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  #21  
Old 12-28-2016, 01:59 AM
DarkWolf2k DarkWolf2k is offline
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Default Re: Engine won't start.

Quote:
Originally Posted by Agreen View Post
Terminology time:

4 stroking - when the engine is "sputtering" or has that "machine gun" feel. Due to having too much fuel (rich)

Bogging - A notable drop in power, without any other strange noises. Sounds like (and feels like) the engine is just spinning down and not producing power. This is due to a lean condition (too little fuel)

Now, the situation you described above with turning off the fuel sounds like it is just normally running too rich. Once the bowl starts to empty, you start to experience a short moment of correct air/fuel mixture and it runs good for a second, then runs out of fuel and bogs entirely.

That could mean a couple things. One possibility is that you are running your oil mix too thin. More oil per part of gas makes the air/fuel mixture more lean. Less oil means a more rich condition. You're experiencing a "too rich" condition, so try a higher oil/fuel ratio? What is yours currently, and how do you mix it?

Another cause can be the needle. It's connected to the carburetor slide with an "e-clip". Move the clip up to go lean, but this only adjusts air/fuel mixture up to about 3/4 throttle.

If changing your gas/oil mix and moving the needle doesn't help, I'll step you through re-jetting the carb.
Oil mix was moved from 16:1 to 20:1 as per instructed by the manual though that was running fine for quite some time before this. It's mixed in a 1 gallon a bit at a time with a predetermined amount of oil for 2 stroke engine oil. Definitely feels like 4 stroking from the explanation.
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  #22  
Old 12-28-2016, 07:10 AM
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Agreen Agreen is offline
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Default Re: Engine won't start.

Wow that's a heavy mixture. So it's obviously not the gas mixture. It's "recommended" by the manufacturer to go that heavy on the oil, but 24:1 is a reasonable starting point, moving on to 36:1.

Anyway, move the needle clip up a notch or 2 and see what happens.
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  #23  
Old 12-28-2016, 08:51 PM
DarkWolf2k DarkWolf2k is offline
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Default Re: Engine won't start.

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Originally Posted by Agreen View Post
Wow that's a heavy mixture. So it's obviously not the gas mixture. It's "recommended" by the manufacturer to go that heavy on the oil, but 24:1 is a reasonable starting point, moving on to 36:1.

Anyway, move the needle clip up a notch or 2 and see what happens.
It was sitting on the second one down from the top so I moved it up to the last one.
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  #24  
Old 12-28-2016, 09:01 PM
DarkWolf2k DarkWolf2k is offline
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Default Re: Engine won't start.

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Originally Posted by DarkWolf2k View Post
It was sitting on the second one down from the top so I moved it up to the last one.
There's definitely a noticeable improvement. It feels more like a machine gun firing then the more sporadic sputters before but no go.
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  #25  
Old 12-29-2016, 08:36 AM
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Agreen Agreen is offline
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Default Re: Engine won't start.

So there's one more thing to try before rejetting, and that's the ignition system. Replace the spark plug with an NGK B6HS. You can get it from any auto parts store for about $2. Gap it to 0.025".

The last effort has 2 paths. Either buy a set of jets, or buy the stuff to solder and drill your jets. And there's ups and downs for each path.

Buying Jets:
Pros
-easier
Cons
-they aren't all made equally (the jet orifices are randomly sized sometimes )
-I don't know any reputable sellers that you can buy them from (*cough gasbike cough*)

Drilling jets:
Pros
-More accurate
-I have a video that explains how to do it
--you can potentially get everything in local stores if you have an actual hobby store nearby
Cons
-not as easy

I'll dig up that video here shortly.
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  #26  
Old 12-29-2016, 08:39 AM
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Agreen Agreen is offline
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Default Re: Engine won't start.

Tuning basics:

https://youtu.be/l0s-aCPJf4c

Re-jetting :

https://youtu.be/PerfQbB45O0
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  #27  
Old 12-30-2016, 03:51 AM
DarkWolf2k DarkWolf2k is offline
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Default Re: Engine won't start.

