Carby CNS Carbs (& plugs not firing): Need info...HELP

crowvise

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grubee 2010 gt5 w/cns carb:
So I've got it all together...
Plugs won't fire under compression. One plug is proven to fire under compression on my stolen flying horse. Only used it to do a "plug chop" test on the old flying horse. Kept it as a spare.
Magneto and CDI are good (thank god) as motor actually starts when plugs is tapped to engine block acorn nut.
Gotta be something w/ the carb?
I can't find much of anything on the cns carbs. Mine only has one of the 3 hoses(the one at the bottom of the float bowl - & it seems to leak fuel:sick: should I sillycone it shut)supposed to be left idle.
Is the choke open or closed w/ remote cable pulled tight( I've tried both)?
I do like the the new built in seal for the intake.
I lost the needle pin clip & jerry rigged one by cutting a divit in a washer. It seem to work the same. Found the pin clip last night after 2 days of cleaning/searching. Have yet to reinstall it. If that doesn't work. should I try leaning out the mixture?
Any breakdowns yet on the cns? Tuning? mods( I.E.-culling the factory sealed screws and adjusting?
 
so the plug fires or doesn't fire? you have me confused, but it sounds like the plug does fire with it out of the head? you can see the spark?
is it in time? the magneto could be 180 degrees off (installed backwards).

don't silicone any of the tubes shut. for one thing the float bowl needs a vent, and if you block off the vent, the fuel will not flow right. another thign is that IF this tube is the vent, and fuel is coming out of it, the float is either set too low, or there is something in the bowl causing the needle & seat to stay open. fuel should not come out of a vent tube ever.

get yourself some starting fluid, and spray a SMALL amount in the carb, then try to start the engine right away.
if it does not fire on starting fluid, you have an ignition problem. if it fires on starting fluid, then you have a fuel delivery problem.
i'm not sure which is open and which is closed on the cns carb choke, but i think it's more of an air bleed than a choke. I would assume that up would be open and down would be closed. I think that this carb uses a brass dowl (like a rod) for the "choke" and i think if it is up the choke is on (closed), and down the choke is off (open), but i'm not sure,
I have a look alike cns carb and this is how mine works, I never hooked up the choke cable and my choke is down all the time, which must mean that it's open if it's down because my engine runs great.
 
I see what you meant about confused.
I was in a hurry to get to work from the library computer. Too many thoughts and not enough time to type even half of them or preview my post. I see a grammer issue in it as well. I would edit it but I can't see (nor remember)the edit icon on this phone.
My old cell phone kicked the internet bucket awhile back and the library was my only inlet until a bought this new cell. Work/sleep schedule pretty much kept me from getting downtown to access the old knowledge box.
Anyways, what I meant to say was that the plugs "appear" to not fire under compression. That both fire outside the engine. And that one is proven to fire under compression (though it was not on a slant head then, as it is now).
In answer to "can you see the spark? Yes, and I even got to feel it. Not fun. But it didn't "knock" me "off your bike" as someone in the engine troubleshooting sticky said it should when replying to the "redneck plug test" comment.
 
(Continued due to cell phone bit/byte capacity)
"is it on time?" : don't know, whats the poor mans way of finding out?
Should I try flipping the magneto?(God, I "flipping" hope that will work)
I sprayed some starter fluid into the air intake, replaced cover, nothing. Tried again w/o replacing cover, still nothing. i may have used too much? I did two, 1-second bursts each time. A friendly coworker let me use his cell to access this post about 5 days ago but there wasn't any time to reply or thank you for your help covering so many bases. I didn't recall the fact that you stated using a "SMALL" amount of fluid. Could the amount I used possibly have flooded it? How much is an acceptable amount?Should I apply it inside the spring loaded cylinder instead?...
thanks
I gotta get some sleep now though theres alot more poop I'm simply exausted at the moment
 
well, starting fluid will evaporate really fast so i doubt that you flooded it with that small amount.
I read somewhere that a weak magneto will give you spark, but not enough to fire the fuel.
this can be frustrating because in this case, you can pull the plug out and check for spark. the plug will spark and appear to be fine. then you put the plug back in and the engine won't fire. so since you have spark, you assume that it is a fuel problem and you end up chasing your tail.
by chance, do you have anything hooked to the white wire coming from the engine? sometimes, if a light is hooked to the white wire, it will steal enough voltage to give you the results you are describing. i know, because i had a headlight hooked to my white wire, i had spark and fuel but my engine would not run.
I unhooked the light and bang, it fired right up and has been running fine ever since.

