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jonboy688

Help: 2012 520rs suddenly spitting & sputtering

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Trying to help a friend with his beta. Was running fine and all of sudden started to spit and sputter and now won’t take any throttle. I assume it needs a carb clean.... few question if I may.....

 

What is the little vac diaphragm on the left side by the carb? Assuming it is something emission related and if so can it be removed?

How in the world do you remove the spark plug if you don’t have the tool kit?

And websites to see part diagrams like the other big name Manufactures have? Not sure on the hours or miles on the bike just trying to help a friend get his bike going again.

And is there a thread showing how to delete all the emission items? I searched and didn’t have any luck finding one.

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Think that is the acceleration pump, so don't remove Take her to your closest MX dealer for an ultrasonic bath. Next time let the float chamber run dry untill it stalls, no more problems, ever!

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i finally found the link to the pdf from beta on removing the emission stuff.... so are you saying to get it to start and turn the fuel off and let it idle till it dies? 

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Prior to shutting down a "clean" carb, turn the fuel off and let it run out of fuel. The pilot jet clogs so fricking easy. I run fuel filters on both sides of my IMS fuel tank, and even then the crappy fuel we get today is so full of garbage mine will clog if I leave the fuel "on" for a few days. 

 

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Got the emission stuff removed from the bike thanks to beta’s pdf. I got it to run but would only run for about a min then cut off. Didn’t matter whether it was idling or reved up a little. Cut the gas off and drained the bowl and see if anything changes tomorrow. I believe the carb is slam full of gas as it’s leaking around the choke shaft

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Got the emission stuff removed from the bike thanks to beta’s pdf. I got it to run but would only run for about a min then cut off. Didn’t matter whether it was idling or reved up a little. Cut the gas off and drained the bowl and see if anything changes tomorrow. I believe the carb is slam full of gas as it’s leaking around the choke shaft

These 4-strokes all came with float settings too high creating leaks, lots of data on this, take the carb off, Clean. Clean all jets reassemble.
If you do this, most likely be fine !

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12 hours ago, Mark-us-B said:


These 4-strokes all came with float settings too high creating leaks, lots of data on this, take the carb off, Clean. Clean all jets reassemble.
If you do this, most likely be fine !

best way to remove the carb is to swing the subframe up? or will it come out the side without swinging the subframe up?

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best way to remove the carb is to swing the subframe up? or will it come out the side without swinging the subframe up?

Everyone has their own ideas, but for me I loosen the subframe undo the carb clamps, move subframe slightly rearward and remove carb. A few times I did this without taking the carb away from the bike, just turned it horizontal to remove the float bowl to reset float height remove all jets and cleaning as much as possible in that position. While extra care needs to be taken if leaving the upper carb controls in place so not to damage anything.

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Well removed the carb when I got home this afternoon. Carb was surprisingly clean inside, removed all the jets and cleaned them with carb clean and blew them out with compressed air, none of them were stopped up. Blew out the out the passages in the carb and reinstalled it. No change at all, it took a while to start and when it finally would start it would only idle for about a min before it would shut back off. I am lost and guessing it’s either the petcock if stopped up or the float needs to be set lower.

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Did you loosen the gas tank cap, the one way valve F’s up sometimes remove the one way valve and install a regular style tank vent

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On 3/13/2019 at 3:53 PM, Mark-us-B said:

Prior to shutting down a "clean" carb, turn the fuel off and let it run out of fuel. The pilot jet clogs so fricking easy. I run fuel filters on both sides of my IMS fuel tank, and even then the crappy fuel we get today is so full of garbage mine will clog if I leave the fuel "on" for a few days. 

 

DON'T do this. You leave enough fuel in the bowl that it will turn to varnish or green fuzz.

Tilt the bike down to the ground a let all the fuel run out. Lay it down on it's side on both sides.

This will get all the fuel out.

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12 hours ago, jonboy688 said:

Well removed the carb when I got home this afternoon. Carb was surprisingly clean inside, removed all the jets and cleaned them with carb clean and blew them out with compressed air, none of them were stopped up. Blew out the out the passages in the carb and reinstalled it. No change at all, it took a while to start and when it finally would start it would only idle for about a min before it would shut back off. I am lost and guessing it’s either the petcock if stopped up or the float needs to be set lower.

