Misfire after sitting a few months-not fixed...

pete.v · Mar 20, 2015

jamesp said:
Dark.

Only god knows why things change sometimes, but they sure as hell do.

Drop you needle a notch (raise the clip one groove) and see if things improve. I am not saying this will fix it but It may give us some direction.

Sometime (quite often) you just have to go back to square one.

Turning the throttle screw out, dropping the slides to the deck and sink them bitches up one more time with the cable adjusters.
Then hold the slides down with your finger and turn the stops back in till you feel them just hit bottom of the slides.
Give them a couple turns in and keep them equal.

Turn the air screw in gently to the bottom and give each a 2 turns out or 1 1/2, as long as their the same and then start her up and start tweaking again.

jamesp · Mar 20, 2015

Tonight I reinstalled the stock 230 main jet (had a 260), fresh set of plugs, readjusted the idle screws, rechecked the timing with strobe, no improvement. I think I will just have to yank the carbs, go through them again, when I get a chance. Thanks for all your help.

Rohan · Mar 21, 2015

The main jets really only come into play above 3/4 throttle - and by the sounds of it you are not even getting up that far into the throttle.
As long as they are not blocked up, and the fuel tap(s) can feed enough fuel, and the fuel feed filters are clear.

The needle position controls much of the running below that - by the sounds of it they could be moved up or down in the range and see what happens.
Quite why they would alter just from standing is a trifle odd though, unless the jets are gummed up somehow. ?

Did you try tugging each throttle carb in turn, to see if the engine will rev up on just one carb.
Ascertaining if both cylinders are affected, or if its just one cylinder that won't rev would be quite useful to know where to go next....

john robert bould · Mar 21, 2015

Ludwig is right.
earth connectors can oxidize standing causing poor earthing, emery them and the frame.

jamesp · Mar 21, 2015

Wouldn't easy starting be an indication of good ground?

john robert bould · Mar 21, 2015

Sure would..but he aint got easy starting ..Quote "poor running and mis-fire." But if i was taking a punt on this i would be betting my money on the carbs , when modern fuel is left in carbs it becomes varnish like,
The amals have tiny .016 thou jets that are pressed into the carb,then a silly brass cover is pressed in ..inside this chamber is the .016 hole that no forced air will clear.. getting direct into the hole is not easy as the thin wire buckles up.. I have drilled out the other blank side to expose the jet,
More often than not its blocked ..careful poking with a very thin wire will show up as a pinpoint of light . the drilled hole is then plugged with a M8 x 6mm grub screw.

jamesp said:
Wouldn't easy starting be an indication of good ground?

Hobot · Mar 21, 2015

Its not uncommon to have intermittent conduction that is rpm-vibe &/or temp sensitive so can't rest till everything in ignition paths gone through. 3 yr ago Wes & I missed comnoz and many others at Texas L.O.Pines hauling ass through wet Mt. twisties besting ahead of approaching major cold storm fronts till 100 miles Wes needed a gas stop so floods caught and delayed us but got going again fine for 10 miles then his died. We tore into it finding boyah wires frayed but abke to fix and start to die quick again so back in to find a poor power terminal that allowed another 4 miles before dead again. So in light rain mid 40's painful fingers dug in again to find a loose red ground terminal which got him going for another mile, at which point day too shot so decided to turn tail but only got 15 mile till dead. Kicked our asses off, many folks stopping to 'help' but gave up on a fix so Wes called wife to get him after work ~125 mile away. We sat in rain an hour or so when I decided we'd prayed or cussed enough and it kicked off to make 40 more miles steep climbing phase up Ozark Plateau, Wes leading well beyond sight in the twisties - ugh he passes me coasting down dead to a wide spot a few miles back where we waited hrs for his wife till dark dusk. Pure wishful magic thinking I made Wes try one more time - surprise it ran and ran so we headed out and Wes made it 80 miles back home. He had to walk it up miles of muddy climb but was able to keep it idling lugging slipping to help him push it up and up and up - for hours - falling a few times but got it back up running. I also got mud slapped down to call him hours later with him just getting in ok. About a week later he found the last loose red earth contact on frame deep in but ran fine since. So part of why I say this is a real man's hobby as it tested our wisdom to ride out of state on antiques into pre-winter storms then our wits and endurance plus taking wife's put out mood.

pete.v · Mar 21, 2015

Just for the sake of readability, I thought I would inject a few returns.

hobot said:
Its not uncommon to have intermittent conduction that is rpm-vibe &/or temp sensitive so can't rest till everything in ignition paths gone through.

3 yr ago Wes & I missed comnoz and many others at Texas L.O.Pines hauling ass through wet Mt. twisties besting ahead of approaching major cold storm fronts till 100 miles Wes needed a gas stop so floods caught and delayed us but got going again fine for 10 miles then his died. We tore into it finding boyah wires frayed but abke to fix and start to die quick again so back in to find a poor power terminal that allowed another 4 miles before dead again.

