the cilander head just left of the 49cm3 (looking strate at it) L(big space)Hm-F5.

These are the only numbers that i can find on the bike engine or the chasie.
Hope that these can help?

[crazzzzzyphil]

I have had a look at the crab and the only number on it is 38AOTCT inprinted on the the top and not on the bowl.
The jet has j 50 stamped into it so i gess that means it is a 50cc jet?
The engine has L(big space)Hm-F5 to the left of the 49cm just under the reseve gas line. There is no other numbers that i can find on the engine or frame.
Hope this can help?

[crazzzzzyphil]

sorry didn't think that the last one posted lol

[FlyingW]

Phil, Look on the left side of the motor directly behind and below the shifter shaft coming out of the motor. Is there a number stamped on the case?

[FlyingW]

Looks like a Honda Z50 motor, Honda made the Z50 mini-trail or at least that's what they called it hear in the US. Check the carb. to make sure the person that swapped out the motor also swapped the carb. A carburetor that is jetted for the 70cc motor will make the 50cc motor run real rich.I'm thinking the Fox is right, It looks like a Z50 motor. Still the question is, what carb does it have on it? Z50 or ATC70.

[marcus]

it is a z50 motor. i just went out and looked at mine. it even says 49cm doesnt it?

[Gdkarma]

if it is indeed a Z50 motor, you might not be out much to find a carb for that motor.....................in the states, there's a handful of them on Ebay for pretty cheap:thumbsup:

[crazzzzzyphil]

now she wont even kick over she was running fine monday just getting soot on the spark plug but now she wont even spert of come back to life again need help!!!!!!!!!!!!!!!!!!!!!
wot couold it be. i'v changed the spark plug and am getting good spark. i'v reset the timing is there anything els that might hinder it starting???

[marcus]

carb could be flooded. but is it kicking over?

[crazzzzzyphil]

yep it kicks over and the conproshion is good. but now she wont even spark propaly. I havant done out to the bike it jujst stoped working alltogether now am really stump.