2006 ZS250GS

[SpudRider]

Originally Posted by katoranger

I don't know if the cylinder wall would be thick enough for that. I also think that the xt250 is a different case from the tw/xt200 so the cylinder probably wouldn't work.

The ZS250GS cylinder bore is 72.5mm, and the XT250 piston is 74mm in diameter. Therefore, the difference is 1.5mm, which might work. However, I would certainly defer to a machinist's judgement. I think any piston with a diameter of 72.5mm and a wrist pin with the correct diameter to fit the connecting rod will work.

The XT250 engine case is definitely different from the Zong/TW200 engine case. An XT250 cylinder would not fit the ZS250GS crankcase. :(

Spud

[FastDoc]

I thought crap like that only happend to me....

Sorry to hear about your clip. At least you'll get to inspect everything. I remind myself when I make mistakes like this. This is why the pros are pros. I enjoy tinkering but I'd have surely lost my cool over that one.

I like the idea of using Yamaha parts where you can.

We are lucky to have experts here like Spud and Weld.

I'm interested to hear what was causing the problem. Like I said I gave up on mine when I discovered you can't remove the head in situ.

[FastDoc]

Except, the bolt that holds the top sprocket in place for the cam chain was halfway undone, and the threads halfway in were messed up.

If your motor ran, that bolt would have probably have fallen out. If that happened the motor would have been heavily damaged.

[m0t0]

[SpudRider]

That's a common metric bolt, you shouldn't have any problem replacing it at Ace Hardware, et cetera. Please clean up the cam sprocket, and post another photograph of it. If the keyway isn't damaged, the cam sprocket is good, and you merely need to replace the bolt. I would also gently run a thread tap through the camshaft to clean up the internal threads.

The camshaft, bolt, washer, and cam sprocket are all Yamaha parts. However, if necessary, you can get a brand new camshaft from China for about $10.

Spud

[m0t0]

sorry had two pictures of the same bolt. 3 days and still no reply from zongshen america.

[SpudRider]

I'm sorry to say it, but you need to keep contacting Zongshen America. They keep a nice inventory of parts, and the prices are great, but they don't have the best customer service. :roll:

Let's see a photograph of the end of the camshaft where you removed the cam sprocket. I want to see if end of the camshaft has been damaged. Also, please clean up the dirty side of the cam sprocket, and post another photograph of it.

Spud

[m0t0]

spud were you referring to pic a or b? one or two? feel like your at the doc yet? let me know. in the mean time ill soak the sprocket in some gas and see if i cant shine it up. Ill also snap some photos of where the sprocket threads onto.

Also, I have the engine torn down most of the way now but i have hit a roadblock. Anyone know of an easy way to remove the magneto, and also the clutch basket?

Thanks,
M0t0

[SpudRider]

Originally Posted by m0t0

spud were you referring to pic a or b? one or two? feel like your at the doc yet? let me know. in the mean time ill soak the sprocket in some gas and see if i cant shine it up. Ill also snap some photos of where the sprocket threads onto.

Also, I have the engine torn down most of the way now but i have hit a roadblock. Anyone know of an easy way to remove the magneto, and also the clutch basket?

Thanks,
M0t0

Please clean this side of the cam sprocket, and post a photograph. I want to see if the keyway was damaged.



Also, please post a photograph of the end of the camshaft. I want to see if the key, or the fluting on the end of the camshaft is damaged.

To remove the clutch basket you need a clutch holding tool.

http://www.rockymountainatvmc.com/p/...rm=clutch+tool



To remove the flywheel, you need a flywheel holder.



You also need a flywheel puller.



Are you planning to split the crankcase? You don't need to split the crankcase to fix a compression problem. I assume you are pulling the flywheel to replace the cam chain. Why do you want to remove the outer clutch basket? :?:

Spud

[katoranger]

Spud, he thinks that he dropped a wristpin clip in there.

[m0t0]

Originally Posted by katoranger

Spud, he thinks that he dropped a wristpin clip in there.

Nailed it. Plus the farther i get this thing torn down the better i feel about the rebuild. More than one bolt has been loose to the touch at this point.

I have the center bolt removed from the flywheel but wasn't sure if i could use a gear puller to get it out or something else. Ill order up the clutch basket holder. Any recommendations on a flywheel puller?

Thanks,
m0t0

P.S. Spud ill post new pics later today.

Thanks again everyone for all the help.

[katoranger]

I recommend swinging to the nearest dirt bike shop and getting one that fits yamaha 200cc engines. They are not that expensive and usually fit many bikes. I have the one that fits most smaller hondas.

[m0t0]

I'm sorry i should have clarified. Any idea what size i need? If i'm going to order a clutch holder ill just order one of those at the same time. I have nothing against buying local, but most of the shops in town aren't very helpful or friendly. The one shop i normally do business with and trust has kept me waiting for 7 months for some fairing bolts... Apparently they are "on order"

[katoranger]

Spud will know. Whatever fits the yamaha tw200.

Allen

[SpudRider]

Originally Posted by m0t0

...I have the center bolt removed from the flywheel but wasn't sure if i could use a gear puller to get it out or something else. Ill order up the clutch basket holder. Any recommendations on a flywheel puller?

Thanks,
m0t0

P.S. Spud ill post new pics later today.

Thanks again everyone for all the help.

You're welcome. Don't use a gear puller to remove the flywheel; use the correct flywheel puller. The TW200/Zong flywheel puller is not expensive; it's just an M16x1.5, R.H. thread, bolt. My flywheel puller is Motion Pro part #08-0027.

http://www.motionpro.com/motorcycle/partno/08-0027/



You can buy the same flywheel puller, with a different brand name, from a variety of vendors.

Spud