New Zongshen RX3 (ZS250GY-3) Dual Sport

[SpudRider]

Originally Posted by Weldangrind

I didn't ask my question properly. What I meant was, has anybody seen a long filter like that used in a motorcycle engine? If so, what make of bike?

I guess I didn't answer properly. Those photographs I posted are oil filters for motorcycles. I would have to search, but I think the long oil filters are used in some KTM, or BMW motorcycles.

[CSCDude]

Guys:

Joe from CSC here. I write the CSC blog. I've been following this thread with great interest. I'm overseas this week but I'll be back in California next week. Let me know what I can do to help.

[SpudRider]

Welcome to these forums, Joe. We are glad you joined us.

If you are in China, please try to find out what size bearings are used in the lower shock linkage of the RX3. Also, is there in English service manual for the RX3 in digital format? I would love to start studying the service manual.

[SpudRider]

Originally Posted by Weldangrind

Roller rockers are very popular in small block Chev motors, but they fail with catastrophic results.

I checked with Brother Andy, who has over thirty years of professional experience as a diesel mechanic. He says the roller rockers have a good reputation in the big rigs.

[SpudRider]

Originally Posted by Weldangrind

Those sprockets look like CRF parts.

The Honda, CRF C/S sprocket has 21 splines.

http://www.jtsprockets.com/catalogue/model/5161



However, the Zongshen, RX3 C/S sprocket has 13 splines. Therefore, I suspect the RX3 C/S sprocket might be the same as the Suzuki TU250, or GW250.

http://www.jtsprockets.com/catalogue/model/5772

[SpudRider]

It appears the Zognshen RX3 employs the same rear sprocket as the Xinyuan X2, and Xinyuan X5 bikes, as well as some KTM motorcycles.

http://item.taobao.com/item.htm?spm=...06&ns=1#detail

However, we won't know until we can measure one of these sprockets.

[Wolftrax]

Originally Posted by SpudRider

Welcome to these forums, Joe. We are glad you joined us.

If you are in China, please try to find out what size bearings are used in the lower shock linkage of the RX3. Also, is there in English service manual for the RX3 in digital format? I would love to start studying the service manual.

Spud it appears to me your writing the English Service Manual in this thread. Keep it coming!

[Wolftrax]

Originally Posted by CSCDude

Guys:

Joe from CSC here. I write the CSC blog. I've been following this thread with great interest. I'm overseas this week but I'll be back in California next week. Let me know what I can do to help.

Welcome Joe, great to have you on board.

[SpudRider]

The Honda, CRF and XR rear sprokets are nearly identical to many KTM rear sprockets; the only difference is the diameter of the centerline of the bolt holes.

The centerline of the bolt holes for the Honda, CRF and XR rear sprockets has a diameter of 153mm.

http://www.jtsprockets.com/catalogue/sprocket/JTR210



The centerline of the bolt holes for many KTM rear sprockets has a diameter of 150mm.

http://www.jtsprockets.com/catalogue/sprocket/JTR897



I suspect the Zongshen RX3 employs KTM rear sprockets. However, either Honda or KTM rear sprockets will serve well, since they are available with a wide range of teeth. The Honda sprockets basically span 38-53 teeth, and the KTM sprockets basically span 38-52 teeth.

The Minski TRX 300i sold in Russia employs a 13T/37T sprocket combination, since it has a larger, 17-inch rear wheel. The Zongshen RX3 employs a 13T/44T rear sprocket, since it has a 15-inch rear wheel.

If one installs a larger rear wheel on the CSC Cyclone RX3, he will undoubtedly want to switch to a 13T/38T, 14T/40T, 15T/43T, or 16T/46T sprocket combination. Of course, if one switches from the stock sprocket combination, the chain length will also likely change.

[Weldangrind]

Originally Posted by CSCDude

Guys:

Joe from CSC here. I write the CSC blog. I've been following this thread with great interest. I'm overseas this week but I'll be back in California next week. Let me know what I can do to help.

Welcome, Joe!

[Weldangrind]

Originally Posted by SpudRider

I checked with Brother Andy, who has over thirty years of professional experience as a diesel mechanic. He says the roller rockers have a good reputation in the big rigs.

Not exactly apples to apples. Big rig motors don't rev.

[Weldangrind]

Originally Posted by SpudRider

I guess I didn't answer properly. Those photographs I posted are oil filters for motorcycles. I would have to search, but I think the long oil filters are used in some KTM, or BMW motorcycles.

Interesting, since the new Zong resembles the BMW GS bike (to my eye, anyway).

[SpudRider]

Originally Posted by Weldangrind

Not exactly apples to apples. Big rig motors don't rev.

That's true.

[Wolftrax]

Originally Posted by Weldangrind

Not exactly apples to apples. Big rig motors don't rev.

Weren't most of the failures confined to a couple of year runs of the LS7 motor?

[Weldangrind]

Originally Posted by Wolftrax

Weren't most of the failures confined to a couple of year runs of the LS7 motor?

I wasn't singling out a specific LS motor. I've read a few articles in HR and CC that talked about needle bearing failure in afterrmarket roller rockers that are routinely wrung out. Since this bike is gonna be revved consistently, it's worth talking about. I'm glad to hear from Spud that the CRF uses a similar bearing.

My answer would be to periodically change the rockers as a maintenance item, before they grenade. Since the RX3 uses conventional tappets instead of shim and bucket, it would be really easy to swap the rockers, say every 20,000km or so. The only difficulty I can think of would be initially loosening the rocker shafts; it was like they were welded in on my KLR250.

Of course, consistent oil changes are always a good thing, and maybe with proper service, the needle bearings would never fail within the lifetime of the motor. If a needle roller decides to fail, it'll end up in the bottom of the crankcase.