Not running right...

Hi guys, having problems with the running of the motor, seems to be missing kind of, runs mint up a hill or under a bit of load, or to start with, then once up to speed its seems to be going from the sweet sound to a rough sound, I've checked the carb, all good there, plenty of spark, plug is black though, I'm thinking it could be my mix or the oil I'm using, it's been the same from when I got it really, just seems weird that's it's at mid to full speed, but more often it's just like it all the time from go to top speed. .....
Doing my head in....

HELLLLLLLL.LP
fuel filter.. fuel line, contaminated gas.. bad plug, airscrew,,clo0gged air filter... chk list goes on... on.. dont give up..YOU CAN FIX IT!
 
Going back to the original post, there is no mention of what spark plug is being used. If it is the original factory plug, that could be the problem. In my opinion, they do not keep up with a two cycle engine resulting in 4 stroking like symptoms at high rpms. If this is the case, I could suggest using a iridium plug like the warm (Illinois USA) weather NGK model BPR7HIX plug. This does not seem to increase top end as much as I would expect, maybe a couple of extra mph, but the engine runs at a higher speed on downhill grades and seems to get noticeably warmer. During cooler times of the year, especially when riding into the wind and uphill, the engine does not seem to stay warm enough. The seasonal use of a hotter plug noted by a change in the middle number may help. If electronics are used on the bike, like a digital speedometer or a back up camera, try to find a resistor type plug so as not to chink the flash memory .

I see that you live in down under New Zealand. From what I have seen on Netflix recently, riding in a upside down situation my be affected by something hard to explain.
 
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Going back to the original post, there is no mention of what spark plug is being used. If it is the original factory plug, that could be the problem. In my opinion, they do not keep up with a two cycle engine resulting in 4 stroking like symptoms at high rpms. If this is the case, I could suggest using a iridium plug like the warm (Illinois USA) weather NGK model BPR7HIX plug. This does not seem to increase top end as much as I would expect, maybe a couple of extra mph, but the engine runs at a higher speed on downhill grades and seems to get noticeably warmer. During cooler times of the year, especially when riding into the wind and uphill, the engine does not seem to stay warm enough. The seasonal use of a hotter plug noted by a change in the middle number may help. If electronics are used on the bike, like a digital speedometer or a back up camera, try to find a resistor type plug so as not to chink the flash memory .

I see that you live in down under New Zealand. From what I have seen on Netflix recently, riding in a upside down situation my be affected by something hard to explain.
Cheers mate, yeah I thought about that too being upside down lol, might explains the gas falling out of the petrol cap hahahaha, trying a new smaller jet and stock exhaust and see what happens ...
 
Going back to the original post, there is no mention of what spark plug is being used. If it is the original factory plug, that could be the problem. In my opinion, they do not keep up with a two cycle engine resulting in 4 stroking like symptoms at high rpms. If this is the case, I could suggest using a iridium plug like the warm (Illinois USA) weather NGK model BPR7HIX plug. This does not seem to increase top end as much as I would expect, maybe a couple of extra mph, but the engine runs at a higher speed on downhill grades and seems to get noticeably warmer. During cooler times of the year, especially when riding into the wind and uphill, the engine does not seem to stay warm enough. The seasonal use of a hotter plug noted by a change in the middle number may help. If electronics are used on the bike, like a digital speedometer or a back up camera, try to find a resistor type plug so as not to chink the flash memory .

I see that you live in down under New Zealand. From what I have seen on Netflix recently, riding in a upside down situation my be affected by something hard to explain.
Using standard plug at the mo as well
 
I have been having a similar situation with my HP carb, but I am not getting enough fuel. My plug is brown and dry like it is too lean. I have good bottom-end, but it reaches a point near WOT where it runs ruff and looses power. This high performance carb is different than the NT, it has a gate instead of a needle. I have a spare one so I am going to see if it can be modified to deliver more fuel at the top end.
Let me know how ya get on..
 
Pissed around with it today, put the c or e clip back to centre, 40ml oil to 1 litre gas, back to where I was, runs normal at low revs, above half throttle turns ruff, so ordering a smaller get this week, See how we go with that. Will go back to stock exhaust as well as some say it's to long for a 2 stroke.
 
58 Triumph
Hey mate :)
Gert a wire gauge, i had to get one because the jets i ordered off ebay long ago were stamped a # sign then the supposed number, for instance my #68 seemed to be bigger by two sizes.
Something simple it seems man, don't get discouraged.
 
I use a RT (RunTong) carb, Dellorto clone but when i ran the NT carbs i always set the c clip to the second notch from the top, then i just messed with the jets to tune it.
But as stated above, those jet numbers can be off so get that wire gauge when you can.
 
Get some jets too. From #60 up to #80, mess around with them and you will find a good one. Keep the Exhaust ;)
 
Get a #68 and a #66 which the later I don't think you'll need. Probably to pricey to order form SBP from USA. If you can find real dellorto jets in your hood they will be accurate. Else wise you will need micro bits or jet gauge to check correctness of sizing. Then you need a caliper to check the gauges cause depending on where you get them they could be as inaccurate the jets. Reassuring ay.
 
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