Zongshen RX3 carbureted version mods & repairs - Page 3

SpudRider · 02-25-2015, 06:30 AM

Quote:

Originally Posted by FTEY

Confirmed there's a brass screw under that carb and it should be the PMS screw.
Problem now is getting there is a pain. Space is so small. Cant even get the smallest screwdriver in there let alone my hand or fingers. And with the hot engine right in front...... Unless you have an angled screwdriver or the long flexible ones.... Guess i need to send it to the shop to do it.

The PMS is not difficult to rotate. You can probably adjust it with a short screwdriver tip.

If that doesn't work, can you loosen the metal bands on each side of the carburetor, and rotate the carburetor so the bottom faces you? If so, you can adjust the PMS, and then rotate the carburetor back into a vertical position. Just make sure to tighten the metal bands again after you finish.

Adventore · 02-25-2015, 06:54 AM

Quote:

Originally Posted by FTEY

Confirmed there's a brass screw under that carb and it should be the PMS screw.
Problem now is getting there is a pain. Space is so small. Cant even get the smallest screwdriver in there let alone my hand or fingers. And with the hot engine right in front...... Unless you have an angled screwdriver or the long flexible ones.... Guess i need to send it to the shop to do it.

Can it be reached by the smallest ratchet? The smallest ratchet that I have is just 3 inches long. But I never tried before. Since the bike is still under warranty, I do agree to send it back to the shop. And that's what I'm planning to do this weekend.

FTEY · 02-25-2015, 09:10 AM

Quote:

Originally Posted by Adventore

Can it be reached by the smallest ratchet? The smallest ratchet that I have is just 3 inches long. But I never tried before. Since the bike is still under warranty, I do agree to send it back to the shop. And that's what I'm planning to do this weekend.

Adventore. U goin back to your shop or to the manufacturer in alma.

katoranger · 02-25-2015, 09:18 AM

Quote:

Originally Posted by SpudRider

I'd like him to count the number of turns first, so he knows the initial setting, Allen.

That is a good idea.

Adventore · 02-25-2015, 09:56 AM

Quote:

Originally Posted by FTEY

Adventore. U goin back to your shop or to the manufacturer in alma.

FTEY, I'm going back to the shop. Reason is the shop that I bought my RS3 helped the manufacturer to tune their prototype model when they are still setting up their manufacturing line at Alma. This is also why I went all the way from Penang island to this shop to buy from them. I have asked a lot of shops here but none of them know about KTN RS3 in detail. Only this particular shop answered all my questions.

I keen to learn from them as I might need those skills when I go around peninsula Malaysia one day with my RS3.

SpudRider · 02-25-2015, 03:30 PM

Quote:

Originally Posted by Adventore

FTEY, I'm going back to the shop. Reason is the shop that I bought my RS3 helped the manufacturer to tune their prototype model when they are still setting up their manufacturing line at Alma. This is also why I went all the way from Penang island to this shop to buy from them. I have asked a lot of shops here but none of them know about KTN RS3 in detail. Only this particular shop answered all my questions.

I keen to learn from them as I might need those skills when I go around peninsula Malaysia one day with my RS3.

You are wise to use your warranty coverage, and let the shop diagnose this problem.

You are wiser yet to watch, and learn as they fix the problem.

Thank you for your willingness to share what you learn.

thillskier · 02-25-2015, 04:37 PM

A flexible screwdriver Its shaft is "wire" and can bend almost 90 degrees, so turn handle horizontal plane, but tip is vertical (or very close to it

. You can chang to whatever kind of bit you need also, on the driver end. Very handy. They make a flex bit for drills also, you can use if you have one already.

The idea Spud suggested works well also, ie loosen the bands on the manifold, rotate carb, then adjust screw, and rotate carb back to vertical before testing. IT MAY run very rich, if the bowl dumps fuel into intake tract for a minute or so (or be flooded/hard to start for a few minutes).

There is a CHANCE the floats on both carbs are too high, and dumping fuel when starting out and or braking or tilting the bike from side to side at a stop. Try that (tilting the bike) and see if it stalls. Thats the way to find out re floats (one way w/o dissaasembly of carb).

If its floats, I can explain setting them for you as well. (Spud may have this covered already in his thread...)

Adventore · 02-26-2015, 06:04 AM

FTEY. My RS3 has been behaving good today. There are a few thing that I have change during my riding.

1) gear shifting behavior. I shift to higher gear after about 1/2 second after engaging the clutch. When shifting to low gear, I will rev the engine before shifting. I just gave a short rev to around 4000 RPM.
2) when engaging to first gear from neutral at stop light. I rev before engaging first gear.
3) engaging neutral. Short revving the engine, it should be easier to get neutral.
4) starting the engine from cold or hot. Switch off all lights. Turn the accelerator around 5 to 10 mm from its initial position and wait for 2 to 3 seconds then start the engine. I manage to start on 2nd attempt. The free play of the accelerator does not count.

These were what I have discovered so far. But I managed to reach home safely without having a dead engine in the middle of the road.

Weldangrind · 02-26-2015, 11:43 AM

It sounds like you're really getting to know your bike.

SpudRider · 02-26-2015, 12:14 PM

I agree.

FTEY · 02-26-2015, 03:17 PM

Great remedy.. Worked except the shifting to N. Sometimes still cant get it. So i shift down from 2nd gear when i cant get it.

Adventore · 02-26-2015, 09:48 PM

Quote:

Originally Posted by Weldangrind

It sounds like you're really getting to know your bike.

