Zongshen Sierra 200GY-2 Countershaft Sprocket Replacement

[SpudRider]

Today I replaced the countershaft sprocket on my Zongshen Sierra 200GY-2 motorcycle. The Zongshen 200GY-2 employs a countershaft very similar to the one used by the Yamaha TW200 motorcycle. Therefore, I decided to use a Yamaha TW200 countershaft sprocket as a replacement. Because of good reports I had read on the Yamaha TW200 forum, I chose to use a PBI 50-733-15 sprocket. In the following photographs the new PBI sprocket is on the left, and my original Zongshen sprocket is on the right. The first photograph shows the “front” of the two sprockets.



The second photograph shows the “rear” of the two sprockets.



You can immediately notice the wear produced on my original sprocket after riding 9,500 miles. However, if you examine the photographs more closely, you will also notice another difference. The two sprockets are almost identical, with one exception. The bolt holes for the sprocket retaining clip are smaller on the PBI sprocket designed for the Yamaha TW200 motorcycle! A quick trip to the hardware store revealed that the Yamaha TW200 sprocket employs two 5x10mm bolts, while the Zongshen 200GY-2 sprocket employs two 6x10mm bolts.

The 5x10mm bolts currently cost $0.13 apiece at Ace Hardware. After buying several bolts, I returned home and installed my new PBI sprocket. Although the bolts are slightly smaller, I had no trouble using the Zongshen sprocket retaining clip.



Besides the 15-tooth sprocket, I also purchased PBI sprockets with fourteen and thirteen teeth. Since I completed my left crankcase cover modification, I can now easily experiment with different sprocket ratios on my Zongshen Sierra 200GY-2. If you wish to learn more about the crankcase cover modification, you might enjoy reading the following thread.

http://chinariders.net/modules.php?n...ewtopic&t=7559

Spud

[forchetto]

Take no notice of Spud. He's just showing off his Crankcase Cover Mod...

[czowner]

I hope "we" are changing the chain and rear sprocker as well, it's not a good practice to change things one at at time. That front sprocket is well worn.

Jonathan.

[TeamCheap]

Yep that stock counter sprocket is shot but I'd be trying to figure out why the excessive wear on just the backside of it.

Something must be misaligned.

[forchetto]

Originally Posted by TeamCheap

I'd be trying to figure out why the excessive wear on just the backside of it.
Something must be misaligned.

I see what you mean. That sort of wear should also produce plenty of metal filings around the sprocket area. I wonder if there were any.
That kind of sprocket fixing (On Hondas at least) is to a certain extent self-aligning, meaning the sprocket is free to move a little bit on the splines even with the bolts done up, so whatever is causing this wear has to be way out of line.

[TeamCheap]

Yeah it is true that the counter shaft sprockets do float a little bit on most everything I have seen.

The wear on the sprocket would indicate the rear sprocket is offset to the left a bit and I'd bet there was some wear on the outer side of the rear sprocket as well but maybe not as noticeable since it is bigger.

Is the engine aligned properly and how is the rear swingarm bushings/bearings, maybe the rear tire is just crooked on the swingarm.

I'm just guessing because something like that should be visually inspected to see what is out of alignment.

Even so if thats all after 9500 miles then thats not to bad I guess.

[FastDoc]

As always, Spud, thanks for taking the extra time to share so others may benefit.

[max_damage]

Hi
Great information Spoud !
Could you please report results of 14 and 13th sprocket driving, iam also interested to change sprockets on my zong (front sprockets), so please,report results, thanks

[AZ200cc]

Nice work Spud, Looks like You uncovered another issue on the procees though.

[SpudRider]

Originally Posted by forchetto

Take no notice of Spud. He's just showing off his Crankcase Cover Mod...

Of course! I will not miss any opportunity to “pimp” my Crankcase Cover Mod! You know me too well, my friend!

Spud

[SpudRider]

Originally Posted by czowner

I hope "we" are changing the chain and rear sprocker as well, it's not a good practice to change things one at at time. That front sprocket is well worn.

Jonathan.

That is an excellent point, Jonathan; I am glad you mentioned it. All motorcycle riders should regularly inspect both drive sprockets. Also, almost without exception, you should replace both drive sprockets as a pair. However, I forgot to mention this important principle because of one distinctive peculiarity regarding my Zongshen Sierra 200GY-2 motorcycle.

I make it a habit to inspect my rear sprocket every time I lubricate my drive chain. Also, every time I change my engine oil I remove my drive chain, immerse, and brush it with kerosene. I then soak the drive chain in the used, warm engine oil before I reattach it to the motorcycle. Before I replace the drive chain I closely inspect the rear sprocket.

Fortunately, my Zongshen Sierra 200GY-2 has an excellent “cush drive” on the rear wheel. After 9,500 miles of use, my rear sprocket appears to be almost as good as new! Below I have posted a recent photo of the inside of my rear sprocket, attached to the cush drive plate.



Here is a recent photo of the outside of the rear sprocket and cush drive plate.



Here is a photo of the inside of the large, robust, rubber absorption block.



