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Discussion Starter · #1 ·
Hi guys,

When I took the cover off my bike this spring, it was totally dead. Lights didn't work, engine didn't turn over, dead. Charged the battery. Still dead. Replaced the battery. Still nothing. Installed a new regulator/rec and starter solenoid from common motors and she started up after 2 kicks. However, only firing on the left side. That was three days ago. Since then I:

-Adjusted the cam chain, valves, and timing (points seemed to be in good shape)
-Cleaned the carbs, adjusted the floats, did a bench synchronization
-Tested the coils, they check out fine
-Put in new oil
-New spark plugs because I had some lying around.

Now, she wont start! :mad: Tried both e-starter and kick but nothing. The engine turns over but doesn't catch and is accompanied by a loud CLANK noise. I'm lost. Any suggestions on where to check or double check my work?

Thanks!

Laura
 

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I'm guessing the clank might be your starter clutch, the rollers in it (that grip the inner clutch hub, to transmit the starter rotation to the crankshaft) often get stuck after sitting over the winter. Once the bike is running again for any length of time, it often clears up on its own. as for your no-start... how did you check out the coils? have you actually seen the plugs fire when out of the engine? might seem like a dumb question, but did you check the kill switch? it's easy to overlook (we've all done it)
 

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1. Check for sparks. No sparks or weak sparks means you have an ignition issue (could be bad coils, bad or loose grounds, bad plug wires and/or caps, etc....)
2. Spray some starting fluid into the carbs' intakes and see if the bike starts. If so you have a fuel delivery issue.
 

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Discussion Starter · #4 · (Edited)
I used an indicator light to test the coils. Besides, they're relatively new. I believe they were replaced two years ago.
I pulled both plugs and they both have a spark, albeit I am not sure what a weak vs strong spark looks like.
By "did you check the kill switch" do you mean was it switched on "run"? yes :)
 

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Didja wiggle your floats when you had them out? The old brass ones get pin hole punctures in them real easy and fill with gas. They could be sinking and keeping gas from getting to your engine. The needle can stick too causing no gas to get out of carbs. If you're getting spark it's gotta be gas, compression, or incorrect spark timing causing the bike not to start. Are the plugs wet when you pull them out after you've attempted to start it?
 

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Just as an aside, are you trying to start it with the points cover off? The points sometimes ground to the points cover and prevent starting (or firing on one cylinder, as it may be). This is also a good chance to observe if you have sparking across the points, which is own set of problems.

Only other thing I'd say is to go back and do your cam chain tension/tappet clearance/ignition timing again, and make it perfect. The way I see it, the only things you've done between it running and not that would cause a no-start are that set of adjustments and your carb rebuild. Once you've verified that your tappet clearances and ignition timing is dead on, I'd move on to float heights/bench sync and re-do that too. While you've got the carbs out, verify that the wiring is all plugged into where it's supposed to be.
 

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Discussion Starter · #7 ·
Thanks guys.

I'll readjust the floats tomorrow, check to see if theres any fuel in 'em, and try with the points cover off. I have a feeling it's a fuel problem. The plugs were wet when I took them out, though I honestly couldn't tell if it was from oil or gas.

I adjusted the floats to a bit over 16mm (as per common motors suggestion) but I just checked my Clymer's and its saying 18.5. So, would that be it?
 

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I would go with whatever the Honda manual says.
 

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Discussion Starter · #11 ·
Sooo I readjusted the floats, checked for holes (they were good), and tried starting it with the points cover off. Same problem persists. When I use the e-start, the engine turns over but i get that clank sound, and when I try kicking it, the exhaust just sounds like its letting out little farts.

Could it still be fuel related or should I definitely go back into the cam chain/valves/points?
 

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Did you try starting fluid like I suggested? If it starts then you definitely have a fuel delivery issue.
Keep it simple and eliminate the obvious issues first.
 

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Yep. If it ran before, I’d guess it’s something that got touched. What about your tappet clearances? Are they too tight?
 

