New to the board
Arm chair racerNew to the board
I just rebuilt the topend on my 79 ATC90 and now I have no spark. Set the valve timing, and points gap. When I was assembling the topend at one point the cam chain dropped into the engine and I had to fish it out, would this mess something up? Like now my flywheel T and F don't line up the way they should and that's why I don't have spark?
First Time Rider
Arm chair racerNew to the board
What do you mean they don't line up like they should?
The cam lobes should be pointed towards the crankcase, valves should bothe be loose, mark on cam sprocket lined up with notch on opening, piston at TDC and T mark on rotor line up with notch on stator. If that is all correct then it is timed in relation to valves and piston. Bet you are 180 off.
New to the board
Arm chair racerNew to the board
piston at TDC and T mark on rotor line up with notch on stator
What do you mean by this? Can you go into further depth
New to the board
Arm chair racerNew to the board
Nevermind I know what you are talking about to line up the T yes it is lined up. Ignition timing is set, valve timing is set, points gap looks good. Wiring all checked out. What else could I check?
Power User
Got the holeshot
The timing chain has nothing to do with you not having spark. If your timing chain was off and everything else was correct, you would still have spark, just not at the right time.
my feedback thread http://www.3wheelerworld.com/showthr...-hoosierlogger
TRIKEFEST 11, 12, 13, 14, 15, 16
Current rides
Taurus 650 (green)
85 250es big red
83 ALT50 (5 year old daughters)
82 ALT50
82 ALT50
84 atc 70 stroked big bore 90 STILL in progress.
71 QA50
93 TRX 300 FW
You might be strong as an ox, but without a cart you are just a big dumb animal.Originally Posted by fabiodriven
New to the board
Arm chair racerNew to the board
It doesn't seem as if any voltage is coming through the stator. I can hold the black wire and pullstart it and I don't get zapped. What would cause that?
Power User
Teaching quads a lesson
Now I'm a little worried that your troubleshooting the electrical by "feel". Do you have a manual and basic tools like a analog volt meter? I say analog because the digital ones don't seem to react fast enough to sense the quick pulse.
Trikes
1970/71 US 90 (Aquarius Blue)
1970/71 US 90 (Future Project)
1972/73 US 90 Camo Project (110 Big Bore)
1972/73 US 90 Green
1982 ATC 70
1983 ATC 70 (Ladybug)
1973 ATC 70
1965 Marketeer 3 Wheel Golf Cart with 1986 Honda 250 drivetrain
TF 2015
Other
1983 Honda Z50
Feedback http://www.3wheelerworld.com/showthr...ck-for-coopool
http://www.3wheelerworld.com/showthr...k-for-coolpool
New to the board
Arm chair racerNew to the board
I have a digital voltmeter no analog
Power User
Got the holeshot
I should rephrase my previous post, the only way a timing chain can have any effect on you not having a spark, is if you forgot to put it in. You have something else wrong in your system. There is something you forgot to hook up, or hooked up incorrectly. The timing chain will only dictate when you get your spark. Hence the name.
my feedback thread http://www.3wheelerworld.com/showthr...-hoosierlogger
TRIKEFEST 11, 12, 13, 14, 15, 16
Current rides
Taurus 650 (green)
85 250es big red
83 ALT50 (5 year old daughters)
82 ALT50
82 ALT50
84 atc 70 stroked big bore 90 STILL in progress.
71 QA50
93 TRX 300 FW
You might be strong as an ox, but without a cart you are just a big dumb animal.
New to the board
Arm chair racerNew to the board
OK i've checked my points gap and ignition timing and they look to be perfect. Is there anything else I should check? I might just put the damn thing on craigslist I feel like i've checked everything
New to the board
Arm chair racerNew to the board
OK I poked around with a multimeter and found a shorted wire and finally got it fired up and running. Almost there, but now I have one last problem. When I start it up it doesn't want to run without the choke on. I'm assuming that would be a lean condition. I checked to make sure there weren't any air leaks and I'm sure there aren't, is there anything else I could check? I might just buy an eBay carb and call it a day, I'm sick of messin with the damn thing
New to the board
Arm chair racerNew to the board
Can I use a 110 carb if I get a new intake manifold?
Power User
Teaching quads a lesson
Does it run better or the same as before the teardown? Stick with your stock carb. Clean it thoroughly and check the float height. Set your air/idle screw to factory setting too. BTW there's no guarantee the eBay carbs work any better; and it will need to be cleaned too before use.
Trikes
1970/71 US 90 (Aquarius Blue)
1970/71 US 90 (Future Project)
1972/73 US 90 Camo Project (110 Big Bore)
1972/73 US 90 Green
1982 ATC 70
1983 ATC 70 (Ladybug)
1973 ATC 70
1965 Marketeer 3 Wheel Golf Cart with 1986 Honda 250 drivetrain
TF 2015
Other
1983 Honda Z50
Feedback http://www.3wheelerworld.com/showthr...ck-for-coopool
http://www.3wheelerworld.com/showthr...k-for-coolpool
Got The Holeshot
Arm chair racerJust too addicted
I just have one thing to say there is no such thing as a 79 atc 90. in 79 they switched to the 110. so you either have a 77-78 atc 90 or a 79 atc 110
New to the board
Arm chair racerNew to the board
My mistake it is a 77. I just putted around on it today and it was running ok at first but then it started bogging out and backfiring out of the carb and exhaust. I do not have the stock intake, I am using an aftermarket eBay cone air filter. I thought I was running lean but I pulled the spark plug and it looked totally black so I'm not sure. Would backfiring be from a rich or lean condition?
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