New Zongshen RX3 (ZS250GY-3) Dual Sport

[rjmorel]

In this day and age of superb electronics and FI would one dare to ask if there is a kick starter kit available for the RX3 ? rj

[SpudRider]

Originally Posted by Mudflap

I assume Zongshen has done the testing and concluded these clearances are optimum. The little horizontal Hondas, Lifans, and vertical CG type Lifan and Zongshen 200 lash specs are .05 mm intake and exhaust. In many if not most small motorcycle engines the lash increases as the engine temps go up. The whole engine expands somewhat as it gets hot, not just the valve train.

Thank you for posting that information. I was unaware of the .05 mm intake and exhaust specifications on some of the Chinese engines.

Indeed, I understand the entire engine expands as the engine heats. However, I still believe the exhaust valves must certainly heat up more than the intake valves. The intake valves are cooled by the incoming fuel/air mixture on every intake stroke, whereas the exhaust valves are always heated by the expelled gas on the exhaust stroke.

[SpudRider]

Originally Posted by katflap

this engine parts catalogue for the Megelli Supermoto 250 looks like it could be the same engine.

Engine parts catalogue in English.

http://www.puzey.co.za/Resources/Meg...e%203.28mb.pdf

and here

http://crossfiremotorcycles.com/wp/w...gine-Parts.pdf

** please delete this post if this has already been covered

You are correct. The Megelli Supermoto 250 does employ the same, Zongshen NC250 (ZS177MM) engine as the Zongshen RX3.

[SpudRider]

Originally Posted by rjmorel

In this day and age of superb electronics and FI would one dare to ask if there is a kick starter kit available for the RX3 ? rj

The Zongshen ZS177MM (NC250) engine is installed in several other, Chinese motorcycles. It is also installed in the Gas Gas EC Cami 250, shown below.



Many of these other bikes have a kick starter, so the parts are certainly available. However, the frame of the Zongshen RX3 is different from these other motorcycles, so sufficient clearance for operation of the kick starter might not be present on the RX3. We won't know until after we receive our bikes. If sufficient clearance is present for a kick starter, one would also need to install a different, right crankcase cover, in addition to the kick starter parts.

[SpudRider]

I wonder what the valve lash specifications are for the Gas Gas EC Cami 250, and the AJP PR5?



Both of these bike employ the same, NC250 engine as the Zongshen RX3.

[rjmorel]

Another dirt bike kayo T6 using the nc250 motor, carbureted and elect/kick start.
http://www.icebearmotors.com.au/250c...e-kayo-t6.html

[SpudRider]

The SSR 250R is another Chinese bike which employs the Zongshen NC250 engine. Zongshen only supplies the engine for the SSR SR250R. This engine does have a kick starter.

The SSR SR250R is currently being sold in the United States by at least two online vendors.

http://tboltusa.com/store/ssr-sr250r...ike-p-969.html
http://gokartsusa.com/SSR-250R-5-Spe...loy-Frame.aspx



You can find more photographs of the SSR SR250R at the SSR.com website.

http://ssr250.com/

[culcune]

Asiawing uses the engine in a few of their bikes (but I believe one of these bikes they OEM for SSR)

http://www.asiawing.com/english/DT25...%20COOLED.html

http://www.asiawing.com/english/fox500.html

http://www.asiawing.com/english/xzp250w.html

http://www.asiawing.com/english/nc250.html

[SpudRider]

Originally Posted by culcune

Asiawing uses the engine in a few of their bikes (but I believe one of these bikes they OEM for SSR)

http://www.asiawing.com/english/DT25...%20COOLED.html

http://www.asiawing.com/english/fox500.html

http://www.asiawing.com/english/xzp250w.html

http://www.asiawing.com/english/nc250.html

Thanks for the information, Culcune.

Of the four bikes you listed, it appears the NC250 and DT250W are the two models which employ the Zongshen NC250 engine.

[thillskier]

Spud (or anyone) know if the cam chain adjuster is automatic or manual? Also, what are valve adjustment intervals on the RX-3?
Thats definitely a small valve clearance...about 1/2 what most intake specs are, and almost 1/3 most exhaust valve specs.
This may be a reflection of the better steel used in the valve seats (and valves themselves), which is not wearing as much as in the past. maybe?

