Air filter replacement - Page 2

ob1 · 08-09-2006, 05:28 PM

That filter is way too small for a 200. Check into a Uni pod filter. Too small a filter will make the bike run rich and allow dirt to be pulled through the filter and into the motor.

You can put the pod into your airbox rather easily. On my kids conversion bike, a CR80 frame with an XR80 motor, I took a piece of clear vinyl hose a little smaller than the carb spigot, heated the hose and forced it onto the spigot, then let it cool. Cut a hole in the airbox, stuck the hose in and sealed the hole with black RTV. Mounted the pod on the vinyl hose inside the airbox.

I will have a look at the 2 carbs after I cool off from the day's work, and give my opinion on the jet's compatability.

fratermus · 08-09-2006, 07:26 PM

[quote="ImEazy"]

Quote:

Originally Posted by frostbite

I put together a quick tutorial on rejetting a GY carb if you care to check it out.

http://www.eazys.net/GY200/Carb/carbjets.html

Thanks for the writeup and pics. Very informative for the mechanically retarded like myself.

ob1 · 08-09-2006, 07:55 PM

The pilot, or idle jet appears to be exactly the same between my Lifan Carb and the OE Honda carb [Keihin].

The Lifan carb appears to use what I used to call "flat-top" jets. These look just like a small flat blade screw, only with a hole in the center. Honda used this style jet back in the '70s.

The bowls are slightly different as well. The Keihin bowl is deeper, and the jet is mounted on an extension, I would say this is to keep the jet in the fuel in extreme conditions.

Based on appearances, you could possibly buy the Keihin jet holder and deeper bowl, then convert to late model Keihin jets.

FYI, my Keihin carb is from a '93 XR200.

Here is a good place to shop for jets, after doing your homework

www.sudco.com

dlunt · 08-30-2006, 09:39 PM

I would like to get one of these air filters to replace the stock filter and air box on my Lifan 200GY-5. (Somebody posted this link previously, forgot who)

http://www.motocrossuniversity.com/p...ategory_id=382
or
http://www.motocrossuniversity.com/p...ategory_id=382

I haven't had time to take it apart and measure the outside diameter of the air intake side of the carb. Frankly, I am being lazy, I don't want to have to do it now and again when I get the air filter. :-)

Does anybody know the diameter so that I can order the right one?
Thanks!

ImEazy · 08-31-2006, 12:03 AM

dlunt - I'm pretty sure it was 39mm the carb is 28mm.
I just went to the garage and looked at the 30mm carb
I have and the filter was 42mm. Hope this helps...

When I bought the filter for the 30mm carb I measured
for it wrong and ended up with a 48mm filter that I won't
use. If anyone wants it or has use for it? I'll send it to
you for shipping. Just let me know.

dlunt · 09-04-2006, 11:42 AM

Thanks ImEazy
I had time yesterday to pull stuff apart and verify.
42 millimeters = 1.65 inches
I measured just under 1.75 inches for the outside diameter.
You were on the money size wise.

It also looked like the 6' one would fit easily in the space.
So I orderd on of the 1 3/4" X 6" UNI Flex Core Sock Filters.
http://shop.thumpertalk.com/catalogs...ault.asp?p=512

I left the cover off of my current air filter box. Now I have a little bit of a stutter in the powerband. I imagine once I get the free flowing UNI pod on there that I am going to have to fiddle with the mixture setting a little until I get it right.

ImEazy · 09-05-2006, 01:46 AM

Quote:

Originally Posted by dlunt

Thanks ImEazy
I had time yesterday to pull stuff apart and verify.
42 millimeters = 1.65 inches
I measured just under 1.75 inches for the outside diameter.
You were on the money size wise.

Glad I could help. Yours must have come with a 30mm carb then. Mine came with a 28mm.

RD · 09-10-2006, 04:53 PM

Anyone know where I can find a smaller main jet for the LF200 GY-5? I live and ride at 9000 feet elevation. Thanks, ZZ

RD · 09-10-2006, 07:37 PM

OK: I found what I was looking for...carb main jets.

For my altitude (9000 ft.) and the nominal air temperature we typically ride in, I've ordered some smaller main jets for my daughter's bike. The stock jet in my LF200 GY-5 was a 98. I'll calculate that I'll need either an 88 or 92. Ordered both and a couple more sizes from ww.sudco.com (minimum order is 4 jets).

The carb main jet is from a Keihin Carb. Use 99101-393-xxx for Honda VB, VD and VE series carbs: 6mm round head diameter and 8mm overall length.