If the bike EVER ran well with the jetting it has now, the problem is not the jetting. 

Blowing out the passages with air does not remove anything but fluid. You need to ream the passage ABOVE the pilot jet with a piece of single copper from a piece of cat 5 cable.  The idle circuit is affected by pilot jet, pilot passage, hot start, and fuel screw. All of those must be like new to get a good idle.  Does the hot start work, and does the cable move freely?  If not, the hot start plunger or cable are probably corroded, and hanging up the hot start plunger. Inspect.  The fuel screw must have a good oring, and be adjusted to 1.5-.175 turns out (to start with).  

The diaphragm on the side of the Carb is the ACV system (automatic coast valve), and it is not the problem and does not need service.

If you turn the throttle and the carb does not respond, that means your are lean, caused by fuel starvation. If it sputters, you are not looking at a carb problem, unless you put the slide plate in upside down (the hole goes on the bottom).

If the bike runs at idle, but will not idle steady, or if it 'sputters' or backfires with throttle, chances are the problem is NOT jetting, but a cam timing or a electrical issue.

I would change the plug, inspect the plug cap and HT lead, inspect all the grounds on the bike for corrosion, indpect the stator harness plug for corrosion,  and then do a stator test for a damaged winding.

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30 minutes ago, KRAYNIAL said:

If the bike EVER ran well with the jetting it has now, the problem is not the jetting. 

Blowing out the passages with air does not remove anything but fluid. You need to ream the passage ABOVE the pilot jet with a piece of single copper from a piece of cat 5 cable.  The idle circuit is affected by pilot jet, pilot passage, hot start, and fuel screw. All of those must be like new to get a good idle.  Does the hot start work, and does the cable move freely?  If not, the hot start plunger or cable are probably corroded, and hanging up the hot start plunger. Inspect.  The fuel screw must have a good oring, and be adjusted to 1.5-.175 turns out (to start with).  

The diaphragm on the side of the Carb is the ACV system (automatic coast valve), and it is not the problem and does not need service.

If you turn the throttle and the carb does not respond, that means your are lean, caused by fuel starvation. If it sputters, you are not looking at a carb problem, unless you put the slide plate in upside down (the hole goes on the bottom).

If the bike runs at idle, but will not idle steady, or if it 'sputters' or backfires with throttle, chances are the problem is NOT jetting, but a cam timing or a electrical issue.

I would change the plug, inspect the plug cap and HT lead, inspect all the grounds on the bike for corrosion, indpect the stator harness plug for corrosion,  and then do a stator test for a damaged winding.

i ran my little welding tip cleaners thru the jets, and could see thru them before and after.... i am leaning towards the float height, as it will run for that small period of time.... almost like someone shut the gas off

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2 hours ago, jonboy688 said:

i ran my little welding tip cleaners thru the jets, and could see thru them before and after.... i am leaning towards the float height, as it will run for that small period of time.... almost like someone shut the gas off

Ream the pilot passage.... 

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Check ignition coil cables, my RR480 had same sympton. Connector of the low voltage cable was the cause.

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4 hours ago, patjis said:

Check ignition coil cables, my RR480 had same sympton. Connector of the low voltage cable was the cause.

Got any pictures of which cable you're talking about?

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18 hours ago, patjis said:

Check ignition coil cables, my RR480 had same sympton. Connector of the low voltage cable was the cause.

not sure i understand what the low voltage connector is?

 

i am deft leaning towards it is spark related now, i have had the carb on and off about 7 times now adjusting the float height and no change in the outcome at all, every passage is clear and clean, petcock from tank flows fine, emissions stuff removed... still about 30-45 secs after it will start it just cutts off no matter if idling or held at part throttle 

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1 hour ago, jonboy688 said:

not sure i understand what the low voltage connector is?

 

i am deft leaning towards it is spark related now, i have had the carb on and off about 7 times now adjusting the float height and no change in the outcome at all, every passage is clear and clean, petcock from tank flows fine, emissions stuff removed... still about 30-45 secs after it will start it just cutts off no matter if idling or held at part throttle 

I would pull the harness connections after the stator and inspect

Edited by KRAYNIAL

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