New Zongshen RX3 (ZS250GY-3) Dual Sport

[tikitarik]

Originally Posted by thillskier

The only real complaint and or question re bikes quality perception was the notchy shifting and reluctance to find neutral from first when stopped at a light etc.
This was mentioned in only one or two of the ride reports, and only the first one's I think.

Can you comment on whether this was due to the low mileage on the motorcycles when they were tested? Did the notchiness/hesitation get better or go away with some miles and use over time?
...

A while ago I was able to test ride the blue bike in a parking lot. While neutral did take a little bit to find, it wasn't in any way bad. Hopefully as they wear in it will get better. Regarding shifting in general, it definitely isn't quite as smooth as my crf250l, but it was also much nicer than my friends cb400. I also never had a false shift on it.

And on the note of false neutrals, I had a 1988 Honda VTR250 that always wanted to go into a false neutral between 4-5th and 5-6th. I figured out pretty quickly that all you had to do to fix it was to shift a bit more firmly, and when I switched to Rotella t6 5-40 (probably the best oil I've ever used in my bikes) the problem went away completely.

That bike also had a hard to find neutral that was solved by the synthetic oil.

I'm absolutely sure the RX3 is going to be good.

[Weldangrind]

Originally Posted by SpudRider

Thanks for the clarification. No, I'm not 100% sure regarding the engine displacement. Does the '92 GMC Jimmy employ a 350 cubic inch, SBC engine?

Not from the factory, although several owners have transplanted a 350. I'm almost certain that the '92 had a 4.3l.

[SpudRider]

Originally Posted by Weldangrind

Not from the factory, although several owners have transplanted a 350. I'm almost certain that the '92 had a 4.3l.

I will check with Andy. The engine is a V6, and I'm pretty sure it is stock.

[SpudRider]

I just checked the AJP PR5 Owner's Manual. The last page of the manual, page 25, lists the following specifications for valve clearance.

http://issuu.com/ajpmotos/docs/ajp_pr5_user_manual_en

Intake: 0.05 mm
Exhaust: 0.08 mm

The AJP PR5 employs the same Zongshen NC250 engine, and Delphi EFI as the Zongshen RX3.

[thillskier]

I would (as I commented before) expect the valves to require adjustment more during/immediately after break in than once it has 5000+ iles or so on it. The valve and seat interface will definitely move a bit until te wear surfaces are happy with each othersplacement and interface.
The steel alloys that are used in premium applications work very well and simply wear very little after break in, I've found. (as your experience proves)

I agree re using MOTORCYCLE specific synthetic oils AFTER break in....I'm probably going to run it about 2500 miles before switching over though, just to make sure its completely broken in...

The favorable write ups and knowledge of Zongshens engine building prowess influenced my decision to make this purchsse , you are correct.
They make many engine powered products (like Suzuki, Honda, and Yamaha, ie outboard engines, generators, and much more). Like the Japanese manufacturers, they learned that a good engine design can be used in many formats, like outboards, generators, powertools, motorcycles, etc.

Thanks for the rapid reply and update CSC...

[thillskier]

Spud and Weld, I noticed this site is happily relatively troll and idiot free, compared to most net sites. That does make it much better and easier to have more open discussion...

[SpudRider]

Originally Posted by thillskier

I would (as I commented before) expect the valves to require adjustment more during/immediately after break in than once it has 5000+ iles or so on it. The valve and seat interface will definitely move a bit until te wear surfaces are happy with each othersplacement and interface.
The steel alloys that are used in premium applications work very well and simply wear very little after break in, I've found. (as your experience proves)...

I would check the valve lash before I started my trip across the country. Unless the bike becomes difficult to start, et cetera, you should be able to complete your trip without another valve lash inspection. Upon returning home, I would check the valve lash once again.

[NoVa Rider]

This is a quick introduction from another soon-to-be RX-3 owner. I placed my order with CSC on December 31, actually talked directly to Steve, and I'm really excited about this bike. I love my Honda NT700V but I think the Cyclone should be a great alternative roadster with off-road capability.