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In your description of ‘little farts’ from the pipes, this actually just reminds me of what happens when you try to start these bikes with carbs adjusted to run too lean. Assuming a bench sink, as part of the carb rebuilding process, I would think opening up the mixture screws a little bit, and even adding a quarter or half turn to the throttle stop screws may give you enough fuel to get it running. Then, once it’s warm, back those throttle screws off and trim the mixture screws a bit. I just kick it through this whole process, what with hearing about this clanking sound from the starter. Like a previous person already said, if you can get it running those rollers in the starter clutch will likely shake loose and it’ll be useful again. In my experience it really just works best to keep these things turned so that you can start them with the kick—simplify things by removing the starter motor and puting a plug in that hole (Common Motor part). If it can’t be started easily with the kick, the bike is out of tune—this is a good way of measuring where it’s at.
 

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Discussion Starter · #15 ·
Thanks guys. Sorry for being so slow to respond to these, I haven't had time to work on the bike at all.

So, starting fluid didn't help. Went back in and readjusted the cam chain, valves, points, made sure the floats were correct, and readjusted the mixture screw. Still. Not. Starting. Actually backfired pretty loud after several kicks. Its currently hooked up to a charger as the estarter became absolutely unresponsive.

At a loss. Any recommendations?
 

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Your timing is spot on and you’re doing it on the compression stroke? Backfiring sounds like bad timing to me.

EDIT: oddball idea, too; maybe check your grounding? I wonder if sitting let the strap-to-battery or strap-to-frame connection corrode. Not a bad idea to check your fuses too, with a multimeter.
 

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Discussion Starter · #17 ·
Checked the points again. Left one opens exactly when the LF hits the index mark on the compression stroke, right one opens exactly when F hits the index mark on the compression stroke. Is it possible that the compression is too low? I don't have an actual gauge, but I could buy one if that would tell me something.

Wiring should be good as I went over all of it last month and looked over it briefly this morning. Fuses are good. Battery is charged. I'm getting spark from both plugs.

The fuel lines aren't totally snug around the petcock -- they're a little wet with gas, so I'm going to look into buying smaller tubes or some sort of clamps, but would that be causing a fuel delivery problem to the carbs? Last time I took the carbs off (yesterday) some gas poured out, so I don't think that's the issue, but I'm just trying to narrow it down.

I appreciate everybody's input!
 

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Thanks guys. Sorry for being so slow to respond to these, I haven't had time to work on the bike at all.

So, starting fluid didn't help. Went back in and readjusted the cam chain, valves, points, made sure the floats were correct, and readjusted the mixture screw. Still. Not. Starting. Actually backfired pretty loud after several kicks. Its currently hooked up to a charger as the estarter became absolutely unresponsive.

At a loss. Any recommendations?
Backfires are a common symptom of having the points wires (or coils) swapped from left to right. Near the coils, swap the yellow wire from the points to the blue wire from the coil and vice versa.
 

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For your fuel lines, if they're really old or just dried out, it's easy to replace them - 4into1 has the OE 5.5mm fuel line. Otherwise, a clip like this helps: Moose Racing Wire Hose Clamp - 1/4"

On board with the crossed points idea too. Compression testing might not be a bad idea, but those readings are often not very indicative of the engine's actual ability to run, and usually I wouldn't think to look in that direction unless there was something that had happened to the engine (water in the cylinder, oil issues, overheating, etc).
 

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Discussion Starter · #20 · (Edited)
I borrowed a compression gauge from Autozone. Should the carbs be on or off for the test?

EDIT: Nevermind! I got it started by switching the coil plugs. Whooooops. :-?

However, it seems to be running much stronger on the left cylinder. Theres no backfiring or popping, but the right exhaust is weaker. Also -- I adjusted the idle screw so that it idles at around 1200 rpm, but when i open the throttle even a little the rpms jump up, even after I close it. It's always been finicky and requires adjusting after the engine warms up, but I'm not sure if thats indicative of something else, like the mixture screws? Both are adjusted at 1.5 turns out.


2nd EDIT: I just took it for a ride around the block. It feels like it isn't getting enough gas (or air? not sure..). This bike is usually very sensitive to the throttle but now it's slow to pick up. The floats are supposed to be set at 18.5mm, right?
 
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