Yamaha TRX850 Enthusiasts Forum

Situation I have put myself in this time:

Checked the valve clearances. Need of adjustment emerged. Went to get some adjusting pads. 300 km's later start to think of silly things like which pads I'm supposed to get. Only then it occurs to me that maybe the originals pads, which I did not check, are not all of the very size given in the spirit of example in the service manual. Stupid me.

As I really wouldn't like to make a 600 km round trip to dig out the pads, I ask you, my more enlightened brothers and sisters, what kind of range of original pad sizes should I be thinking of when calculating the sizes of new pads? What pad sizes did you encounter when doing valve clearances for the first time?

Or should I even be doing this on my own given my dazzling start...

Thanks again for your help!

LozLul wrote:Situation I have put myself in this time:

Checked the valve clearances. Need of adjustment emerged. Went to get some adjusting pads. 300 km's later start to think of silly things like which pads I'm supposed to get. Only then it occurs to me that maybe the originals pads, which I did not check, are not all of the very size given in the spirit of example in the service manual. Stupid me.

As I really wouldn't like to make a 600 km round trip to dig out the pads, I ask you, my more enlightened brothers and sisters, what kind of range of original pad sizes should I be thinking of when calculating the sizes of new pads? What pad sizes did you encounter when doing valve clearances for the first time?

Or should I even be doing this on my own given my dazzling start...

Thanks again for your help!

I think someone said....search is your friend

http://trx850.motomaniac.net/forum/view ... ims#p26483

And wise words thay are! Alas, in this case search magic didn't answer my seemingly poorly put question. I try to be more precise:

In order to be able pick a valve adjusting pad of a correct the thickness (not diameter) you need to know the clearance and the thickness of the old one. In my case I foolishly presumed that original pad are of standard thickness (175 as in service manual example). So, now I'm looking for a range of thicknesses found in original pads when adjusting the valves for the first time. This way I can pick up a set of pads that are most likely able to solve my clearance woes.

But thanks for the search link, Killerwhale. It reminded me that I don't neccessarily have to buy original Yamaha items now that I know the diameter of the pads. This should do me some good price-wice especially as I'm inclined to buy more than your standard amount of pads to cover the scope of my inconsideration.

LozLul wrote:And wise words thay are! Alas, in this case search magic didn't answer my seemingly poorly put question. I try to be more precise:

In order to be able pick a valve adjusting pad of a correct the thickness (not diameter) you need to know the clearance and the thickness of the old one. In my case I foolishly presumed that original pad are of standard thickness (175 as in service manual example). So, now I'm looking for a range of thicknesses found in original pads when adjusting the valves for the first time. This way I can pick up a set of pads that are most likely able to solve my clearance woes.

But thanks for the search link, Killerwhale. It reminded me that I don't neccessarily have to buy original Yamaha items now that I know the diameter of the pads. This should do me some good price-wice especially as I'm inclined to buy more than your standard amount of pads to cover the scope of my inconsideration.

Found on the Swedish forum that Swedish company Jofrab has a full kit of shims for about 50€....maybe something for ya??
The art.nr. is: 46-54-852
(http://www.jofrab.se)

I'd expect that you mostly want 170, 165 or 160 shims. Just a very wild guess. This assumes that your clearances were too small. Maybe down to zero?

Imo it is not worth getting shims in the range 200 upwards cos you will never need them on a TRX.

Thanks for the link, Killerwhale!

youngy,

Right you are. The clearances were in the region of 0,05 at the intake and 0,10 at the exhaust. Should the original pads be 175's, the new ones would be 165 at the intake and 160 at the exhaust. But can i trust the size of originals to be in the neighbourhood of 175?

Not exactly - they'll be between 180 and 190 most likely.