I'm finally getting around to rebuilding my forks and notice that the manual calls for replacing the plastic seal that goes on the piston of the dampening rod. I couldn't find one with RPM's parts search and wonder if I missed it there or if anyone knows of an other source.
I have rebuilt my forks twice now, and the Yamaha Factory service manual does not mention anything about removing the teflon ring, or replacing it....................The Haynes manual says not to remove it unless you plan to replace it........................Both times I rebuilt my forks, it looked fine, so I just cleaned it and left it in place..........I was afraid that I would snap it in two if I tried to remove it.
Did you already remove them?
If you haven't already, you would probably better off just leaving them on there...........If you have already broken them while trying to remove them, I am not sure where you would source them............
It seems that it has been discontinued by Yamaha...........http://www.partzilla.com/parts/detail/yamaha/YP-36Y-23157-00-00.html (http://www.partzilla.com/parts/detail/yamaha/YP-36Y-23157-00-00.html)
Yamaha part 36Y-23157-00-00 is showing available and retails around 15.00 each. Randy can search it by that part number and give you a quote.
Unless you are running a valve kit with a seal (RPM valve) I recommend replacing this part. Its primary function is containing the oil in the proper location for the damping rod metering holes to properly do their job. If the rings are worn the oil can easily bypass the rebound circuit (and to a lesser degree the compression) resulting in a very loose feeling in the fork action.
Thanks Hawk. I'm using the Clymer and looking at the instructions again it is the o-ring on the ADJUSTING rod that they say to replace, not the seal on the piston of the damper rod itself.
My mistake.
BTW I've got several damper rods if anyone has broken one of those seals and can't find a replacement.
Fan,
I'm guessing there is no end gap spec for that little piece of plastic.
"In for a penny in for a pound" I've ordered a set.
I checked with my Yamaha supplier those are no longer available.
I bought a set from Rocky (Canada). 10 bucks each.
Anybody have a 3D printer? Wanna make some? :unknown:
One other thing to note, when upgrading to the RPM Fork Valve (http://www.rpmracingca.com/proddetail.asp?prod=M%2FC%3ARPMForkValve), they also incorporate a seal.
The fork valve is designed to build oil pressure by forcing it through the shim stack and not just passing it through fixed orifices. So, since the pressure range has been increased, a better seal was required.
(http://www.rpmracingca.com/prodimages/large/M%20C%20RPMForkValve-1.jpg)
The other brand of fork valve on the market, does not offer this additional seal as it relies on the face of the damper rod and the valve to create the seal.
When I rebuild and upgrade forks here at the shop, I never worry much about the factory seal being worn because the seal on the RPM fork valve more than makes up for any wear of the stock seal.
Randy - RPM
" it relies on the face of the damper rod and the valve to create the seal."
Not really.
The" other" emulator relies on the piston seal (the plastic ring) to seal between the upper and lower chambers by closing the gap between the piston and the fork tube wall. The interface between that emulator and the rod-top is a "quasi" seal with the function of directing oil flow from the rod to the emulator.
Your set up has your emulator seal perform the functions of both the "other" interface quasi-seal and the piston (plastic ring) seal.
The piston seal (plastic ring) has no function at all in your set up.
Your approach is clearly a refinement of the concept.