[scootermcrad]

it's been riden for a little while... This happened awhile back too, but it was down for other stuff, so now I'm back to addressing it.

Here's exactly what's happening. I'll try to be as detailed as possible.

After riding the bike for about 15 to 20 minutes, I was cruising along about 60 mph, motor humming, RPM's pretty constant and in a normal range, and traveling on a flat road. I felt a huge loss of power and I immediately started to decelerate. Felt as if only the bike's valocity was keeping it running. As soon as I got over (across 3-lanes of traffic!!) it immediately stalled out. I let it sit for about 30 seconds and tried to kick it. Nothing. Gave it another 20 seconds and tried again. This time I got a pop, but didn't run. Kept trying, after about 20 more seconds of leg aerobics it started and ran fine. High-taled it home and put it in the garage, drank a beer and relaxed. I went to start it up again the next day and I got a single, solitary, pop after about 20 seconds of trying and then nothing for the duration of the trials. Never got it running again and I'm too damn frustrated to even try until I have an idea of what's going on.

Okay, with all that being said, here's what I've checked:
- plugs look fine, maybe a little burnt, but pretty new.
- plug wires have some cracks in them. Little dry looking. Aren't very old and I assembled them from replacement, new 7mm, early Ford type cloth spark wire. I anticipate changing those immediately!
- gas tank seems to be getting enough ventilation. I have a large hole in my flip cap that should let plenty of air in. Just re-assembled my tank after a re-line and the petcock was clean (as long as I didn't screw up my 6-day POR-15 tank lining job!!)
- compression seems a little low and I'm going to check the head torque for that.
- carbs are new, so I don't anticipate any float or needle problems, however I'm going to drain my bowls and inspect them for debris.
- gas may be old that I've been using for my test trials. I'm going to dump that on my pesky weeds and refill with some fresh 91

I've had this problem in the past and it's always when it gets warm. The motor is a fresh rebuild, carbs are new, the Joe Hunt mag is new... anything else I'm forgetting? Any thoughts? I'm sure this is just something stupid, just need to know what the hell it is!

Sorry for such a long ass post!!​

 

[el_butche]

it's been riden for a little while... This happened awhile back too, but it was down for other stuff, so now I'm back to addressing it.

Here's exactly what's happening. I'll try to be as detailed as possible.

After riding the bike for about 15 to 20 minutes, I was cruising along about 60 mph, motor humming, RPM's pretty constant and in a normal range, and traveling on a flat road. I felt a huge loss of power and I immediately started to decelerate. Felt as if only the bike's valocity was keeping it running. As soon as I got over (across 3-lanes of traffic!!) it immediately stalled out. I let it sit for about 30 seconds and tried to kick it. Nothing. Gave it another 20 seconds and tried again. This time I got a pop, but didn't run. Kept trying, after about 20 more seconds of leg aerobics it started and ran fine. High-taled it home and put it in the garage, drank a beer and relaxed. I went to start it up again the next day and I got a single, solitary, pop after about 20 seconds of trying and then nothing for the duration of the trials. Never got it running again and I'm too damn frustrated to even try until I have an idea of what's going on.

Okay, with all that being said, here's what I've checked:
- plugs look fine, maybe a little burnt, but pretty new.
- plug wires have some cracks in them. Little dry looking. Aren't very old and I assembled them from replacement, new 7mm, early Ford type cloth spark wire. I anticipate changing those immediately!
- gas tank seems to be getting enough ventilation. I have a large hole in my flip cap that should let plenty of air in. Just re-assembled my tank after a re-line and the petcock was clean (as long as I didn't screw up my 6-day POR-15 tank lining job!!)
- compression seems a little low and I'm going to check the head torque for that.
- carbs are new, so I don't anticipate any float or needle problems, however I'm going to drain my bowls and inspect them for debris.
- gas may be old that I've been using for my test trials. I'm going to dump that on my pesky weeds and refill with some fresh 91

I've had this problem in the past and it's always when it gets warm. The motor is a fresh rebuild, carbs are new, the Joe Hunt mag is new... anything else I'm forgetting? Any thoughts? I'm sure this is just something stupid, just need to know what the hell it is!

Sorry for such a long ass post!!​

that was part of the reason i sold my enfield indian.(which had a mag)
and i've had that problem with coils...on harleys

when stuff warmed up it would fail... when you tested it cool it tested fine.
i'd look there. i never figured out the enfield. i did the harleys.

butche

 

[gringo]

better start by verifying oil flow both to the top end and to the tank


good flow

 

[scootermcrad]

that was part of the reason i sold my enfield indian.(which had a mag)
and i've had that problem with coils...on harleys

when stuff warmed up it would fail... when you tested it cool it tested fine.
i'd look there. i never figured out the enfield. i did the harleys.

butche

Frustrating!! I've spent 2-1/2 years building this F'N bike and I haven't been able to take much more than around the neighborhood for fear that it would stall out and not start up again. Know what you mean!!

