BIg Problem with my Zong.

[SgtRope]

Hi Guys

While driving back from work full throttle my bike gave a few jerks/pulls like i was running out of gas and lost all power until i came to a full stop. i waited 2 minutes and start the bike and drove off. upon arrival i noticed some oil on the engine.
/
ant ideas what happened?

:thanks:

[Wild_Alaskan]

hard to say, where is the oil on your engine and what is the current oil level? sounds like possibly water in the gas or too little piston ring gap causing a minor heat seizure. stators can do things like that but usually wont start back up right away.

[Weldangrind]

After you got it started again, how did it run? How long did you ride from that point?

[FastDoc]

How sure are you there was no oil on the engine before the event? Is it related? Where is the oil?

[SgtRope]

once it completely lost power and i pulled over i waited for about 2min started it back up
and still had little jerks as i went along.

i am not to sure about the oil , there was no oil about 3 days ago.

i also think it might be heat related and it might be the piston problem.

what would the next step be in fixing the problem if its that at all.

just took it for a drive now and all was running fine , the jerks normally starts when i have been driving for 20km at full speed.

the oil is at the left hand side at the bottom. my chain is also full of oil.

[FastDoc]

I bet the oil is not related to your problem.

What is the oil level? Low or maybe overfilled?

I'd be thinking fuel. Some dirt or water in there. Also a non-venting fuel cap can cause symptoms like this. Running too lean at high speed can cause overheating. Examine the plug. If you don't know what to look for take pics and share them here we will help you.

[SgtRope]

Hi FastDoc

oil might be slightly over filled. and yes i dont have a venting fuel tank . what do you mean running to lean at high speeds? just changed the oil , spark plugg , cleanded the oil filter and airfilter.

i think i might have had i slight engine seizure/overheat.

how can i fix this or prefent?

thx

[FastDoc]

If the carb is jetted lean, and I THINK Zongs are typically not (even with an aftermarket exhaust, will have to wait for Spud), it can make the engine overheat.

Lets see a pic of your p;lug. Do you know how to do a 'plug chop'?

[FastDoc]

http://www.dansmc.com/sparkplugs1.htm

[SgtRope]

well i am glad the the engine didn't totally seized to the point where it dont want to turn anymore.

i will have to slow down a bit until i know what to do.

[FastDoc]

Read Dan's article and post a pic of the plug.

[SgtRope]

i just changed the spark plugg 5 days ago and it was light in clour and not black and rooty. will take out the new one tomorrow at work and post a picture.

[SgtRope]

sorry for my noob reply. just finished reading the whole post and understand now.
will have a look tomorrow and post a picture.

Thanks

[FastDoc]

No worries. This may not be the problem but it is the right place to start looking.

Spud and Weld and Kato will be able to contribute more also :-)

[Wild_Alaskan]

next time it happens try and loosen the gas cap (if you can safely do so at full thottle) and see if the sputter goes away. I think doc is on to something with the tank venting issue these bikes sometimes have. Also a clogged fuel valve (at the tank or within the carb) can result in that same issues, although i have only ever had this problem when using the ultra low quality gas in alaska.

[SpudRider]

If you don't have water in your fuel, or varnish in your carburetor's jets, I suspect a failing CDI unit. ;) Based upon my experience with this motorcycle, I doubt the gas tank has venting problems, but it's possible.

I strongly suggest you get a spare CDI unit as quickly as possible, even if this problem is determined to be fuel related. All the Chinese CDI units are prone to failure, and your Zong is not exempt from this generality. ;) A spare CDI unit greatly facilitates troubleshooting problems such as this. In addition, when, not if, your CDI unit fails, you can install the spare CDI unit and keep riding. Otherwise, you will be unable to ride the bike until the very slow boat arrives from China. :ohno:

[Weldangrind]

I hope we are not giving you too many answers, but I think it's a crankcase ventilation problem. There is a large black hose underneath the carburetor, and it probably routes behind the engine and points at the ground. If it is clogged, pressure in the crankcase will push oil out somewhere else, just as you observed. Make sure the hose is clear, and make sure it is not kinked.

[SgtRope]

Ok so today i did about 100km(62miles) keeping the average speed to about 100kph/60mph , not full throttle like yesterday which caused the seizing/overheating.

I also checked the spark plug ( picture belowe). and where simular to one of these which might suggest to lean.

Also there is no vent in my Fuel tank.
And my chain looks a bit on the loose side? and as you can see there is some oil on the rear Tyre and rim.

Then the last picture shows where the oil is coming out . also its only coming out of the left side not the right.

[katoranger]

Does it hop like a kangaroo?

