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Tanker_01 02-08-2019 11:03 AM

Yeah I really wish mine had the OEM carb when I got it. I may ask the PO if he still has it.

Tanker_01 02-09-2019 08:47 AM

Ok so I think I have the chinese carb I have working somewhat. I am adjusting idle from the thumb throttle and I have the mixture screw 2 turns out. I have the needle set on the 2nd from the top.
I took it for a ride around the house last night and I had quite a bit of white smoke now coming out of the exhaust and It does not seem to be running correctly. I did not have the oem snorkel on the airbox so that may have contributed a little to the bad running but the smoke concerns me. I know it has really good compression so I am thinking maybe valve seals are letting some oil past. I did not ride it long enough to find out if it stops after a while. I also put a gas cap that shows fuel level from a polaris bike but it doesnt have a vent, that may also have contributed to the bad running. I talked to the PO and he has the original carb and is going to mail it to me so I got that going for me. I still need to give it a good wash so it isnt all muddy and I am going to do an oil change and the valve clearances as well. Im not too worried about the smoky exhaust at the moment but I may put a little marvel mystery oil down into the cylinder just for good measure.

sr.ruedas 02-09-2019 12:23 PM

White smoke? You did not put your location in your header, so this could be primarily water vapor in a cold climate.

If you have the air filter on, then the snorkel tube does not add much air resistance (if not full of nuts).

Did you look at the sparkplug to see what color it is? You prob want the main jet needle set in the second slot up
from the bottom, i.e. one toward the rich side. Your setup sounds like one toward the lean. Any signs of lean
mixture?

Is the cold start enrichening valve working?

Tanker_01 02-09-2019 04:20 PM

I am in southern Indiana. I suppose it was about 25 degrees when I took it for a ride (it was 60 the day before). I will check the plug when I get a chance and see how it looks.

Is the cold start enrichening valve the choke?

sr.ruedas 02-09-2019 05:33 PM


Originally Posted by Tanker_01 (Post 3412648)
Is the cold start enrichening valve the choke?

Got it. Cold. I am originally from the Midwest myself. Hopefully just vapor at the exhaust.

The cold-start valve opens a passage in the carb body that lets in more fuel. Not a choke. A choke is a plate that blocks the inlet of the carb, which increases the vacuum inside and causes fuel to be sucked up the main jet.

The intent is the same, so both are often called a "choke". These days, you still find chokes on small carbs, up to 100cc or so.


Tanker_01 02-09-2019 05:39 PM

As far as I can tell it works. I dont have very much experience on these diaphram carbs. Im more used to vintage dirtbike carbs which are much simpler. When I push the cold start lever forward it starts cold easier if that means its working then I guess it is.

Tanker_01 02-11-2019 07:31 PM

I think I figured out why it was running badly and smoking. There is a little ring that is supposed to be on top of the needle and it was under the E ring instead, when the needle was pulling up it was getting stuck and dumping fuel into the intake. I put the E ring at the second from the top position and it now starts right up and runs great with the 'choke' on. It is ride-able but it does not rev up to 50-80% throttle. It also doesn't want to run with the 'choke' off. Does that sound like a fuel screw issue or a needle E ring position issue?

I also wired and mounted my winch up and it looks and works great! I replaced the lights that came on it with some I had from a Scrambler. I also blew a fuse somehow so I now temporarily have a wire jumper fire hazard fuse... Im planning to make a handlebar mounted light as well as a rear spot light. I also have a voltage meter to wire up as well. Still have to put the new CV boots on, those came in today as well. Is there any bad track records with lifting these bikes? I design lift kits for UTVs for my job so I could easily fab up a bracket set for this one.

https://cimg7.ibsrv.net/gimg/atvconn...650c2cee29.jpg


sr.ruedas 02-11-2019 08:32 PM


Originally Posted by Tanker_01 (Post 3412833)
I put the E ring at the second from the top position and it now starts right up and runs great with the 'choke' on. It is ride-able but it does not rev up to 50-80% throttle. It also doesn't want to run with the 'choke' off. Does that sound like a fuel screw issue or a needle E ring position issue?

That's good data. It means your cold-start is working, and it also is a classical sign of lean condition. The needle clip should arrive new in the middle position. Sounds like you need to move the clip down one to the middle, or even 2 slots (richer). Don't forget to read the plug.

If you raise the suspension, remember that you have 4 wishbones, so 16 pivot points. Sounds like a big job.


Tanker_01 02-12-2019 06:04 AM

I will move the clip and see if it runs better. Im just relieved Im not going to be doing rings any time soon. I will also pull the plug tonight and see how it looks. The new plug should be here soon.

If I do raise the suspension it will just be by standing the shocks up more and down about 10mm. I think I could get 1"-2" out of that. I could do it in 4 brackets on the upper shocks. That will be after new tires and after the CV boots get replaced. Absolute bottom of the list.

sr.ruedas 02-12-2019 12:10 PM

Also, the pilot screw should be initially set (when you can get to it) at whatever the service manual says. If no manual, then
1-2 turns out. I have a special tool to help adjust this with the engine running, but it is still hard to get to. It is not the most critical
setting anyway. The low-speed fixed jet and main jet/needle are more important.


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