I do not know how to test a magneto for the correct voltage so i can't help you there.
is it in time? well, the easy way to find out is to flip the magneto over and try it.
i suppose you could try to watch the piston going up & down through the sprk plug hole and try to watch the plug at the same time to see when it sparks, but i don't think that is as easy as just flipping the magneto over.
that may not be your problem either tho, but really, if you sprayed starting fluid in it, and it had spark, and it was in time it should have fired briefly. but then again if it is 180 degrees out of time, it should have backfired or caughed out of the carb if the plug fired the starting fluid. try opening the throttle 100% and spraying the fluid into the carb with the air filter and housing removed. this will let the starting fluid get directly into the cylinder. just give it a small shot, maybe less than what you used last time. if it fires don't try to run it by spraying more starting fluid into the carb because it is "dry" and there won't be any oil for the bearings. just use the starting fluid to try and get the engine to fire quickly and then shut off.

at this point i am not sure exactly what the problem is, but i am leaning towards an ignition problem.
 
Well, I'm back in a world of adquate internet connection.
I bought a netbook from verizon.
I can search and get results. I can recieve web pages instantanously or, on a rare occasion, 5-10 seconds vs. 3-10minutes (or a retry after waiting that long, again and again). And all my posts that ate up time to create are now actually going through to our site.
What I had been using was supposed to be a new 3G phone. But I have seen 3G phones and this netbook is 3G as well. same problems with all phones I've had w/ Virgin Moble.
Anyway, that is my explaination and apology for this and any other thread's lack of response. Also why I must now dabble in the art of digitized necromancy and resurrect this thread and possibly any others within "witch:shifty2:" I can recall being a part of...
Sorry, and thanks to all for your understanding and attempts to assist me.

Now, on back to this show(see, that wasn't an off topic commercial for verizion)...
My problem was the inside clutch spring needed adjusting. I found the answer a little while ago here www.motoredbikes.com/showthread.php?t=28794&page=2 in post #12 by GearNut.
I tried it out about 7 1/2 hours ago and the engine now turns on. Since it has never done this before I am happy.
I won't say it runs though because I have no torque. It turns on and only stays on while peddling. there is a change in sound when the throttle is adjusted but still no torque. I was thinking maybe an air leak (its a fake @ss grubee model CNS). But am wondering if I should try to tighten the inner adjusting sprocket some more. I already did approx 1&1/2 turns and the Gear masta said too much can break the pinion. I am also thinking about lowering the carb clip but if I recall correctly it is in the middle right now. if not it is only one notch away in either direction.
Gonna renotch it, to super rich, now but even if that works I'm wondering on any feedback regarding further adjustment of inside clutch spring adjustment sprocket. Also air leaks.
I had rtv siliconed the carb to the intake manifold a looooong time ago as per instructions at the ''other" site but 2 things (sure wish there was a "Thing 1 [TM]" & "Thing 2 [TM]" icon. Or u think Dr. Suess would become known here as Dr. Sue-Us :whistle:). One, I had to break the seal to remove carb to remove the clutch cable guide bolt to access the inner sprocket. But the silicone was only on the gap on top and the gaps in the plastic ring.
2, the rtv was permatex clear not black. I don't know that the clear is fuel compatable. Yet seeing how the engine never turned over until today I believe it never had real exposure to fuel until now, and that at about 8 different 5 second or so intervals Not that I wasn't going to replace it w/ black once I knew I could get it running. I was going to do that as a temporary use until a billet intake from Pirate came( which I haven't ordered yet because, as stated previously, the engine wasn't running at all until now.
As always, any feedback would be appreciated.
thx
 
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here's my thought....you say "it turns on only while peddling".
well, that tells me that what is actually happening is that the engine is not running (or turned on). i think what you are hearing is the pistion movig up & down in the cylinder due to your peddling efforts. If it stops as soon as you stop peddling (or the bike stops moving) then it is not running.
I still think you have an igntion or fuel problem.
i do not think your engine is running because if it was running, you would be able to stop peddling and take off with it.
you say no torque, but i think it's because the engine is not actually running....it's only turning over because of your peddling.
the change in sound when you move the throttle is because it's sucking in and blowing out more air when the throttle is open.
if the engine is turning over while you're peddling, then the clutch is doing it's job.