[SgtRope]

haha no!!

[Weldangrind]

Your fuel cap has a vent built in.

[Wild_Alaskan]

too lean can indicate lack of fuel in the carb, such as the float height being too low from lack of fuel flow, Or being to lean because of jetting causes excessive heat which can lead to heat seizures, I would still bank on a fuel flow problem. get a new cdi as spud suggested, they are a cheap way to narrow problems down on these bikes

[Wild_Alaskan]

also unless you are going for all out gas mileage, shoot for a tan-brown color on the spark plug, that typically where you make the most power as well.

[SpudRider]

Based upon my experience I doubt either the crankcase vent or the fuel tank vent are causing problems. However, both are easy to check, and can be easily verified, or eliminated as problems. :)

As WA suggested, the next time you have the problem, open the fuel cap and see if you hear a sucking sound, or notice a vacuum. Then note if the problem disappears.

The crankcase vents into the air box, and rarely, if ever gets clogged. However, you can easily examine the crankcase vent tube by removing it from the crankcase and the air box, and examining it for obstructions.

I also doubt the engine as seized. The Zong's carburetor is jetted properly for sea level, and is invariably rich at higher altitudes. Also, the engine is manufactured to very high standards. I have never heard of a Zong or TW200 engine seizing from a too lean fuel mixture.

I strongly suggest you do yourself a big favor, and get a spare CDI unit as quickly as possible. ;) CDI failures are intermittent for a while before the CDI unit fails completely. You really shouldn't be riding now without a spare CDI unit, as you are very likely to get stranded, usually in a bad place at a bad time. :wtf: Also, you need a spare CDI unit to troubleshoot possible electrical problems such as this. ;)

As I stated earlier, I would also check to see if the carburetor and jets are gummy with varnish. However, I strongly suspect the CDI unit has failed. You are experiencing classic symptoms pointing to a faulty CDI unit. ;)

[SpudRider]

I suspect your drive chain might be oiled too much. However, you do need to verify the location of any possible oil leak from the engine. ;) Spray the suspected areas of the engine with brake cleaner. Then wash the bike to remove the grime. Once the engine is clean, keep examining the suspected areas to see if oil is indeed leaking from the engine.

Also, I suggest you clean the rear wheel and the drive chain. You can use WD40, diesel fuel, et cetera. Then apply chain wax, 90W gear oil, or any other clear lubricant. If you don't see oil coming from the engine, and the oil disappears from the rear wheel, you can verify whether the drive chain was oiled too much. ;)

[edtardo]

I don't know if this will help, but I was having a similar problem. I checked everything I could think of, turned out that the connector on the wires coming out of the engine had melted and was shorting out.

[Weldangrind]

Ed, that's awesome! I hadn't even thought of electrical trouble.

[SpudRider]

Indeed, that's a good suggestion, Ed. :tup: The wires from the stator and pickup coil exit the left crankcase cover near the clutch lever arm on the left side of the engine. One should make sure they are not pinched, or damaged in any way.

I doubt either the stator or pickup coil are damaged on a bike with so few miles on the odometer. I strongly suspect either a gummy carburetor, or a bad CDI unit. In either event, one really needs a spare CDI unit for his Zong, or any Chinese motorcycle for that matter. ;)

[SgtRope]

Hi Guys

Ok so my previous post i talked about my bike giving little jerks and pulls when riding for a while . so this moring i completely stripped down my bike to look at everything.

few things i noticed .

1.crankcase cover botls where loose so might explane the oil leak.
2. completely removed my fuel tank , drained it to look for rust etc. (clean)
3. the carb hose that ran from the carb to my air filter was completely loose which could explain a few of my problemes.

4. Also adjusted my PCM screw on my carb to 3.1/2 from 3. 3/4.
5. the oil filter is stainless steel so it can be rinsed if you want to clean it.

i have check everthing , no loose wires , bent or kinked hoses.

so if my bike still cuts out or give these little jerks i will have to replace the CDI unit.

thks for all the help

[SpudRider]

You're making good progress. :tup:

[katoranger]

Like Spud has said. Buy a spare CDI.

[FastDoc]

Any update or resolution?

[SgtRope]

HI FastDoc

well i noticed a bit less power since the loose hose from the carb to the airfilter was connected. which make sense. i rode home after work today and had no jerks/pulls but will chk Wednesday again and let you know.

so the only thing thats left will be a new cdi unit.

will keep you posted and thx for all the helpful tips and ideas.