This has to be something silly though... just where to look???

 

[Creepinogie]

You never said if you had spark when it quit. But it could be a cracked coil that when it get's hot shorts out to ground. And you mentioned those plug wires. I'd change them right away. I doubt your problem is carburation, and you say your tanks venting fine, didn't mention if it seems to run lean, so I'm thinking ignition.

Those magneto coils can be pretty tempermental and not cheap to fix (about $80, last time I bought a mag coil) I'd go through the whole ignition system and even check the ignition switch for shorts. maybe hotwire it bypassing the switch to elliminate that problem, But it sounds like coil, or plug wires.

 

[scootermcrad]

better start by verifying oil flow both to the top end and to the tank

good flow

Hmmm... I had a little problem with a top end oil leak. It was real slight though. I'll try to take a picture of my oil line set-up. I basically just teed off my return line (everything is hard plumbed) and ran a 3/16" tube up to the rocker boxes. Joined the stock 3/16" rocker line to the supply line with a short rubber tube for some flexability. Works good, but didn't get enough of a nipple on the end of the tubes, so it seeps a bit from the rubber tube ends. Doesn't gush though.

I have great return to the oil tank. I check it just about everytime I go ride.

This may be a whole seperate issue, but worth mentioning since we're talking oil flow and return. I've got an occasional gusher from my crank case breather. Not the usual 6 or 7 drops on the floor type, but more like a 5" diameter puddle. I'm thinking I might have some junk in the oil pump. It's on my list to check. This wasn't alwasy occuring while having this stalling problem though. This is a new leak.

Are you thinking that maybe the top end is dry and the motor is seizing?? What are you thinking?

 

[Anthem]

My YZ use to do this to me. I would pull the plugs and test the spark to find I had spark. But it wasn't enough because when I would replace the plug it would fire on the first kick. But the plug would only last about 4 or 5 rides. The plug would come out looking a little black, but not to bad, and it still had spark. But I cleaned up the carb and found the jets to be pretty restricted.


So, what was happining to my bike is the plug would wet foul, and the spark was getting blown out by the gas .

The only diffrence in events is once my bike would bog out and die, it would not fire again untill I would replace the plug. Not like yours dying on the side of the road then fireing back up after a few minutes.

I had cleaned the carb about 2 months before the plug started to crap out on me. But since I cleaned them again the bike has run flawless.

Just my 2 cents.

 

[scootermcrad]

You never said if you had spark when it quit. But it could be a cracked coil that when it get's hot shorts out to ground. And you mentioned those plug wires. I'd change them right away. I doubt your problem is carburation, and you say your tanks venting fine, didn't mention if it seems to run lean, so I'm thinking ignition.

Those magneto coils can be pretty tempermental and not cheap to fix (about $80, last time I bought a mag coil) I'd go through the whole ignition system and even check the ignition switch for shorts. maybe hotwire it bypassing the switch to elliminate that problem, But it sounds like coil, or plug wires.

I'm PRAYING it's not the friggin' coil! If it's actually a mag problem I'm hoping for just a condenser or points. They're pretty cheap and if worse comes to worse won't kill my bank account if I have to buy a couple "trial" components. I'm going to be PISSED if that Joe Hunt is dead right out of the box!!!!

Will get on the plug wires right away. A buddy of mine (raygunriot) had a similar problem with just getting his started and it turned out to be the wires. Went CRAZY trying to get the thing started! Coils, rejetted the carbs, petcocks, timing, Boyer checking, filters, etc. etc. Came down to something simple.

 

[tbone16]

Im not sure how you have a bike wired, but I have read several get hot horror storys related to cars that were caused by the ignition relay. If you have a relay in the ciruit, you might want to pull it and resolder all the terminals.

 

[scootermcrad]

No relays. Super simple circuit using just a Podtronics and a kill switch wired to the magneto. I should say, TWO seperate circuits... one driven by the alternator (podtronics->lights, etc.) and one driven by the mag (kill switch).

Im not sure how you have a bike wired, but I have read several get hot horror storys related to cars that were caused by the ignition relay. If you have a relay in the ciruit, you might want to pull it and resolder all the terminals.

