QingQi (Qlink) 200GY Illustrated Valve Adjustment

[Real4real]

The sales department sent the english version of the specs reqested, the request was sent to the enginering department who wrote these specs to sales in Chinese. I have this all in my inbox but didn't feel the need to share this and edit the email addresses to post the requested information here.
I'll give you and E for effort to prove your point.
By the way, the clearences given are the clearences requiered for oil to lubricate the cams, rockers and valves. By setting your exaust clearences loose you are in fact changing the duration of the exaust valve, causing it to close sooner and in some cases increasing the power of the engine. This is incorrect and very poor mechanical practice to gain a half a horse. Some engines allow you to dial in the cams to achieve changing the duration without causing damage to the valve train. Also your rocker to valve clearences increase in modern Chinese engines when the engine gets hot due to the geometry of rocker pivot to valve contact hight together with the thermal growth of the rocker itself.
Please stop posting poor information, there are people visiting this forum for information to maintain thier engines and the info your posting and trying to prove could cause damage to an engine. The clearences your posting to use are old school enginering.
My 2009 China bike uses a Suzuki based engine still in production except for the rocker system, this has been updated with better materials and re-enginered to reduce excessive clearences reducing noise and increasing the max RPM and power output. The Suzuki engine has been in production for a while and the Japanese haven't bothered to update this design because the engine is selling as an entry level power sorce and re-tooling for a couple of horse power isn't economical. Yes I am saying the Chinese engine in my bike is better in some ways than the Suzuki engine it's some what based on.
I have never done sales myself, in fact I am a profesional maker. I have done it all, CAD design of parts and assemblies, pattern making for casting production, machining the parts for assembly and assembly the mechanical finalization of the making process. I have done this for small engine, automotive and large engines with pistons that required a crain to be lifted and many other applications. That's how I know my stuff. Nice try again.
You are obviously an amature mechanic who thinks too much of yourself MJH. I have been clear and reasonable with my experience and defined my reasons for giving the advice I've given. The only thing I have seen from you MJH is insults to the manufacturers of the bikes I thought we all enjoy. Try to dig up some facts or proof of the accusations and poor mechanical practices you so easily pass around.

[modron]

I want to adjust valves on my YBR250 cos seems that a maintenance check after my China trip (16000km) skipped this part. I told the mechanics to do that and went off to a shop, returned 15min later and they said its been done. I didnt notice any difference in noise and the engine isnt as nippy as for the first few thousands km. After reading this guide i sure it would take them longer than 15min so they just lied to me.....ehhhh
Ill try to do it myself but im not sure about the numbers, found this online
Intake valve: 0.05 - 0.10mm (0.002 - 0.004inch)
exhaust valve: 0.08 - 0.13mm (0.003 - 0.005inch)

can anyone confirm this?

[Real4real]

The manufacturer will give you the exact specs to suit your specific engine. Try sending them an email, any that I have tried both China bike and mainstream Japanize manufacturers and they got back to me in a couple of days.
Be sure to try to slip your feeler guage between valve and rocker before you start changing anything, if you can't get the thinest feeler guage in between ajuster and valve this tight valve may be open slightly while your bike is running. If a tight valve*is suspected be sure to check your new settings once cooled down after a good ride. This was the case with my bike at my first 500km check and after I corrected the tight valve this valve must have re-seated and/or knocked out some carbon and tighted up again and required another ajustment.
Good luck and be sure to take your time ajusting your valves. This is one of the most important easy to do settings to get the best performace on any bike.

[MJH]

I want to adjust valves on my YBR250 cos seems that a maintenance check after my China trip (16000km) skipped this part. I told the mechanics to do that and went off to a shop, returned 15min later and they said its been done. I didnt notice any difference in noise and the engine isnt as nippy as for the first few thousands km. After reading this guide i sure it would take them longer than 15min so they just lied to me.....ehhhh
Ill try to do it myself but im not sure about the numbers, found this online
Intake valve: 0.05 - 0.10mm (0.002 - 0.004inch)
exhaust valve: 0.08 - 0.13mm (0.003 - 0.005inch)

can anyone confirm this?

I would not use that if you found it on Wiki answer.
http://wiki.answers.com/Q/Yamaha_Ybr...alve_clearance


They recommend the dealers mechanic do it.
http://ybrclub.com/_files/books/yama...ner_manual.pdf

[MJH]

I would go back to the mechanic and say
你做了什么，是不正确的失去动力

[modron]

Real4realthanks, I emailed Yamaha customer service, hope they will give me an answer soon. MJH youre correct, its from wiki answers thats why I wanted to confirm this.
Im pretty sure that the mechanics didnt do anything apart from taking the panels off. They were taking it off when I left and putting it on when I came back. Im bit scared of adjusting the valves by myself but one has to learn somehow ;)

[MJH]

Whilst you are waiting.

I am fairly certain that most manufactures will direct you to an authorized service center. They will not likely offer you the specifications that would lead you to do what they recommend having a mechanic do. page 6-12 in the the owners manual.

Its for a 2007 though, but likely is the same as yours.

[MJH]

I would like to add that professional mechanics use authorized publications from the manufactures and all respectable manufactures offer shop manuals….


I have three motorcycles and have three shop manuals, two are Hondas and one is a Qlink, to the best of my knowledge the shop manual for the XP200 is the only existing shop manual for any Chinese manufactured motorcycle, that is not a Japanese motorcycle, that happen to be made in China, like your YBR250.


I do pay mechanics to do work for me, but would never ask them to make an adjustment without making sure they had the specifications. I know the valve lashing clearances on all my motorcycles, I would not buy one that does not offer that in a professional publication that I can readily buy. Which would be just about every Chinese manufactured motorcycle….except the one I own.


The 250cc version of my motorcycle does not offer a shop manual and has no authorized service centers.
The people selling them may say they do…but without a professional shop manual published then how can they authorize a services center? Oh I know they just authorize anyone that buys their stock and sells them.


I am totally sure that the Chinese do not publish service manuals because they cost money and they will get copied, they probably are waiting for others to make them so they can save money and just copy theirs. It is what they do….copy everything, its cheaper.

[modron]

Thanks MJH,
I didnt even know that something like service manual exists. I did some googling and found one for free but its in spanish. I do speak some spanich but its only conversational, my vocabulary ends with "valvulas". There are a lot of numbers in the chapter about valvulas but I think the ones that I might be looking for are on one of these screen shots below.... any spanish speaker?
I think its the second one cos the first one is rather small hahah ;)

Unnamed QQ Screenshot20130907213935.jpgUnnamed QQ Screenshot20130907213914.jpg

[MJH]

yeah the second is for the valve seats.
the clearances are the same for exhaust and intake on that bike.
there is a note at the bottom about the contacted surface area and that the color blue is removed?