[SpudRider]

On your Zong the 'hose' from the air box to the intake of the carburetor is actually made of plastic. :ohno: If you have time, I highly recommend removing the stock 'hose,' and replacing it with the very nice, rubber hose for the Yamaha TW200, which is part #6 in the following diagram. :tup:

http://images.powersportsnetwork.com/fiche/images/YAMAHA/2006/Motorcycles/190729_INTAKE.gif

I made this switch on my Zong, and it is one of the best modifications I have made to my bike. :) Removing and re-installing the carburetor is now much easier. :tup: Also, I get a better seal between the air box and the carburetor. It's important to get a good seal to prevent dust from entering the cylinder along with the air/fuel mixture. The dust will promote intake valve recession into the valve seat. :ohno:

[SgtRope]

i think mine is already rubber. but will make sure tomorrow.!

[SpudRider]

i think mine is already rubber. but will make sure tomorrow.!

I also thought it was rubber, but you will know it is plastic if you ever try to remove or install the carburetor when it is cold. ;) If you compare your carburetor 'hose' to the carburetor hose on a Japanese motorcycle, you will quickly see the difference.

This modification is not something you need to do immediately. However, this modification is inexpensive, and very easy to perform. :) I suggest you purchase the TW200 carburetor hose, and wait until the next time you need to remove the carburetor. I can promise you will never regret you switched to the rubber, TW200 carburetor hose. :tup:

[SgtRope]

Hi SPud

Just checked the hoses , they are in fact rubber. Someone before me must have changed them.
Will check with my local bike mechanic for a spare CDI unit.

[SpudRider]

That's good. :tup: I see Zongshen South Africa is still in business, so they might be able to get you a spare CDI unit. :)

http://www.zongshen.co.za/index.html

I also found this advertisement for a new CDI unit. ;)

http://www.bidorbuy.co.za/item/81073147/Zongshen_ZS_200_GY_2_cdi_ignitor_igniter_ecu_unit_ new_scarce.html

http://images.bidorbuy.co.za/user_images/051/308051/308051_120607203031_2012-06-07_20.23.02.jpg

If all else fails, you can certainly get a CDI unit from the Chinese Taobao website. :)

http://gd4.alicdn.com/bao/uploaded/i4/T1iQRYXeXnXXa3__E1_042456.jpg_460x460.jpg_.webp

http://item.taobao.com/item.htm?spm=a230r.1.14.142.RO8EUE&id=9093511749

[SgtRope]

wow thanks Spud.

i will have a look.

[Weldangrind]

Depending upon how the bike was stored before you bought it, you might need to replace the airbox boot anyway. I have a TW200, and it had a shrunken airbox boot that had become very hard. A new boot was noticeably longer and much softer, making installation very easy, as Spud says.

[Pliskin]

I am amazed that you can do 100 kmh. :hmm:

Also how much oil do you put in? Yes your chain appears to be loose. Best way to find out, is tighten it one notch and feel the difference in shifting. It should be easier. If there is a noise or vibration coming from the front sprocket it is too tight.

[SpudRider]

I am amazed that you can do 100 kmh. :hmm:

Also how much oil do you put in? Yes your chain appears to be loose. Best way to find out, is tighten it one notch and feel the difference in shifting. It should be easier. If there is a noise or vibration coming from the front sprocket it is too tight.

My Zong is geared for the trail, yet it will easily cruise at 100 kph/62 mph. :hmm:

[SgtRope]

Hi Guys

Ok so it seems the jerkking/pulls came from a loose carb to airfilter hose, which kinda make sense and correct me if i ma wrong. Since the engine is aircooled it will need more air the hotter and the faster i drive , so after 15min full throttle the engine gets hot and more air is needed but because of the loose air hose it sucked in to much air and the air to fuel ratio became to lean and caused the overheating /siezers.

i easly get 110kph (68mph) and more did 125kph(77mph) this morning.
the bike dont use to much oil and takes about 1.4liters to full.

[SpudRider]

A loose or cracked carburetor hose will introduce more air and create a lean fuel/air mixture. I hope you resolved your problem. :)

However, a CDI unit will fail intermittently before if fails completely, and the problems are first noticed when the bike is hot. Don't hesitate to get at least one, spare CDI unit as quickly as our can. ;)

[SgtRope]

Hi Spud

yes its solved and it was because of the loose hose.

thx a mil.

[SgtRope]

just replaced the stock break fluid, was brown and muckey. makes i big diffrence, smooth.

[SgtRope]

Also when i did my oil change just to make sure that my piston etc was getting oil i check and openend this screw. luckily i was getting good oil flow.:) Thanks Spud:thanks:
all these tips and hints help us Noobs to track/ narrow down the problems.
this must be one of the best sites to learn and teach yourself to maintain you bike without breaking the bank.
compliments to spud for the picture.

