85 - 250es starts and runs great, no start when hot

[tri again]

This is a kickstart only trike for the time being.
Starts 1 or 2 kicks, will idle smoothly forever and run
forever, working, funning, slow, fast, runs like a dream.

Again, runs and idles great when warm/hot say an hour of running.

Simply doesn't want to start when hot/warm.

I know I should fix the e start but they should ALL start almost instantly.

Maybe I'll kill sw it near the compressor and blow off components
one at a time...but why would it idle and run great hot?
It's not really like something fails when it gets hot.

stumped, thanks

[barnett468]

Hi Tri Again;


Sorry to hear you have probs. You seem to know quite a bit about engines.

Initially, it sounds like weak spark and/or a slightly rich pilot condition to me.

Below is my usual list of annoying questions, lol.

How much choke do you use to start it when bike is cold?

How much throttle?

How cold is the air where you are trying to start it?

Is this a new prob?

Does it do it whether it’s hot or cold outside?

When the eng is warm, have you tried to start it with the choke partially or fully on?

What is the minimum amount of time it needs to sit before it starts again?

Is the carb orig or Chinese etc.?



Here’s just a few things to try if you want:

Install a new plug the proper heat range.

Look at the spark with eng both cold and hot. If the intensity changes noticeably, you have an electrical prob that is contributing to the hot start prob but may not be the only cause.

If spark is blue while kicking it over when hot, most the electrical tests are unnecessary and you likely have a fuel prob imo.

With eng cold and hot, remove plug, lay it on the eng, push bike and see if plug spark increases in any way.

If the spark increases, it means that you might have enough spark to fire the bike at idle but you cannot generate enough spark to fire it while kicking it because the kicking rpm is too low.

If the spark is weaker when hot, you can “chryo” cool the coil and cdi by spraying computer duster on it. It might work better than your air compressor air. If it does not come out cold enough with the can in the upright position just tilt the can and spray. The more the can gets to the upside down position the colder the air coming out will be.

Please do not turn the parts into a snowball even though freezing them will not likely hurt them. It takes a minute or two for the outside coldness to penetrate to the electronics inside.

Look at the plug when it does not restart, if it passes the electrical tests above and is wet, it is likely too rich imo.

Do the gas level test with the clear plastic hose. Tell us what it is. If it is more than around 1/8” above the bottom of the main carb body I would lower it to just a hair below the carb body.

If the gas level is good and the plug is wet, I would check the pilot screw setting. If it is less than 1/2 turn out from full in, I would install a smaller pilot and try it without changing the pilot screw setting. I might also try lowering the needle 1 position.

If it is more than 1/2 turn out, I would turn it in 1/2 turn and try it, then another 1/2 turn in and try it etc.

[tri again]

Wish I knew how to reply line by line but I was able to print.
Tomorrow will be the day to try your suggestions.

It behaves like the other 5 - 250's we have and I must admit, I am SPOILED
at the way they start, idle and run. Almost as pretty as 5 part Eagles harmony.

Supposed to be sunny and not freezing and a few kids practice racing quads tomorrow
so a perfect day for me to dig into it.
I just know I get tunnel vision when working on my own stuff so a fresh, outside perspective
is greatly appreciated.
I had one with a slow battery that wouldn't fire but with a perfect kick on compression, it would fire instantly. Has a new battery now.

Great list to have printed, for sure.

Thanks again

[barnett468]

Wish I knew how to reply line by line but I was able to print.

It’s easy to reply line by line, and the info would be nice to know [at least for me], but not necessary yet imo because I’m confident you understand what I’m trying to get at and you will easily get it fixed.

Just hit reply with quote.

Hit go advanced so you have a big screen to type on.

Erase the [barnett468 =24553] at the beginning of the post. This removes the quote feature/box, you really don't need it. You can put the members question in "parenthesis" if you want but no need to, we can figure it out.

Reply beneath each line/question etc. like I am doing here.

Erase what you don't want/need.

Put an extra space or two between the last reply and the next question.



Tomorrow will be the day to try your suggestions.

Ok cool let is know what happens.



It behaves like the other 5 - 250's we have and I must admit, I am SPOILED
at the way they start, idle and run.

Well of it behaved like the other 5 it would start when its hot just like they did. Sorry couldn’t help myself.



Almost as pretty as 5 part Eagles harmony.

Eagles rule, their base player lives in laguna calif and plays regularly in a local bar there when they are not on tour.



I just know I get tunnel vision when working on my own stuff so a fresh, outside perspective
is greatly appreciated.

No prob, I know the feeling, hope the suggestions help.



Great list to have printed, for sure.

Thanks again[/QUOTE]

[barnett468]

Hi again Tri Again;


Just general info:

The coils in the stator don’t really wear out or get weak with age. It is just a bare strand of wire wrapped around a bar. Either they work or they don’t.

