2 stroke jetting

finlay vanmulbregt
Edited Date/Time 6/26/2020 8:44am
I have brought a lectron for my rm125 and it is a real struggle to start but once running it seems to run alright. Wondering if I need to adjust the rod to richen it out. I’ll put some photos of the spark plug in after about an hour of riding. Would really appreciate some help



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jaguar57
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jaguar57 6/24/2020 4:49pm
6/24/2020 4:49pm
it's just a tad on the rich side but that could be due to using a very basic group 1 or 2 engine oil instead of a good semi or full synthetic oil. Keep in mind that the plug shows the jetting at the RPM most used.
finlay vanmulbregt 6/24/2020 5:55pm
6/24/2020 5:55pm
jaguar57 wrote:
it's just a tad on the rich side but that could be due to using a very basic group 1 or 2 engine oil instead of...
it's just a tad on the rich side but that could be due to using a very basic group 1 or 2 engine oil instead of a good semi or full synthetic oil. Keep in mind that the plug shows the jetting at the RPM most used.
What makes you say it’s rich. And no I’m running motul 800.
jaguar57
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jaguar57 6/24/2020 7:20pm
6/24/2020 7:20pm
from the little bit of black I'd say it's 2 or 3% rich. That's probably 1 size difference on the main jet. Make sure you buy genuine jets from Sudco or Niche Cycle. If you have a non-genuine jet in it then your genuine jet won't be right because non-genuine jets have hole sizes that vary widely from what they should be. There's a popular source that claims they sell genuine jets but I bought a few and measured the hole size using micro drill bits and the sizes were way off. I won't mention them here.
jaguar57
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jaguar57 6/24/2020 7:24pm
6/24/2020 7:24pm
Oh and I'd be willing to bet you're a 32:1 person no matter what oil you use which is 50% more oil than what is necessary with Motul 800 Off Road.

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Richard Tease II 6/24/2020 8:32pm
6/24/2020 8:32pm
jaguar57 wrote:
Oh and I'd be willing to bet you're a 32:1 person no matter what oil you use which is 50% more oil than what is necessary...
Oh and I'd be willing to bet you're a 32:1 person no matter what oil you use which is 50% more oil than what is necessary with Motul 800 Off Road.
Hey Jag
I see your an oil guy. We run Yamalube R which were told is re branded Motul 800.
Looks the same smells the same and smell out of the exhaust is the same.
You heard any truths to this rumour?
jaguar57
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jaguar57 6/24/2020 8:51pm
6/24/2020 8:51pm
No, Yamalube is a good product but it has basic mineral oils, not synthetic oil. Typical ratio for it is 28:1 but for Motul 800 Off Road it is 50:1 (for a 125 motocrosser. For a 250 the ratios are higher)
Chris99Flannery 6/25/2020 1:49am
6/25/2020 1:49am Edited Date/Time 6/25/2020 1:50am
Jag can you do Pro Kr2 on a 125, on the pipe pulling an 86kg rider? thanks currently using 28-1.
jaguar57
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jaguar57 6/25/2020 10:38am
6/25/2020 10:38am
never heard of it. First we need full specs on the oil which isn't always available. My rule is that if the manufacturer doesn't provide full specs then they are hiding something and I don't want to support them by buying their mystery product. Go to my site at www.dragonfly75.com/moto/oil.html and choose one of the oils listed.
Chris99Flannery 6/25/2020 6:05pm
6/25/2020 6:05pm
jaguar57 wrote:
never heard of it. First we need full specs on the oil which isn't always available. My rule is that if the manufacturer doesn't provide full...
never heard of it. First we need full specs on the oil which isn't always available. My rule is that if the manufacturer doesn't provide full specs then they are hiding something and I don't want to support them by buying their mystery product. Go to my site at www.dragonfly75.com/moto/oil.html and choose one of the oils listed.
Fuchs Silkolene Pro KR2 castor/synthetic..
Similar to 927, a747 etc
jaguar57
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jaguar57 6/25/2020 7:12pm
6/25/2020 7:12pm
I see it's similar to Castor 927 which means you are using about twice as much oil as you should and probably getting half life from your plugs and having to clean the exhaust valves too often. To read about my spreadsheet for finding out the right ratio go to www.dragonfly75.com/moto/oil2.html
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GoggleFiend904 6/25/2020 7:59pm
6/25/2020 7:59pm
jaguar57 wrote:
I see it's similar to Castor 927 which means you are using about twice as much oil as you should and probably getting half life from...
I see it's similar to Castor 927 which means you are using about twice as much oil as you should and probably getting half life from your plugs and having to clean the exhaust valves too often. To read about my spreadsheet for finding out the right ratio go to www.dragonfly75.com/moto/oil2.html
Some really good information. I’m going to PayPal you and shoot you an email from tierrabmx@gmail.com
SimonGreen 6/26/2020 8:44am
6/26/2020 8:44am
Fantastic stuff Jag. I'll drop you a few quid via Paypal also.. the best content I've found to date on this often misunderstood and miscommunicated aspect of running a two stroke..

I must also add that the ethanol removal process is cool! I can still get ethanol free fuel at the mo but it's not going to stay that way for long..

Thanks again..

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