[SpudRider]

You're welcome. :)

[Pliskin]

My Zong is geared for the trail, yet it will easily cruise at 100 kph/62 mph.:hmm:
Mine won't do it. Even at 80kmh (49mph) the engine is screaming. :shrug:

http://imagizer.imageshack.us/v2/800x600q90/836/585v.jpg (https://imageshack.com/i/n8585vj)
The above chart represents my shift points as per tw200 manual recommendation.

http://www.youtube.com/watch?v=0qeukFPVqt0#t=123
You guys must be riding like this. His engine is modified i think.

the bike dont use to much oil and takes about 1.4liters to full.
http://imagizer.imageshack.us/v2/800x600q90/690/rlhk.jpg (https://imageshack.com/i/j6rlhkj)
I would recommend 1 litre. ;)


just replaced the stock break fluid, was brown and muckey. makes i big diffrence, smooth.
Fill it so it's just above the low line mark.

this must be one of the best sites to learn and teach yourself to maintain you bike without breaking the bank.
compliments to spud for the picture. Spud is the man. :)

[SgtRope]

Spud is indeed the man..!!

[Weldangrind]

It sounds like he broke his TW at the end of that vid.

My TW will easily move beyond 60mph / 100km/h, but I haven't pushed it with the old worn top end. I'll be rebuilding the motor in a few weeks, and I'll do some test runs once it's broken in properly.

[SpudRider]

What sprocket combination are you using, and how many kilometers have you ridden, Pliskin? :hmm:

[FastDoc]

You all may recall I had a mid 80's TW for a few years. I bought it for my ex to learn how to ride on.

It would pull 60+ easily enough, but revved high.

Spuds Zong will run 60 pretty easily, even on a modest hill or into a small headwind, without having to tuck.

[Wild_Alaskan]

looked at the video and thought that is was total BS. then i read the description and apparently it has a webcam cam in it among other mods. didn't think there were aftermarket cams for something like a TW

[Pliskin]

I'll be rebuilding the motor in a few weeks, and I'll do some test runs once it's broken in properly.Good luck with the rebuild Weld.

What sprocket combination are you using, and how many kilometers have you ridden, Pliskin? :hmm:
Spud, I've got 16/46 combo. It improved the cruising speed by 5-10km/h (3-6mph). Just under 29.000km (18,000 miles) trouble free i might add. :tup: Maybe it's jetted for good fuel consumption. Fuel consumption around 2.6 - 2.8 litre per 100km. (84-90 miles per gallon if i did the conversion correctly) Maybe the jets need to be bigger. I can see now that it is possible to go faster. I might look into it one day. Thanks for the insight.

[SpudRider]

...Spud, I've got 16/46 combo. It improved the cruising speed by 5-10km/h (3-6mph). Just under 29.000km (18,000 miles) trouble free i might add. :tup: Maybe it's jetted for good fuel consumption. Fuel consumption around 2.6 - 2.8 litre per 100km. (84-90 miles per gallon if i did the conversion correctly) Maybe the jets need to be bigger. I can see now that it is possible to go faster. I might look into it one day. Thanks for the insight.

:hmm:

If you are using the stock carburetor jets, your bike is very close to an optimum fuel mixture at your elevation. How often do you clean the air filter? How often do you check the valve clearances? Are the valve clearances holding?

[Pliskin]

Once i took it to a mechanic long time ago to make it go faster. He did make it idle better but couldn't improve on speed. I never asked him if he changed anything but don't think he did. The bike runs basically the same like it was from the first day.

Valve clearance i check every 5.000km (around 3000miles). Next one I'll do in 1000km. They were within the spec last time. I cleaned the air filter last September. The air filter is never that dirty doesn't matter how long i don't clean it. ;)

[FastDoc]

Is your filter oiled?

[Pliskin]

Yes it is.

[zingshoen]

Sgt.Rope, when you wrote your zong does 125 km/h, i do imagine you would have read that figure on your speedo? that speedo isn t very accurate with the 18 inch front wheel, as it is meant for a 21 inch front wheel.

100 km/h (looks like 115 on the speedo with the 18 inch) are doable, but past 80 the little motor revs high and the bike vibrates with that, so it is not that much fun if you have to keep it up.

[SgtRope]

Hi Zingshoen

yes i think i might have mistaken , i drive it at 115kph on the highway and i do so for about 40km to work and 40km back everyday. This bike is rock solid and handles the long distances very well.

[zingshoen]

yeah, i understand, i love the zong, but you seemed to be very fast. i m thinking of replacing the speedo with one that works for the 18 inch wheel sometime.