 

[tbone16]

No relays. Super simple circuit using just a Podtronics and a kill switch wired to the magneto. I should say, TWO seperate circuits... one driven by the alternator (podtronics->lights, etc.) and one driven by the mag (kill switch).

bummer, I was hoping to finally contribute.

 

[scootermcrad]

bummer, I was hoping to finally contribute.

All input is good contributing input in my book! Thanks man!

 

[noboD]

I'm thinking coil or condensor, they can both mess with you exactly like you discribe. I've also had brand new spark plugs that would fire in the day light and not fire under compression. Don't get frustrated, it's probably easy after you find it.

 

[JEB]

Take a screwdriver with you and next time it happens, open up the bowl drain and see if you have fuel. I don't think it's fuel, it sounds electrical, like a hot short, but that will tell you for sure if it's starving for fuel.

Once you know it's not fuel, start swapping out electrical stuff one piece at a time until it stops.

 

[Creepinogie]

Yeah, points and condenser would be way way cheaper. Check them first. Remember, most magnetos points gap is different than most battery ignition gaps so make sure you do the right gap. usually .015 vs. .020. You may want to run a clean folded piece of paper through the points when they are closed just to make sure they are clean. I don't know how many times this has saved my ass when I was on the road. You should get a good hot visible spark when you kick it. Take a plug out and hold it against ground and give her a kick and look. Do it when it's cold, assuming you have spark, put plug back in, start the bike, ride it around the block or playground or whatever until it quits, then try it again while it's still hot. If there's so spark, it's 90% chance it's coil or condenser.

If it quits and there is still a spark, then it's fuel. I'm not a triumph guy, but sometimes the vent to the bowl is plugged which does not allow ges to get past the needle and seat (because air in the bowl cannot escape) and you'll starve for gas. This is probably not your problem however. Also if your running a fuel filter, check it to make sure it's not plugged. Or restricted. Take the gas cap off and blow into the tank to "pressurize" it. if it starts again after doing that, it's either the cap not venting, the carb bowl not venting, or the fuel filter is too restrictive. This could also be the case if it'll start after sitting awhile after quitting mysteriously as gas will seep slowely back into the float bowl just enough to start it.

I dunno, you'll figure it out. and it may be a combination of problems... Don't worry, I've been there - and survived. You'll be smarter in the end for figuring it all out.

 

[mopar steve]

I think spark or lack of it after you change out the wires if that gets it runnin run it and see if it cuts off again if it does check for fire at the plugs and work back from there points ign.wires. kill switch ect.but do one thing at a time till it works.its most likely some thing simple and those are the ones that cause you to throw things... you will figure it out and that will make you stronger or smarter or.... something hell I dont know maybe not ...

 

[Polock Joe]

I'd start at the wires and make sure I had spark there and work back....sounds like an electrical gremlin. If I were Joe Nammath I would suspect vapor lock.

 

[Jovial Prankster]

Had a similar problem in a car I owned. Turned out to be a partially blocked outlet in the fuel tank. Car started fine, ran ok (especially on a full tank) but cut out when you'd been driving for a while. Seemed enough fuel would seep by the blockage when it was stood so it'd fire up, and driving it around would slosh the gas around in the tank and past the blockage, but when you were on the straight & level (freeway) not enough fuel could drain out of the tank and it'd cut out. Drove me mad for 2 weeks! Keep tryin' you'll find the problem.

 

[tbone16]

Had a similar problem in a car I owned. Turned out to be a partially blocked outlet in the fuel tank. Car started fine, ran ok (especially on a full tank) but cut out when you'd been driving for a while. Seemed enough fuel would seep by the blockage when it was stood so it'd fire up, and driving it around would slosh the gas around in the tank and past the blockage, but when you were on the straight & level (freeway) not enough fuel could drain out of the tank and it'd cut out. Drove me mad for 2 weeks! Keep tryin' you'll find the problem.

god I hate mystery gremlins like that.

 

[oldspeed]

Everyone has good suggestions but for what it's worth here is how I would approach it. Carry the tools you will need with you and some gloves so you don't burn your hands. First like someone said make sure the oil is returning to the tank, since you said you have a small oil leak you know the motor is pumping. Take it for a ride around the block till it dies, pull the plugs and see if you have spark, if not most likely the coil, when a condenser fails it usally breaks up under a load and does not just stop. If you have good spark pull the fuel line and see if it is flowing freely to the carbs. It either has to be spark or fuel unless the top end is too tight and the pistons are siezing. Since you are running a mag no other electrical issues will stop the bike unless your ground wire is hitting something and shorting out the mag. good luck