Valve adjustment (ventiljustering) QM200GY

[CathastrophiX]

Adjusted the valves on my QM200GY today. You don´t have to remove the tank or plastics to do this, (it´s fiddly but doable).
You need:
17 mm ring spanner (ringnyckel)
10 mm ring spanner
Screwdriver bit
10 mm Allen wrench (insexnyckel)
17 mm socket (hylsa)
0,10 and 0,15 mm measure blades? (bladmått)

Remove the two valve inspection caps on the top of the engine (17 mm)
Remove the chrome inspection bolt on top of the left crank case (17 mm).
Remove the allen cap (10 mm) in the center of the left crank case.
Use the 17 mm socket to turn the engine over until the mark on the fly wheel (svänghjul) matches the TDC (övre dödpunkt) mark on the crankcase. (Make sure you´re on the right stroke).

Then you can adjust your valves to these clearances:
IN (Insug) 0,10 mm
EX (Avgas) 0,15 mm
(Yes, I know it´s more than on Lifan type engines, but those are the correct numbers)

The jamb nut is 10 mm, use the screwdriver bit to turn the pin.

If your hands are too big, it´s easier if you remove the right tank plastic (3 philips screws), the gas wire from the carburettor and the rubber hose (that goes from the "EGR" valve to the air box) from the air box.

[ob1]

Tip-O-The-Week;

Make sure to check for any dirt or debris that could fall into the head BEFORE you begin, and clean as necessary. You can easily knock the dirt loose while working, and...

[CathastrophiX]

Yes... and make sure you make adjustments with COLD engine...

[tzrider]

Ain't gonna calculate it, but in inches, I set mine at .002" intake, .004" exhaust. This is Honda spec. Seems happy with that. Mine is an OHC motor. I suspect the OHV motors might have a little more clearance considering more valve train that is expanding with heat, but I don't have a manual for either design. I have been working out of XR manuals for specs.

[CathastrophiX]

Originally Posted by tzrider

Ain't gonna calculate it, but in inches, I set mine at .002" intake, .004" exhaust.

That equals IN 0,05 and EX 0,10 mm.

Factory settings for the QM200GY is IN 0,05 and EX 0,08, but then there´s risk of burnt valves, so recommended clearance is IN 0,10 (0,004") and EX 0,15 (0,006")

The engine is an OHC engine. Looks identical to the Suzuki DR200 engine.
Does anyone know the valve specs for the Suzuki?

[tzrider]

Good info. Break in is the most important period that the valves should be set up loose for. Valves will seat in during this period. After break in, they tend to get loose. I'll set 'em a little looser next time and see how bad it rattles. Can't be any worse than that old XL600R with the RFVC head and all those levers slappin' around in there. That thing sounded like it was going to come apart any minute, but of course, it never did.

[forchetto]

Although very happy with my Qingqi-Qlink QM200GY super motard so far, I was never comfortable with the abscence of valve clearance check and/or adjustment in the makers handbook maintenance schedule.

The Spanish importer tells me it's not required, EVER. Having ridden and maintained bikes and cars for over 30 years I know this is pure bullshit, but finally managed to get the settings out of him.

They told me 0.5 inlet and 0.8 exhaust. When I laughed at the ridiculously large clearances for a Japanese-derived bike engine, the service manager went quiet, consulted some papers and came up with the more reasonable 0.05 and 0.08. This, I reluctantly accepted.

As I am unable to locate a workshop manual for the Qingqi I bought one for its nearest equivalent, the Suzuki DR200SE and learned there that Suzuki's clearances for both inlet and exhaust are 0.08 to 0.13 mm.

Thinking this was strange I searched through many forums, in several languages and using the various names Qingqis are sold as in different countries.

I came across Catastrophyx advice, backed by Qingqi Sweden, concerning the problem with burned valves and advice to set them at inlet 0.10 and exhaust 0.15 mm.
Like all information that could be useful for future reference I copied the messages to my desktop and forgot about it.

