Assembly question on an old yz 125

[poop1st]

Hi, The other day i got a very cheap old 1990 yz 125. not working. I've since fixed it (head gasket among other things) and got it running last night and seems fine. The thing is theres an outlet valve (i don't know it's name) on the barrel which moves up/down via a push rod type thing coming up from near the clutch area. It wasn't properly connected when i got the bike. It screws on but there is also a piece thats seems like it should be held in place with a lug or screw (theres a spring attached to it which i might asume is what returns the valve back). Any help, pictures or diagrams of how it should be kept in place would be much appriaciated. Cheers George :fft:

 

[QKENUF4U]

just go here and check out the fiche for your bike www.mrcycles.com
good luck

 

[Sawblade]

Hi, The other day i got a very cheap old 1990 yz 125. not working. I've since fixed it (head gasket among other things) and got it running last night and seems fine. The thing is theres an outlet valve (i don't know it's name) on the barrel which moves up/down via a push rod type thing coming up from near the clutch area. It wasn't properly connected when i got the bike. It screws on but there is also a piece thats seems like it should be held in place with a lug or screw (theres a spring attached to it which i might asume is what returns the valve back). Any help, pictures or diagrams of how it should be kept in place would be much appriaciated. Cheers George :fft:

You are describing the powervalve assembly. The linkage is connected to the powervalve with a bolt, washer, spring and a few other pieces that you can look up on the link provided by QKENUF4U. There is a small hole in the casting that houses the powervalve. A small pin goes in this hole to align the powervalve when you re-assembly it. This is needed to ensure the powervalve opens at the correct RPM's. If you do not have a manual for this bike, I would suggest picking up a Cylmer manual, this way you will have a resource on the work bench to refer to as needed.

Good luck! :cool:

 

[Kevin003]

This blueprint may help you out http://houseofmotorcycles.bikebandi...del_dept_id~410610~model_dept_name~YZ125A.asp

 

[John Cena]

Here's some pics can you tell you tell exactly what part it is?

Pic 1 Click


Pic 2Click