What can I say. I'm a mechanical engineer. Doing research is my daily job. This is also my hobby. When things are getting in your way, you just have to find how to work around the problem until it's permanently solved.

Adventore · 02-26-2015, 09:51 PM

Quote:

Originally Posted by FTEY

Great remedy.. Worked except the shifting to N. Sometimes still cant get it. So i shift down from 2nd gear when i cant get it.

You know? I hate revving the engine at the stop light. Especially when there are young bikers. They will think that you are trying to invite them for a race. But as the matter of fact, I'm just trying to get to my neutral gear.

Weldangrind · 02-26-2015, 10:36 PM

Quote:

Originally Posted by Adventore

What can I say. I'm a mechanical engineer. Doing research is my daily job. This is also my hobby. When things are getting in your way, you just have to find how to work around the problem until it's permanently solved.

That is exactly what I'd be doing, if I could start again.

Adventore · 02-28-2015, 05:46 AM

FTEY and I went for adjustment today. The mechanic uses a short screw driver bit attaching to a socket of ratchet to adjust the PMS. The tuning of our carb is slightly rich. The spark plug is a bit dark. But the adjustment still doesn't solve our problem. We have to send our bike back for him to readjust the carb. Sounds like he will open up the carb and change the pin.

After the adjustment, we put the bike to test by riding over 200km. Although it's not at its best condition, but the ride seems smoother than before. Especially when we ride on a countryside. Slow speed with high gear seems to be very relaxing.

As for the hard to get neutral problem, the mechanic told us that he will change the pin on the clutch. by doing that, shifting to neutral shoul be much easier. But we will have to leave our bike for a day.

02-25-2015, 04:37 PM	#37
thillskier Banned Join Date: Oct 2014 Posts: 223	I use: A flexible screwdriver Its shaft is "wire" and can bend almost 90 degrees, so turn handle horizontal plane, but tip is vertical (or very close to it. You can chang to whatever kind of bit you need also, on the driver end. Very handy. They make a flex bit for drills also, you can use if you have one already. The idea Spud suggested works well also, ie loosen the bands on the manifold, rotate carb, then adjust screw, and rotate carb back to vertical before testing. IT MAY run very rich, if the bowl dumps fuel into intake tract for a minute or so (or be flooded/hard to start for a few minutes). There is a CHANCE the floats on both carbs are too high, and dumping fuel when starting out and or braking or tilting the bike from side to side at a stop. Try that (tilting the bike) and see if it stalls. Thats the way to find out re floats (one way w/o dissaasembly of carb). If its floats, I can explain setting them for you as well. (Spud may have this covered already in his thread...)
	0

02-26-2015, 11:43 AM	#39
Weldangrind Join Date: Mar 2009 Location: Sardis, BC, Canada Posts: 25,977	It sounds like you're really getting to know your bike. __________________ Weldangrind "I figure I'm well-prepared for coping with a bike that comes from the factory with unresolved issues and that rewards the self-reliant owner." - Buccaneer
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02-26-2015, 12:14 PM	#40
SpudRider Join Date: Jul 2008 Location: Idaho Posts: 25,054	I agree. __________________ Spud "Never argue with an idiot. He will drag you down to his level, and beat you with experience." Mark Twain 2015 Zongshen ZS250GY-3 (RX3) 2006 Zongshen ZS200GY-2 (Sierra 200) 2005 Honda XR650L 2004 Honda CRF250X 1998 Kawasaki KDX220 Mods made to my Zongshen ZS200GY-2: http://www.chinariders.net/showthread.php?t=6894
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02-26-2015, 06:04 AM	#38
Adventore Join Date: Feb 2015 Location: Penang, Malaysia Posts: 23	FTEY. My RS3 has been behaving good today. There are a few thing that I have change during my riding. 1) gear shifting behavior. I shift to higher gear after about 1/2 second after engaging the clutch. When shifting to low gear, I will rev the engine before shifting. I just gave a short rev to around 4000 RPM. 2) when engaging to first gear from neutral at stop light. I rev before engaging first gear. 3) engaging neutral. Short revving the engine, it should be easier to get neutral. 4) starting the engine from cold or hot. Switch off all lights. Turn the accelerator around 5 to 10 mm from its initial position and wait for 2 to 3 seconds then start the engine. I manage to start on 2nd attempt. The free play of the accelerator does not count. These were what I have discovered so far. But I managed to reach home safely without having a dead engine in the middle of the road.
	0

02-26-2015, 03:17 PM	#41
FTEY Join Date: Feb 2015 Posts: 48	Great remedy.. Worked except the shifting to N. Sometimes still cant get it. So i shift down from 2nd gear when i cant get it.
	0

02-28-2015, 05:46 AM	#45
Adventore Join Date: Feb 2015 Location: Penang, Malaysia Posts: 23	FTEY and I went for adjustment today. The mechanic uses a short screw driver bit attaching to a socket of ratchet to adjust the PMS. The tuning of our carb is slightly rich. The spark plug is a bit dark. But the adjustment still doesn't solve our problem. We have to send our bike back for him to readjust the carb. Sounds like he will open up the carb and change the pin. After the adjustment, we put the bike to test by riding over 200km. Although it's not at its best condition, but the ride seems smoother than before. Especially when we ride on a countryside. Slow speed with high gear seems to be very relaxing. As for the hard to get neutral problem, the mechanic told us that he will change the pin on the clutch. by doing that, shifting to neutral shoul be much easier. But we will have to leave our bike for a day.
	0