Many thanks to Spudrider, Weldangrind, the folks at CSC, and other posters for making this thread so informative and friendly. I'm itching to ride, but its been great fun to read up on the bike while awaiting delivery.

[SpudRider]

Welcome; we are glad you joined us.

[thillskier]

Thanks Spud..Thats kinda what I was thinking I should try to do also (re valve ck before and after the trip. (along with the oil change to the Rotella or Delo diesel zinc fortified motor oil.) I hope to assemble the bike there at CSC, then ride it hopefully a minimum of 50 miles or so, then do an oil change and valve check. I'd also like to open the air box up and maybe derestrict the muffler by removing the middle baffles. That will allow it to breathe a bit better (for better cruise at hwy speed) and still remain quiet . Spark arrestor will not be removed,permanently , however. Its not much of a restriction anyway, and could stop any chance of an off road excursion causing a fire!

Hopefully some of the smarter and more experienced with small EFI bikes can post up instructions re derestricting our bikes so we get the full horsepower that the engines are designed to produce, before stopping them up for USA use. The WR Yamaha gets 4-5 hp (even more in low and midrange power derestricted. Our engines are very similar to the Yamahas I believe..Read that somewhere I think....
Spud, did you derestrict your other Zong? The 200? If so, results?

[thillskier]

My sentiments exactly, NOVA. I am getting quite the list of things needing attention before I start my ride back, however...But thats going to insure I enjoy the trip with less stress and worries for each item off the list!

Doing these things while at CSC where I can avail myself of their knowledge (and any specialty tools that mat be required (like the fuel computer to adjust fueling after I derestrict the intake and exhaust a bit), make good sense to me, and again will let me enjoy the ride with less concern of any issues popping up on the ride back!

[SpudRider]

Originally Posted by thillskier

...Hopefully some of the smarter and more experienced with small EFI bikes can post up instructions re derestricting our bikes so we get the full horsepower that the engines are designed to produce, before stopping them up for USA use. The WR Yamaha gets 4-5 hp (even more in low and midrange power derestricted. Our engines are very similar to the Yamahas I believe..Read that somewhere I think....
Spud, did you derestrict your other Zong? The 200? If so, results?

The Zongshen NC250 engine is not a copy of another engine. I believe Zongshen hired an Italian firm to design the NC250 engine. As far as I know, the NC250 engine is not similar to any Yamaha engine.

I am considering loaning my RX3 to Dobeck Performance in Belgrade, Montana.

http://www.techlusion.com/dobeck-products.asp

Dobeck designs and manufactures the EJK controllers, which maximize engine performance for EFI engines.

I did install a Yamaha exhaust header and FMF silencer on my Zongshen ZS200GY-2. Combined with the correct carburetor jets, the engine definitely produced more power. You can read about this project at the following thread.

http://www.chinariders.net/showthread.php?t=5974

[SpudRider]

Originally Posted by thillskier

...Doing these things while at CSC where I can avail myself of their knowledge (and any specialty tools that mat be required (like the fuel computer to adjust fueling after I derestrict the intake and exhaust a bit), make good sense to me, and again will let me enjoy the ride with less concern of any issues popping up on the ride back!

The Delphi computer is used to diagnose the health of the EFI system. It is not designed to alter the fuel map for the engine control unit (ECU). An aftermarket unit, such as the Dobeck EJK, is needed to alter the fuel map of the ECU. The Dobeck EJK (Electronic Jet Kit) allows you to enrich, or lean the fuel mixture to your preference for idle/cruise, acceleration, and full throttle. Therefore, you can tailor the bike's fuel economy and performance exactly as you wish, and easily change any of these settings at your convenience.

[SpudRider]

Dobeck uses load based technology to program its EJK controllers.

[SpudRider]

Here is a video showing how to install the EJK controller on a Honda CRF250L. The installation would be similar on a Zongshen RX3.