I feel like a complete n00b. Looked around at 4 stroking and whatnot since I last posted and researched quite a bit and tried it a couple of times. I'm thinking about posting a video. I do believe it's still too rich though. It's very short bursts. Like small jerks. Wait for 2-3 seconds jerk again. Sometimes 5-6 seconds before another jerk. Deflooded the engine from trying to start it before cause it was literally reeking with gas and tried it again. There were more consistent jerks when I turned the gas back on after it filled with gas a bit but then it just seems to flood again. Would adjusting the float bowl actually do anything to help lean out the gas? I've got a multimeter ordered to check the electrical and I'll probably get the rest of the tools I don't have by early next month. Do I need a torch to heat the jet to use solder or could I just use a lighter? I don't know the temp solder needs to heat at in order to melt. My current spark plug is a BPR6HSA. Gap is unknown.
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  #28  
Old 12-30-2016, 08:50 AM
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Agreen Agreen is offline
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Default Re: Engine won't start.

Quote:
Originally Posted by DarkWolf2k View Post
I Looked around at 4 stroking and whatnot since I last posted and researched quite a bit and tried it a couple of times. I'm thinking about posting a video.

I'm glad you're doing the research! Most people would have thrown their hands in the air and given up by now. Unfortunately, it's real hard to describe problems and diagnose them without actually being in front of the bike. A video would be helpful.

Quote:
Originally Posted by DarkWolf2k View Post
I do believe it's still too rich though. It's very short bursts. Like small jerks. Wait for 2-3 seconds jerk again. Sometimes 5-6 seconds before another jerk. Deflooded the engine from trying to start it before cause it was literally reeking with gas and tried it again. There were more consistent jerks when I turned the gas back on after it filled with gas a bit but then it just seems to flood again.
That does sound too rich.


Quote:
Originally Posted by DarkWolf2k View Post
Would adjusting the float bowl actually do anything to help lean out the gas?
Maybe. Remember the question earlier about if gas was leaking out the air filter? I kind of got to wondering if the engine (and carburetor) are level or not. If the carburetor's air filter points up, it may be that the float isn't able to do its job (because of the angle) and gas may be pouring in the engine. Maybe.


Quote:
Originally Posted by DarkWolf2k View Post

I've got a multimeter ordered to check the electrical and I'll probably get the rest of the tools I don't have by early next month. Do I need a torch to heat the jet to use solder or could I just use a lighter? I don't know the temp solder needs to heat at in order to melt. My current spark plug is a BPR6HSA. Gap is unknown.
If not a torch, use a cheap soldering iron. They usually come with solder. Try to get the NON lead-free solder. Lead free stuff is harder to melt. Also, thinner solder is easier to melt.

That's a good spark plug, but expensive and unfortunately not worth it. Those will last 100,000 miles in cars. The B6HS (copper core, but otherwise the same) has a lower resistance (better for spark) and is designed to last 30,000 miles in cars. Either way, if they foul up (Google image search for "fouled spark plug") you should replace it. You could clean it, but it's hard to do right without a media blaster. And check the gap (spark plug gap tools are usually under $1 and found at the register at auto parts stores).
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  #29  
Old 12-30-2016, 10:04 AM
DarkWolf2k DarkWolf2k is offline
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Default Re: Engine won't start.

The spark plug was the only one they could link the chinese stock one to in O'Reilly's system that was also able to have it's crown taken off as per instructed by the manual. It's roughly about 2.99-3.19 each time so it's not too bad. I like the idea of a better spark so I'll try to keep that in mind. The carb is mostly level. Though it's off by 15-20 degrees. I'll check the float with it slightly off like it is when it's on the carb to see if it'll still float like that. Gonna be messing with it for a while more today to see if I can work some magic.
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  #30  
Old 12-30-2016, 11:32 AM
DarkWolf2k DarkWolf2k is offline
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Default Re: Engine won't start.

Warning: Do not use BPR6HSA as a replacement spark plug!!!!! It has apparently hit the top of the piston and slightly scratched it. I will be getting a B6 or B5HS.
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