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  #11  
Old 06-04-2016, 05:38 AM
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Put in a 40 pilot jet, 2 turns out results:

***********************PLUG CHOP TEST-SORT OFF....******************



***********************PLUG CHOP TEST******************



************************After 15 minutes of normal riding in the city (riding like it trails, when given a straight I made it scream like it should *************************







************************************************** ***






Last photos show that spooge was actually very minimum this time.

In conclusion HEAT issue is solved.. I think, the pipe is not as hot and the engine itself is way cooler (As it used to be) I can now unscrew the spark plug using my fingers (when it was with a 42 pilot the spark plug itself was melting hot outside)

Can anyone tell me anything about the spark reading, after spark plug chop test, the insulator was actually still white and only brownish at the very bottom..

From feel the bike is running very crips and clean, no extra smoke coming out from exhaust, although after changin pilot i feel i need to go to even bigger main jet (from 165 to 168)
Although after 15minutes of riding the new spark plug started showing signs of little "Carbon'? deposits i believe.. (The old one was covered in carbon deposits)

So any ideas is the mixture alright?

BIKE SETUP:
98 octane gas (from a gas station)
Oil mixed in gas: Motul 800
Oil/gas RATIO: 1:50 (20ml per liter)
Outside temperature: 22 celcius.
JETS:
Main: 165
Pilot: 40
Air screw: 2 and 1/4 turns out.
Needle: 2 position from the bottom.

Feel: Runs crisp without any hesitation or bogging

Last edited by Simonas; 06-04-2016 at 12:18 PM.
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  #12  
Old 06-04-2016, 05:05 PM
2 stroke bloke's Avatar
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You'd think it'd run hotter with the leaner pilot jet.

I did say it's hard to read a new plug lol. Looks OK from the pics though IMO.
I'm not big on chop tests. Didn't even do them in my Karts. Actually, I think they're BS. Feel and sound is where it's at. IMO.

Is the clip on the carby needle 2nd clip from the top, or bottom of the needle?
If it's the bottom then I'd richen it. I normally run my clip 2nd from the top. You could maybe start on the middle clip with a 168.

You could also consider fitting a hot plug/Iridium plug/racing plug. They're much more efficient. Hang on and I'll post a vid.

Spooge is what comes out of the silencer and power valves etc. The nasty, black, sticky, goo.

---------- Post added at 09:05 AM ---------- Previous post was at 08:42 AM ----------

Be way too easy if the vids were on you tube. I HATE facbook with a passion!!

Anyway. There's two vids in the link. Both showing a spark plug in the thumb nails. 1st one is about 4 seconds long, 2nd is around 9 seconds.

One is showing the spark on a stock plug, the other is showing the spark on a hot plug.

Checkout the differenence.
https://www.facebook.com/TwoStrokePe...=page_internal

The hot plug will obviously burn the fuel/gas, more efficiently.

Last edited by 2 stroke bloke; 06-04-2016 at 04:59 PM.
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  #13  
Old 06-06-2016, 11:35 PM
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glad you got your problem solved but is strange, in reality you cannot tell if your engine is running hot or not just by unscrewing the spark plug by hand, you should get a temp meter to measure coolant temp to check if it running hot or not.

another thing to consider is that if there is carbon build up inside the cylinder head or exhaust pipe then that could cause the engine & pipe to run at a bit higher temperature because carbon works as an insulator/heat buffer, so it is good to check these two.

also running lean will make the engine run hotter but could be fuel related issue in this case (maybe clogged jet or something) and got cleared up when you disassemble the carb to change the jet. also check your air filter to be clean and oiled, if it has gunk/dirt on it will work a bit rich and engine wont run well. if the engine does not clear up in mid rpms try the needle clip in the middle position.

2strokebloke what do you mean by a "hot plug"? a non-resistor?
from the videos the behavior of the spark on the plain plug is normal because the tip is not thin as iridium, you should check the spark on the normal plug at higher rpms 4000-6000, should be nice and fat spark all around the tip I agree that the iridium (or even the BR8EG plug) give a more consistent spark, though it would not cause an issue on engine running but it would last longer for sure.
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  #14  
Old 06-10-2016, 06:26 AM
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Quote:
Originally Posted by byronk View Post
glad you got your problem solved but is strange, in reality you cannot tell if your engine is running hot or not just by unscrewing the spark plug by hand, you should get a temp meter to measure coolant temp to check if it running hot or not.

another thing to consider is that if there is carbon build up inside the cylinder head or exhaust pipe then that could cause the engine & pipe to run at a bit higher temperature because carbon works as an insulator/heat buffer, so it is good to check these two.

also running lean will make the engine run hotter but could be fuel related issue in this case (maybe clogged jet or something) and got cleared up when you disassemble the carb to change the jet. also check your air filter to be clean and oiled, if it has gunk/dirt on it will work a bit rich and engine wont run well. if the engine does not clear up in mid rpms try the needle clip in the middle position.

2strokebloke what do you mean by a "hot plug"? a non-resistor?
from the videos the behavior of the spark on the plain plug is normal because the tip is not thin as iridium, you should check the spark on the normal plug at higher rpms 4000-6000, should be nice and fat spark all around the tip I agree that the iridium (or even the BR8EG plug) give a more consistent spark, though it would not cause an issue on engine running but it would last longer for sure.
First thing i did was clean the carburator (all jets everything!) Didn't help.
You see, someone mentioned that a rich condition might be spitting unburn't fuel into pipe and then lighting it on fire in the pipe itself ( what was probably happening to me because my pipe turned purple)
After a leaned out the mixture the overall temprature dropped a lot.

Started of with a clean air filter, fresh gas, no air leaks

Pipe is almost carbon free (cleaned it with a torch and when the catalyst was removed it was all carbon free inside ( about a half a year ago)

The main thing i can say when the pilot was 42, I couldn't even unscrew the spark plug with bare hands, because of the tempreture it was giving. (very hot) (yes it was tighten all the way in, same thing like 15 times)

with a 40 pilot, spark plug is nice and cool and easy to unscrew, engine side covers are easy to touch, before the change, they were hot.
(in conclusion I felt a BIG cooling difference)

Now I got the needle clip to third from the bottom, (was on second from the bottom) ,installed a 168 main (was 165), will be giving some testing on sunday, see how that works, spark plug is now strangely dry (looks like it burns very well, although a bit too black)
We'll have to wait and see how it turns out
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  #15  
Old 06-14-2016, 12:14 PM
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@@@@@@FINAL CONCLUSION@@@@@@@@@@@
Bike really needed a 38 pilot jet (was size 42)
And it needed a bigger main jet 168 (was size 162)
Needle stayed on stock setting (second shelf from the bottom position)
Probably because of an aftermarket air filter.


Heat problem was most likely because of unburnt fuel thrown into the pipe (big amounts) being lit on fire and producing even more heat in the pipe.

Bike runs crisp and clean A BIG DIFFERENCE!
Plug looks perfect, choco brown, idles perfectly and throttle response is phenominal.

Would advice anyone to start jetting their bikes correctly!
Lessons learned: I can now tell the difference between lean and rich mixture.

A BIG THANKS FOR ALL OF THE ADVICE!



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  #16  
Old 06-14-2016, 05:22 PM
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Good stuff mate. Glad you got it sorted.
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