[SpudRider]

Originally Posted by thillskier

Spud (or anyone) know if the cam chain adjuster is automatic or manual? Also, what are valve adjustment intervals on the RX-3?
Thats definitely a small valve clearance...about 1/2 what most intake specs are, and almost 1/3 most exhaust valve specs.
This may be a reflection of the better steel used in the valve seats (and valves themselves), which is not wearing as much as in the past. maybe?

The RX3 has an automatic, cam chain tensioner.

Courtesy of MotoJ, the owner's manual for the Zongshen RX3 is available for download from this website.

http://www.chinariders.net/files/Zon...ers_manual.pdf

The links to this manual, the Delphi EFI manual, the CSC maintenance tutorials, and other interesting threads are all included in the Zongshen RX3 sticky thread, which is pinned to the top of this Dual Sport Forum.

http://www.chinariders.net/showthread.php?t=14228

According to Table 2-2, on page 9 of the RX3 owner's manual, the first valve clearance check is scheduled for 1,000 kms (600 miles), and subsequent, valve clearance checks are scheduled every additional 4,000 kms (2,500 miles).

I'm not saying the valve lash specifications are necessarily wrong, but I am very surprised the exhaust valve lash has such a low value.

[Wolftrax]

Originally Posted by SpudRider

According to Table 2-2, on page 9 of the RX3 owner's manual, the first valve clearance check is scheduled for 1,000 kms (600 miles), and subsequent, valve clearance checks are scheduled every additional 4,000 kms (2,500 miles).

I'm not saying the valve lash specifications are necessarily wrong, but I am very surprised the exhaust valve lash has such a low value.

That's a very frequent valve clearence check schedule! KLX 250, CRF250L and WR250R are all between 14000 and 24000 miles. So every time you change the oil you will have to adjust the valves. That's going to be a real PITA.

[SpudRider]

Originally Posted by Wolftrax

That's a very frequent valve clearence check schedule! KLX 250, CRF250L and WR250R are all between 14000 and 24000 miles. So every time you change the oil you will have to adjust the valves. That's going to be a real PITA.

Indeed, that is a frequent schedule. However, I once again think Zongshen is taking a very conservative approach with that maintenance schedule. My Zongshen ZS200GY-2 Owner's Manual specifies the same valve adjustment schedule. However, with over 67,000 miles on that bike's engine, I have not needed to adjust the valve clearances very often. When I do adjust the valves, the adjustment is minor, and the valves hold the adjustment for a very long time.

Once again, I wonder what Gas Gas and AJP are specifying for the valve clearances, and the valve adjustment schedule.

[Wolftrax]

Originally Posted by SpudRider

Indeed, that is a frequent schedule. However, I once again think Zongshen is taking a very conservative approach with that maintenance schedule. My Zongshen ZS200GY-2 Owner's Manual specifies the same valve adjustment schedule. However, with over 67,000 miles on that bike's engine, I have not needed to adjust the valve clearances very often. When I do adjust the valves, the adjustment is minor, and the valves hold the adjustment for a very long time.

Once again, I wonder what Gas Gas and AJP are specifying for the valve clearances, and the valve adjustment schedule.

Just checked the AJP schedule and it's every 3000K(2000mi). I suspect after a few intial early checks it wont be necesarry to check and adjust if the gaps are in tolerance.

[SpudRider]

Originally Posted by Wolftrax

Just checked the AJP schedule and it's every 3000K(2000mi). I suspect after a few intial early checks it wont be necesarry to check and adjust if the gaps are in tolerance.

I agree. One should certainly check the valve lash after the engine breakin. Then, I would check the valve lash again after 2,500 miles. If the valve lash is good, or the adjustment is minor, one can safely extend the inspection schedule. That is the procedure I followed with my Zongshen ZS200GY-2.

Apparently, CSC waited until 8,000 miles to check the valve lash on their red bike which underwent emissions testing. The Silk Road Rider traveled from the east coast of China to Istanbul, and I doubt he checked, let alone adjusted the valve lash during the entire trip.

If I may ask, where did you find the AJP maintenance schedule? Can you please provide a link?