ATC 200 timing -- close but no cigar?

[Burchoid]

I'm new here and have been obsessing over my new 84 200M. I have the full factory manual in PDF and have been going through everything possible.

Everything is good except -- the timing is off by about 5 degrees late. It looks like someone had aligned the spark with the letter F on the flywheel instead of the alignment mark to the left of F.
The motor starts are runs great, but does stumble once every few minutes. I plan on using 91 octane non-oxy and nothing else which seems like more reason to move the timing up to where it should be.

I had tried busting loose the screws for the CDI to rotate but I broke the tip off my screwdriver and I'm concerned I may strip or destroy something on the engine if I keep trying.

Do I leave it be or set the timing EXACTLY to spec?


Thanks,

Matt

[Burchoid]

I got a couple replies in the Member Commencement area, but none here...


The heart of my question is this -- will a 5 degree timing discrepancy affect idle and performance, and to what extent?

Has anyone experience timing aligned with the LETTER F instead of the MARK TO THE LEFT of F?


Thanks!

[Burchoid]

Align the dot on the cam timing sprocket and the crankshaft flywheel key way at 12 o’clock .

I got that, but what I am wondering is if its worth going through all the hassle of unsticking the screws with the risk of stripping them out only to make a ~5 degree adjustment.

My spark is currently aligned with the letter F instead of the alignment mark LIKE THIS:




The spark should be aligned with the mark, like this:




I've never worked with timing before and I am trying to determine if its worth buying some new tools to break the screws loose only to make such a small adjustment. Someone else on this board has to have run into the same issue/dilema?

[Burchoid]

Can you help me understand what I've said that makes you think this has anything to do with cam timing?

I'm talking about ignition timing. F on the flywheel stands for fire and that's all I was asking about.

The pics I posted are what I'm seeing on the flywheel vs. how I believe it should be set.

The question I was asking is if a slight variance from mfg spec is noticeable in engine performance. I don't want to mess with it if a few degrees doesn't matter.

[Burchoid]

Thank you Mr Dude!

I went and bought a cheapo impact screwdriver from Harbor Freight last night. I just got done giving it a go and I was able to free the stuck screws and rotate the pulse generator/rotor to be in perfect alignment with the proper mark on the flywheel.

It seems to run a bit more healthy, but the idle still wanders a bit... In fact I had to richen the mix to keep her lit. Is it worth exploring a chinese CDI at this point? This is what I have done so far and installed since picking up the ATC, all based on guidance from the Official 200M Honda shop manual:

NEW PLUG (properly gapped at .027 -- prior plug was gapped at like .015 and black)
NEW CARB (I did not touch the float level, but I did set the air and fuel screws for a good idle)
NEW FUEL LINES
NEW FUEL 91 octane pure gas (non oxy) with a half can of Seafoam
CAM CHAIN TENSIONER busted loose and set with slight upward pressure
VALVE CLEARANCES set per the manual at .05mm at TDC
AIR FILTER cleaned and relubed with 90 SAE marine gear oil
NEW OIL changed twice 5W40 heavy duty DELO (I like a double change within a few days on new-to-me engines to help flush)
IGNITION TIMING set precisely

Not relevant to the engine, I've also thoroughly lubed the chain with 90 SAE marine gear oil, straightened the handle bars, replaced the left brake lever, replaced fuel tank gasket, new taillight bulb and screws...


As you can see I am deep into the tune up of my 200M! I have NOT been able to run her hard yet.

Is there anything else I should replace or take a look at to ensure I have the most reliable machine possible???

[Rob Canadian]

I would like to ask what carb did you get? Aftermarket carbs from what I have heard are hit and miss on jet size that they come with installed. Is the old OEM carb total junk?

Most times you can clean up the OEM carb and buy a carb kit and you are good to go. Just my $0.02.

[Burchoid]

I seem to have a stable idle, idle to throttle, and throttle back to idle! No stalling stumbling or hesitation. It seems to all have stemmed from too rich of an idle pilot setting. The pilot screw was doing the opposite of what I had thought and I didn't realize it until reading the Jetting thread on the main forum.


I still have the original carb, but the pilot screw tip is broke off and is stuck in the hole. The floats were shot, it leaked, and all screws were corroded to heck. I emptied the bowl and I am keeping it around for parts.

This is the replacement carb that I installed: https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

Its from "Glenparts" and supposedly for an 84 200 ATC.

Everything lines up and it now runs well, but I noticed the Glenparts throttle slide is larger diameter and seems to have a shorter needle. I simply swapped everything at the throttle cable and she fired right up.