So in light rain mid 40's painful fingers dug in again to find a loose red ground terminal which got him going for another mile, at which point day too shot so decided to turn tail but only got 15 mile till dead. Kicked our asses off, many folks stopping to 'help' but gave up on a fix so Wes called wife to get him after work ~125 mile away. We sat in rain an hour or so when I decided we'd prayed or cussed enough and it kicked off to make 40 more miles steep climbing phase up Ozark Plateau, Wes leading well beyond sight in the twisties - ugh he passes me coasting down dead to a wide spot a few miles back where we waited hrs for his wife till dark dusk.

Pure wishful magic thinking I made Wes try one more time - surprise it ran and ran so we headed out and Wes made it 80 miles back home. He had to walk it up miles of muddy climb but was able to keep it idling lugging slipping to help him push it up and up and up - for hours - falling a few times but got it back up running. I also got mud slapped down to call him hours later with him just getting in ok. About a week later he found the last loose red earth contact on frame deep in but ran fine since.

So part of why I say this is a real man's hobby as it tested our wisdom to ride out of state on antiques into pre-winter storms then our wits and endurance plus taking wife's put out mood.

jamesp · Mar 21, 2015

Awesome story. I plan to pull tank, carbs, drill out idle jet, all in between trying to resurrect my 65 GTO which I just got home from a bazing engine fire. Ever drive a blow torch?

Rohan · Mar 21, 2015

The idle jets don't do much of anything with running above 4500 rpm.

Sounds like you should take the dog for a walk, and stay away from things with gasoline for a while !!
Or ditch that lucky rabbits foot....

john robert bould · Mar 21, 2015

Be careful the jet is just under the alloy. its easy to drill to far and into the brass jet. put a piece of tube on the drill to prevent sudden break through.
move the drill bit in and out of the chuck to alter the depth,

jamesp said:
Awesome story. I plan to pull tank, carbs, drill out idle jet, all in between trying to resurrect my 65 GTO which I just got home from a bazing engine fire. Ever drive a blow torch?

jamesp · Mar 21, 2015

Tank is off, I have some loose wires from when I installed the Boyer, disconnected points. One is red, which was mentioned earlier as a ground. There are also other grounds which are being used. I can attach pictures, but can't see button for attachment.

gortnipper · Mar 21, 2015

Re: Misfire after sitting a few months-looking for suggestio

kerinorton said:
glad to hear you found your problem. I haven't had a problem like that but am experiencing a problem like leanness above idle so will bare this in mind for next time I look at the bike. 0.16 inch = 4mm easy???

Dereck

You don't want 4mm, Dereck. .016" is 0.4mm

kerinorton · Mar 21, 2015

figured that out. Missed a decimal place.
Coming up to the Tutukaka Rally on May 1st 2nd and 3rd. We will be visiting the Compter collection and the Packard museum.
Dereck

Biscuit · Mar 21, 2015

As long as the carbs are going to be off, before drillin' away check with WD 40 or carb clean to see if those passages are blocked. You've been at it so long now and got a good idle back that responds to the mix screws, which would not happen if pilot/idle circuit blocked by the way, that I still think it's a carburetor tuning and maybe balance issue.

jamesp · Mar 22, 2015

I would like to check all the wiring before I yank the carbs. There is quite a jumbled mess under the fuel tank. As long as there are no shorts, or bad connections, is there any devices that can go bad?

Rohan · Mar 22, 2015

Coils can certainly go wrong.
So can plug leads, plug caps, and all the electrical connections in the wiring loom.
Inc the main switch with key.

Have you tugged the throttle cables yet, to see if its one or both cylinders that won't rev and causing problems ?

jamesp · Mar 22, 2015

Rohan said:
Coils can certainly go wrong.
So can plug leads, plug caps, and all the electrical connections in the wiring loom.
Inc the main switch with key.

Have you tugged the throttle cables yet, to see if its one or both cylinders that won't rev and causing problems ?

No, haven't tugged on cables yet, tank is off, not running. Coils and HT leads are new from Trispark.

Is there a way to upload pictures here?

N0rt0nelectr@ · Mar 22, 2015

Re: Misfire after sitting a few months-looking for suggestio

Holmeslice said:
Hmmmm. I confess I read the first few lines of the symptoms and also saw the word "Boyer" in the text, and immediately thought of Boyer/weak battery syndrome and didn't read further. I didn't even see the part about the Trispark! My mistake.

In any case, it could very well be a weak battery, but to be honest I don't know if the kill switch will fire the ignition on a TriSpark as it does as a Boyer. Wouldn't hurt to try, and hopefully rule out the battery.

Why don't you run a hot wire directly from the battery to the Tri-Spark unit. That would by pass all the other connections and eliminate those as a cause of the misfire.

kernel65 · Mar 22, 2015

Re: Misfire after sitting a few months-looking for suggestio

N0rt0nelectr@ said:
Why don't you run a hot wire directly from the battery to the Tri-Spark unit. That would by pass all the other connections and eliminate those as a cause of the misfire.

+1

Misfire after sitting a few months-not fixed...

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