Good luck and hope this helps.

PS I also dropped (leaned) my needle one notch. I'm assuming that helps although I did not notice any part throttle (< WOT) problems. I thought I would also order a smaller pilot jet but could not find the type of jet. Since I've not had part throttle issues, I'll probably jet focus on the main jet for now.

dlunt · 09-11-2006, 07:30 AM

Installed new Uni Flex Core Sock air filter on Lifan GY-5. 6" one. Fits good.
http://shop.thumpertalk.com/catalogs...ault.asp?p=512
I can definitly feel a good difference when I roll into the throttle. Top of the rpm's breathes much better.

But if I do full hard twist of the throttle it just pauses before it goes.
I think I need to do the c-clip in the carb down one more setting.

If that doesen't do it then I was wondering if there is there a carb adjustment screw somewhere? I know which one is the idle adjustment.
But I noticed a knurled and slotted screw at the front bottom of the carb.
It has an ink mark like you usually see on carbs that can be adjusted.

Or is there a cover that needs removed to get to an adjustment screw?
A couple of my Jap bikes had these, but I never had to touch them.

amc31b · 10-03-2006, 05:25 AM

dlunt,
Seems like you have a good plan here. I am interested in doing the same thing to my new 2006 roketa RKM-E5. It kinda seems like a hassle though, especially seeing as I just got it running perfrectly. 93 octane gas and some adjustment with the idle screw worked the kinks out. Let me know how changing the air filter works for you and i'll probably do the same to my E5.

dlunt · 10-03-2006, 03:21 PM

It is some work and trial and error. I really like the acceleration improvement.
See this thread:
http://www.chinariders.net/modules.p...iewtopic&t=380

To add to that I have actually backed out the fuel screw almost 2 turns from the stock setting. I think larger jets would help even more. I am waiting for someone to successfully do this, then maybe I will give it a try next summer.

omega_man · 01-04-2007, 10:52 PM

where'd imeazy get that air filter?

where do I get one?

08-30-2006, 09:39 PM	#19
dlunt Join Date: May 2006 Location: Camby, Indiana Posts: 494	I would like to get one of these air filters to replace the stock filter and air box on my Lifan 200GY-5. (Somebody posted this link previously, forgot who) http://www.motocrossuniversity.com/p...ategory_id=382 or http://www.motocrossuniversity.com/p...ategory_id=382 I haven't had time to take it apart and measure the outside diameter of the air intake side of the carb. Frankly, I am being lazy, I don't want to have to do it now and again when I get the air filter. :-) Does anybody know the diameter so that I can order the right one? Thanks! __________________ 2006 Flywing(Jianshe)100 2002 Suzuki DR650
	0

08-31-2006, 12:03 AM	#20
ImEazy Join Date: Jun 2006 Location: N.E. Ohio (Near Akron) Posts: 599	dlunt - I'm pretty sure it was 39mm the carb is 28mm. I just went to the garage and looked at the 30mm carb I have and the filter was 42mm. Hope this helps... When I bought the filter for the 30mm carb I measured for it wrong and ended up with a 48mm filter that I won't use. If anyone wants it or has use for it? I'll send it to you for shipping. Just let me know. __________________ 2000 MZ Baghira
	0

09-04-2006, 11:42 AM	#21
dlunt Join Date: May 2006 Location: Camby, Indiana Posts: 494	Thanks ImEazy I had time yesterday to pull stuff apart and verify. 42 millimeters = 1.65 inches I measured just under 1.75 inches for the outside diameter. You were on the money size wise. It also looked like the 6' one would fit easily in the space. So I orderd on of the 1 3/4" X 6" UNI Flex Core Sock Filters. http://shop.thumpertalk.com/catalogs...ault.asp?p=512 I left the cover off of my current air filter box. Now I have a little bit of a stutter in the powerband. I imagine once I get the free flowing UNI pod on there that I am going to have to fiddle with the mixture setting a little until I get it right. __________________ 2006 Flywing(Jianshe)100 2002 Suzuki DR650
	0

09-10-2006, 04:53 PM	#23
RD Join Date: Sep 2006 Posts: 18	LeFan 200cc carb jetting Anyone know where I can find a smaller main jet for the LF200 GY-5? I live and ride at 9000 feet elevation. Thanks, ZZ
	0