From 500 km onwards the bike started dying out ocassionally on stopping for traffic lights, junctions, etc, and it re-started with some difficulty and in a lazy sort of manner, being reluctant to rev up or respond properly to the throttle. There was also a sort of low speed jerkiness. At speed, once under way, it ran well and also from cold starts.
The idle speed was also badly affected by turning on the lights, making it necessary to set the idle speed high with them off to avoid the idle becoming too low with the lights on.
This is fairly normal on small engines with a low power output, but I thought that a 200cc 4-stroke would have enough torque at idle to cope with an electrical load of about 50 or 60 watts.

After wasting several days re-adjusting carburettor, cleaning and dismantling, checking float chamber level, air leaks, ignition system, changing plugs, testing breather hole in petrol cap, fuel flow from tank, etc, etc, I was about to give up and just accept that I was beaten when I remembered my notes about valve clearances. These I did not think to check at such an early mileage.

Before doing so I searched the Net to see if incorrect clearances could affect things like the tickover and finding that it definitely could, I rushed to my garage to check them out.
I found that they were at 0.04 and 0.06 respectively, probably adjusted to the standard 0.05 and 0.08 in the factory, but due to initial valve seat settlement or recession, they had closed up in 660 Km.

I decided to reset them to the figures according to the advice of the Swedish Qingqi importer and forum contributor "CathastrophiX" (IN 0.10-EX 0.15mm).

I'm happy to say that this has cured all the troubles, the bike runs like a sewing machine and the idle speed is now steady and totally reliable.
It also pulls much better from low revs.
I just hope that I caught it on time, avoiding a burned or damaged valve seat, but for now hope that this advice is read by others with similar symptoms and acted upon without delay.

Thanks once again for all your contributions, this is what the WEB is all about.

Ernesto Forchetto
Spain

[CathastrophiX]

These bikes are also very lean jetted from factory. If I remember correct the main jet is 25 (DR200 uses 27,5)
I have 30 (or 35, a year since i changed) on mine now.
Change the rear sprocket to a smaller one from Suzuki TS125 to decrease rpms.

[forchetto]

Originally Posted by CathastrophiX

These bikes are also very lean jetted from factory. If I remember correct the main jet is 25 (DR200 uses 27,5)
I have 30 (or 35, a year since i changed) on mine now.
Change the rear sprocket to a smaller one from Suzuki TS125 to decrease rpms.

Hello Cathastrophix!, concerning jetting, mine came with 32.5 pilot and 122.5 main jets. The Pilot was opened to 34 and the slow running screw is set at 2.5 turns out. I haven't done anything with the main jet, as plug readings appear to indicate that it's OK. I live at sea level, so it might be OK for me. Owners that live at higher altitudes may need to change it.

We have to be careful when comparing the DR200 with ours. The Suzuki I think has a BST31 carburettor while ours makes do with a BST28. This could be the reason for the lower power output of the Qingqi. Ours makes 15,6 HP whilst the Suzi is around the 20HP mark.

Attempts to change the airbox and fit a K&N type pod filter have been a failure so far. These CV carbs need the airbox much more than normal slide types.
It can be done, but you lose low and mid-range torque and any wind buffeting or turbulences upset the carb at high speeds, it Wouldn't idle well, bogged off the line and didn't run well at all till wide-open-throttle.

There's lots of advice on the Net warning about the removal of the carefully designed and contoured airbox on bikes with CV carbs.

There are a few reports of things running erratically if you ditch the airbox and go with a pod. It appears the CV carbs need steady airflow to work at their best, and the minor variations in air pressure fostered by turbulence behind the pods, can upset steady carburettor function.
There's also a need for a certain air velocity, note that airboxes have snorkels shaped like a cone or a venturi-type restriction built within the case. In the Qingqi these "snorkels" are not visible, but theyr'e inside the airbox.
But then there are other folks who reckon that if you take the time and effort to get the carb/ pod filter combination jetted properly, then all is well and you are transported to the next level of motorcycling bliss. So the verdict?: think twice...