I think you should really be checking for a fuel problem or an ignition problem.
an engine "turning on" to me means that it's running on it's own. and engine that turns over is doing just that....turning over without running.(no igntion or fuel).
 
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:censored: God d@m^ it man! :censored:
Did not Albert Einstein say if the facts don't fit the theory, change the facts?
Work with me here.
I don't want it to be anything else:cry:.


Guess I'll go ahead and get the billet[(intake) would've had that & the billet head already if the stupid motor was working] and a new cdi now, bro.
I was hoping, and thinking, that since it now turned over, a little more adjusting might allow it to engage to an extent that it would give me torque.
Well, :poop:...
:rolleyes:
I tried to post to this thread awhile back about how the piston wasn't moving up and down with regularity awhile back and thought it made it through.
Screwdriver virgin mobile.
I am going to give it another full turn. and try that. But friday I'll order from Pirate and try first the cdi, then the billet with the old cdi, and then both new items together.
No wait, I had bought a new plug wire and cap awhile back but knew that piston issue was, if not in itself the issue, an issue to contend with. First I'll try that.
I'll let u know how it goes. Gotta find em first.
Thanks for all your feedback. Nobody else here seems to love me enough to tackle this problem:cry:
:rolleyes:
:D
 
well, if the piston was not moving up & down before, that would be a clutch problem. sounds like you got that sorted out already.
I don' think the billet intake will solve the problem and even if you do have a bad air leak at the intake gasket, the engine should still run (as long as it's getting fuel and spark).
here's the deal...when you say"the engine turns over" that to me means that it is not firing, no igntion, engine NOT running and idleing on it's own.
an engine turning over means that the piston is going up & down in the cylinder only.
if it's actually running when you are peddling but it won't idle, then you need to adjust your idle screw. if it's just making noise while peddling it's probably not running at all.
you say "no torque" but any enigne that is actually running will make some torque. if you have 0 torque, then the engine isn't running....an engine can not run without making torque.

so, does it actually run (make heat, smoke out the exhaust,)? or is the piston just going up & down without any ignition (no heat, no smoke out the exhaust)?
 
here's my thought....you say "it turns on only while peddling".
well, that tells me that what is actually happening is that the engine is not running (or turned on). i think what you are hearing is the pistion movig up & down in the cylinder due to your peddling efforts. If it stops as soon as you stop peddling (or the bike stops moving) then it is not running.
I still think you have an igntion or fuel problem.
i do not think your engine is running because if it was running, you would be able to stop peddling and take off with it.
you say no torque, but i think it's because the engine is not actually running....it's only turning over because of your peddling.
the change in sound when you move the throttle is because it's sucking in and blowing out more air when the throttle is open.
if the engine is turning over while you're peddling, then the clutch is doing it's job.

I think you should really be checking for a fuel problem or an ignition problem.
an engine "turning on" to me means that it's running on it's own. and engine that turns over is doing just that....turning over without running.(no igntion or fuel).

It was more than just the swish-pop, swish- pop(which it wasn't even doing before the clutch adjustment), of the piston going up and down. I know what that sounds like from my previous build. It was purring. But more like it did when I tested my plugs on it (which would mean ignition prob) now that I have had the time to think about it.
I found the new plug wire but still have to find the new plug boot. Hopefully that will work w/o having to buy a new cdi because I was going to buy a whole new kit anyway (from Pirate [if he had it in stock when I was ready to order] because from my dealings w/ him, and a couple others, they {meaning the Swashbuckeling Pirate brothers} are the :poop:, minus the files. They really to add a personal touch. Or at least did before they were preparing to open their retail store. And I'm sure it will be business as usual now. Or as soon as any kinks that develop from that tangental enterprise are worked out.) so if anything ever failed I have a quick replacement so as not to jeapordiize my job transportation.
Will post more in an hour or 2...
Sorry all, the reasons are mine alone. Gotta go ...
 
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