09-10-2006, 07:37 PM	#24
RD Join Date: Sep 2006 Posts: 18	LF200 GY-5 carb jetting for altitude OK: I found what I was looking for...carb main jets. For my altitude (9000 ft.) and the nominal air temperature we typically ride in, I've ordered some smaller main jets for my daughter's bike. The stock jet in my LF200 GY-5 was a 98. I'll calculate that I'll need either an 88 or 92. Ordered both and a couple more sizes from ww.sudco.com (minimum order is 4 jets). The carb main jet is from a Keihin Carb. Use 99101-393-xxx for Honda VB, VD and VE series carbs: 6mm round head diameter and 8mm overall length. Good luck and hope this helps. PS I also dropped (leaned) my needle one notch. I'm assuming that helps although I did not notice any part throttle (< WOT) problems. I thought I would also order a smaller pilot jet but could not find the type of jet. Since I've not had part throttle issues, I'll probably jet focus on the main jet for now.
	0

08-09-2006, 05:28 PM	#16
ob1 Join Date: Jul 2006 Posts: 499	That filter is way too small for a 200. Check into a Uni pod filter. Too small a filter will make the bike run rich and allow dirt to be pulled through the filter and into the motor. You can put the pod into your airbox rather easily. On my kids conversion bike, a CR80 frame with an XR80 motor, I took a piece of clear vinyl hose a little smaller than the carb spigot, heated the hose and forced it onto the spigot, then let it cool. Cut a hole in the airbox, stuck the hose in and sealed the hole with black RTV. Mounted the pod on the vinyl hose inside the airbox. I will have a look at the 2 carbs after I cool off from the day's work, and give my opinion on the jet's compatability.
	0

08-09-2006, 07:55 PM	#18
ob1 Join Date: Jul 2006 Posts: 499	The pilot, or idle jet appears to be exactly the same between my Lifan Carb and the OE Honda carb [Keihin]. The Lifan carb appears to use what I used to call "flat-top" jets. These look just like a small flat blade screw, only with a hole in the center. Honda used this style jet back in the '70s. The bowls are slightly different as well. The Keihin bowl is deeper, and the jet is mounted on an extension, I would say this is to keep the jet in the fuel in extreme conditions. Based on appearances, you could possibly buy the Keihin jet holder and deeper bowl, then convert to late model Keihin jets. FYI, my Keihin carb is from a '93 XR200. Here is a good place to shop for jets, after doing your homework www.sudco.com
	0

09-11-2006, 07:30 AM	#25
dlunt Join Date: May 2006 Location: Camby, Indiana Posts: 494	Installed new Uni Flex Core Sock air filter on Lifan GY-5. 6" one. Fits good. http://shop.thumpertalk.com/catalogs...ault.asp?p=512 I can definitly feel a good difference when I roll into the throttle. Top of the rpm's breathes much better. But if I do full hard twist of the throttle it just pauses before it goes. I think I need to do the c-clip in the carb down one more setting. If that doesen't do it then I was wondering if there is there a carb adjustment screw somewhere? I know which one is the idle adjustment. But I noticed a knurled and slotted screw at the front bottom of the carb. It has an ink mark like you usually see on carbs that can be adjusted. Or is there a cover that needs removed to get to an adjustment screw? A couple of my Jap bikes had these, but I never had to touch them. __________________ 2006 Flywing(Jianshe)100 2002 Suzuki DR650
	0

10-03-2006, 05:25 AM	#26
amc31b Join Date: Oct 2006 Location: Ft Bragg, NC Posts: 37	dlunt, Seems like you have a good plan here. I am interested in doing the same thing to my new 2006 roketa RKM-E5. It kinda seems like a hassle though, especially seeing as I just got it running perfrectly. 93 octane gas and some adjustment with the idle screw worked the kinks out. Let me know how changing the air filter works for you and i'll probably do the same to my E5.
	0

10-03-2006, 03:21 PM	#27
dlunt Join Date: May 2006 Location: Camby, Indiana Posts: 494	It is some work and trial and error. I really like the acceleration improvement. See this thread: http://www.chinariders.net/modules.p...iewtopic&t=380 To add to that I have actually backed out the fuel screw almost 2 turns from the stock setting. I think larger jets would help even more. I am waiting for someone to successfully do this, then maybe I will give it a try next summer. __________________ 2006 Flywing(Jianshe)100 2002 Suzuki DR650
	0

01-04-2007, 10:52 PM	#28
omega_man Join Date: Jul 2006 Posts: 39	where'd imeazy get that air filter? where do I get one?
	0