Finally, this photo shows the left side of the rear hub, where the “cush drive” mates to the rear wheel.



The “cush drive” on my Zongshen does an excellent job smoothing out the transmission of power to the rear wheel of the motorcycle. As you can see, it also does a superb job preserving the rear sprocket from wear.

However, it is much more difficult to inspect and replace the countershaft sprocket on the Zongshen 200GY-2. Because this motorcycle is patterned after the Yamaha TW200, the entire left crankcase cover must be removed before you can access the countershaft sprocket. Therefore, the almost complete lack of wear on the rear sprocket can be very deceptive. Also, motorcycle riders just beginning to learn how to maintain their bikes might be unaware of an important fact; the countershaft sprocket wears more quickly than the rear sprocket.

Because of this great difference in wear patterns between the two sprockets, I highly encourage all 200GY-2 owners to perform the Zongshen 200GY-2 Crankcase Cover Modification the next time they change their engine oil.

http://chinariders.net/modules.php?n...ewtopic&t=7559

Spud

[SpudRider]

Originally Posted by forchetto

I see what you mean. That sort of wear should also produce plenty of metal filings around the sprocket area. I wonder if there were any.
That kind of sprocket fixing (On Hondas at least) is to a certain extent self-aligning, meaning the sprocket is free to move a little bit on the splines even with the bolts done up, so whatever is causing this wear has to be way out of line.

No, I did not notice any metal filings around the sprocket area. I believe the wear was very gradual over the 9,500 miles traveled. I regularly inspect my Tsubaki 428HQR drive chain; it is in excellent condition.

The countershaft sprocket on my Zong 200GY-2 moves very little when attached to the countershaft by the retaining plate. Also, the quality of metal used to manufacture the original sprocket might not be the best. These factors undoubtedly contributed to the sprocket's wear pattern.

However, my new PBI sprocket is very well made. According to the manufacturer, it is: “Manufactured from Pro quality chromoly steel approaching 200,000 psi yield. Case hardened, finished with electroless nickel plating.” [sic]



Now that I can easily access my countershaft sprocket, I will keep a close watch to see how the PBI sprocket wears in relation to the original, Zong sprocket.

Spud

[SpudRider]

Originally Posted by TeamCheap

…The wear on the sprocket would indicate the rear sprocket is offset to the left a bit and I'd bet there was some wear on the outer side of the rear sprocket as well but maybe not as noticeable since it is bigger…

Good call, TC! Upon closer inspection I have noticed a slight amount of increased wear on the outside of the rear sprocket. However, it is difficult for a novice to notice it, unless he is expressly looking for it.

Originally Posted by TeamCheap

…Is the engine aligned properly and how is the rear swingarm bushings/bearings, maybe the rear tire is just crooked on the swingarm…

I regularly spin the rear wheel, inspecting the drive chain to insure that it travels in a straight, untwisted path. I also inspect the chain slider. Since it was convenient, I replaced both wheel bearings in the rear hub last fall. Both bearings were in very good condition.

Here is a photograph of the drive chain alignment.



Here is a photo of the wear pattern on the top of the chain slider.

Originally Posted by TeamCheap

…I'm just guessing because something like that should be visually inspected to see what is out of alignment.

Even so if thats all after 9500 miles then thats not to bad I guess.

Like many Chinese motorcycles, the Zongshen frame is not perfectly straight. However, I do not notice anything that is terribly out of alignment on the drive train. The engine and rear swingarm are solidly and properly aligned. The rear wheel is not crooked on the swingarm. Perhaps I could use a slightly longer bushing on the left side of the rear axel, and a slightly shorter bushing on the right side? :?:

All in all, I tend to agree with your final assessment; I am not too disappointed with the sprocket wear after 9,500 miles. However, I truly appreciate your thoughtful advice. I certainly intend to keep a close watch on things. I will report back as I notice the wear pattern on my new PBI countersprocket.

Spud

[TeamCheap]

Of course that was 9500 miles with what sounds like excellent chain maintenance other riders results will very.

Good work on maintaining that chain & sprockets.

With the chain off and using a TRUE straight edge of some sort from the rear sprocket to the front sprocket should show any misalignment pretty easily I would think.

I'm wondering if there is some sort of motorcycle laser alignment tool for sprockets.

[SpudRider]

Originally Posted by FastDoc

As always, Spud, thanks for taking the extra time to share so others may benefit.

Originally Posted by max_damage

Hi
Great information Spoud !
Could you please report results of 14 and 13th sprocket driving, iam also interested to change sprockets on my zong (front sprockets), so please,report results, thanks

Originally Posted by AZ200cc

Nice work Spud, Looks like You uncovered another issue on the procees though.

FatDoc, Max, and AZ: Thank you for the kind words. I will certainly report my results regarding the 14-tooth and 13-tooth sprockets.

The weather was beautiful, so I went for a nice long ride yesterday. I am very happy that Spring has finally arrived, and I am also happy to report that the new PBI countersprocket worked great!



As a matter of fact, Max, I think I will install the 14-tooth sprocket today. I will let you know my impressions after a few days of riding.

Spud