The main causes of weak spark I have seen are a weak/bad ignition coil and/or weak magnetism on the stator flywheel.

The flywheels actually loose magnetism with age. The lower the magnetism, the lower the voltage to the coil and therefore the weaker the spark is.

I mentioned this to one person here a while back that had a weak yellow spark and he slapped some neo magnets on his stator flywheel for a day or so to re-magnetize it and then checked the spark afterwards using all the same other parts and he said the spark looked noticeably stronger.

The cause of his problem ended up being a muffler that was plugged up with nuts from the squirrels, lol.

If you have a weak yellow spark, it is most likely caused by the ign coil or weak stator flywheel magnets. These bike all had a bright blue spark when they were new. You van buy neo magnets by the roll from ebay cheap if you want.

[DohcBikes]

LOL!!!! FINALLY, a tutorial on how to respond line by line hahaaaaaaa, by the man himself:lol: That's the one I'm printing out, THANKS BARNETT:beer

Good luck tri----hope you find the gremlin!!!

[barnett468]

LOL!!!! FINALLY, a tutorial on how to respond line by line hahaaaaaaa, by the man himself:lol: That's the one I'm printing out, THANKS BARNETT:beer

Good luck tri----hope you find the gremlin!!!LMAO, Hey, I can even show you how to break up quotes and quote each line, word or even individual letter if desired or put multiple quote boxes inside one big one. :w00t:

Someone here showed me how. I think there's a reward for any information that helps lead to that persons identity.


PS - I didn't forget about sending you the Holley and Ford main jet/drill size chart you requested.

[DohcBikes]

LMAO, Hey, I can even show you how to break up quotes and quote each line, word or even individual letter if desired or put multiple quote boxes inside one big one. :w00t:

Someone here showed me how. I think there's a reward for any information that helps lead to that persons identity.


PS - I didn't forget about sending you the Holley and Ford main jet/drill size chart you requested.

Well aware of your quoteable craftsmanship LOL, I think I may have donated $10 or so to that reward fund:D

I'll be waiting on the chart.... and tri again to find his problem, sounds electrical to me so far

[captain2207]

Wow,thanks for some great info.besides eBay who else might carry neo magnets?wouldn't mind trying this...

[tri again]

Wow,thanks for some great info.besides eBay who else might carry neo magnets?wouldn't mind trying this...

I LOVE those neodymium magnets.
10 or 12 mm by ?? and they fit perfectly on the end of the gear oil drain bolt and engine bolt. to attract metal particles.
One of those the size of a pencil reaser will pick up a 12" cresent wrench.

Not sure, but I think strong magnets MAY draw mag power from the weaker one.
I'll have to check it out with a magnet and screwdriver.

[barnett468]

Wow,thanks for some great info.besides eBay who else might carry neo magnets?wouldn't mind trying this...
computer and electronic supply stores and the links below.

http://www.amazon.com/Neodymium-Magnets-inch-Disc-N48/dp/B001KV38ES

http://www.google.com/search?q=neodymium+magnets&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a


an electromagnetic charger will also work if its strong enough and will be much faster.

http://www.ehow.com/how_5040361_charge-magnet.html






Not sure, but I think strong magnets MAY draw mag power from the weaker one.
I'll have to check it out with a magnet and screwdriver.

i'll look for the guys link that did it here so you can see how.


charging magnets with magnets

"Magnets that have lost their strength Sometimes you can recharge a magnet that has lost some of its original charge. If you can find a very strong magnet, repeatedly rub it across your weakened magnet. The strong magnet will realign the magnetic domains inside the weakened magnet [source: Luminaltech].

Magnet stacking One way to make weak magnets stronger is by stacking more of them together. There's a big problem with this, though. Magnets attract each other in opposite directions, which will lower their overall strength. If you can find a way to hold or clamp them together, so they're aligned in the same direction, they will in fact produce a stronger magnetic field [source: Balbach]."

http://science.howstuffworks.com/how-to-make-magnet-stronger.htm




"The point of all this is that if you line up two magnets so their fields align with each other the magnets will stay magnetised, and can even increase in strength if you wait long enough (though you'd be waiting a long time). The converse it that if you line up two magnets so their fields oppose, e.g. north pole to north pole, and wait long enough their net magnetisation will decrease.

In both cases the change in net magnetism is due to thermal fluctuations within the iron, which is slow at room temperature. You can speed up the process by hammaring the magnets."

http://physics.stackexchange.com/questions/37989/will-two-magnets-lose-magnetism-if-they-stick-to-each-other-for-infinitely-long




send it out to be done below.

http://www.scooterwest.com/item_details/Flywheel-Re-Magnetizing/4045


other sources for the service

http://www.google.com/search?q=magnetizing+a+flywheel&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a