Author Topic: YSS PD fork Valve  (Read 9667 times)

0 Members and 2 Guests are viewing this topic.

Offline ji107

  • C-Grade
  • **
  • Posts: 79
    • View Profile
YSS PD fork Valve
« on: April 27, 2010, 05:05:40 pm »
Has anyone tried these fork valves, if so, are they any good? What are they like to fit?

Thanks
ji

Offline PEZBerq

  • Legend
  • *****
  • Posts: 1094
  • Brisbane
    • View Profile
Re: YSS PD fork Valve
« Reply #1 on: April 27, 2010, 05:49:52 pm »
You need to fiddle around trying various PD valve spring settings and fork oil weights to get the best results.  Takes time and needs test riding. ;D ;D

They come with reasonably clear instructions.  You need to drill out your damper rod holes as per instructions to remove the damping function from the rods so the PD valve picks up the job instead. 

You also may need to shorten the fork springs or spring pre-load spacers to allow for the length of the PD valve - about 30mm. If your springs need more pre-load then you are in luck! Shortening springs is a hassle - search other threads on this forum for info on this. One benefit of shortening the spring is it increases the spring rate - but you lose travel.

Finally you may need to machine up an adaptor or else the damper rod end itself so the PD valve sits neatly on the end of your damper rod and the oil will flow through the valve and not squirt out around the damper/PD valve seating face.

All in all peoples experience will differ.  Best to let us know what bike its for and what riding you do.  Someone may have done the conversion and can report direct.  I know lots of Husky people do it.

Husqvarnas: 78 390AMX, 82 430XC, 84 240WR, 84 500AE, 84 510TE, 87 510TE

mainline

  • Guest
Re: YSS PD fork Valve
« Reply #2 on: April 27, 2010, 06:00:12 pm »
what you husky people need is some sort of gizmo to stop your shocks falling off ;D

Offline Rossvickicampbell

  • Legend
  • *****
  • Posts: 3779
    • View Profile
Re: YSS PD fork Valve
« Reply #3 on: April 27, 2010, 06:15:18 pm »
put a set in my 74 YZ - the difference in performance was noticeable for sure.  I thought they were worth it.
1974 Yamaha YZ360B
1980 Honda CR250R - Moto X Fox Replica

Offline Freakshow

  • Superstar
  • ******
  • Posts: 7277
  • Adelaide, SA - looking for a "YZA" tank
    • View Profile
Re: YSS PD fork Valve
« Reply #4 on: April 27, 2010, 06:59:06 pm »
John, wont really help you on the road racing circuit, save yourself time and effort and just call in and see pete hoey, also on forum under same, he has tweaked a few differant set with springs, racetech emulators, sortened, longened ( ok i made that up) but he has pissed about on these for years and also sets up the RD 250/350 for the track and they are prity much the same forks.

Save yourself the time and hook up with pete.
74 Yamaha YZ's - 75 Yamaha YZ's
74 Yamaha  flattracker's
70  Jawa 2 valve speedway's

For sale -  PRE 75 Yamaha MX stuff, frame, motors and parts also some YAM DT1,2,A and Suzi TS bikes and stuff

Offline motomaniac

  • Legend
  • *****
  • Posts: 2448
    • View Profile
Re: YSS PD fork Valve
« Reply #5 on: April 27, 2010, 07:50:54 pm »
Are they much different from Racetech emulators?I think the YSSpd is cheaper or?

Offline Freakshow

  • Superstar
  • ******
  • Posts: 7277
  • Adelaide, SA - looking for a "YZA" tank
    • View Profile
Re: YSS PD fork Valve
« Reply #6 on: April 27, 2010, 08:10:54 pm »
Yes you are right, there are cheap copies made
74 Yamaha YZ's - 75 Yamaha YZ's
74 Yamaha  flattracker's
70  Jawa 2 valve speedway's

For sale -  PRE 75 Yamaha MX stuff, frame, motors and parts also some YAM DT1,2,A and Suzi TS bikes and stuff

Ji Gantor

  • Guest
Re: YSS PD fork Valve
« Reply #7 on: April 27, 2010, 08:13:11 pm »
If you are handy with a lathe you can make the two adapters required to install.
They do improve the compression of your forks.
Walter will install if you require just email and ask for a quote.

Ji

« Last Edit: April 27, 2010, 08:15:10 pm by Ji Gantor »

Offline pmc57

  • A-Grade
  • ****
  • Posts: 486
    • View Profile
Re: YSS PD fork Valve
« Reply #8 on: April 27, 2010, 08:35:15 pm »
Have a read of this, even though it refers to setting up Laverda forks, it will give everyone a good understanding of the workings of forks and what emulators do and don't do.
http://www.laverdamania.net/emulatorgb.htm

Peter

Offline Freakshow

  • Superstar
  • ******
  • Posts: 7277
  • Adelaide, SA - looking for a "YZA" tank
    • View Profile
Re: YSS PD fork Valve
« Reply #9 on: April 27, 2010, 08:47:53 pm »
YEp n
Have a read of this, even though it refers to setting up Laverda forks, it will give everyone a good understanding of the workings of forks and what emulators do and don't do.
http://www.laverdamania.net/emulatorgb.htm

Peter

good link thanks pete
74 Yamaha YZ's - 75 Yamaha YZ's
74 Yamaha  flattracker's
70  Jawa 2 valve speedway's

For sale -  PRE 75 Yamaha MX stuff, frame, motors and parts also some YAM DT1,2,A and Suzi TS bikes and stuff

Offline motomaniac

  • Legend
  • *****
  • Posts: 2448
    • View Profile
Re: YSS PD fork Valve
« Reply #10 on: April 27, 2010, 08:52:03 pm »
Have a read of this, even though it refers to setting up Laverda forks, it will give everyone a good understanding of the workings of forks and what emulators do and don't do.
http://www.laverdamania.net/emulatorgb.htm

Peter

Thanks , will do.

Offline GD66

  • Legend
  • *****
  • Posts: 1109
    • View Profile
Re: YSS PD fork Valve
« Reply #11 on: April 27, 2010, 09:49:29 pm »
... he has tweaked a few differant set with springs, racetech emulators, sortened, longened ( ok i made that up) but


Longened ? What the hell sort of a woeful effort is that, Freaky ? Everybody knows, the word is "enbiggened"... ;)
Nostalgia's not what it used to be....

Ji Gantor

  • Guest
Re: YSS PD fork Valve
« Reply #12 on: April 27, 2010, 09:52:20 pm »
VMX magazine ran a how to PD valve story some time ago.
I don't remember the issue number.

Ji

« Last Edit: April 27, 2010, 09:58:48 pm by Ji Gantor »

Offline PEZBerq

  • Legend
  • *****
  • Posts: 1094
  • Brisbane
    • View Profile
Re: YSS PD fork Valve
« Reply #13 on: April 27, 2010, 10:00:32 pm »
what you husky people need is some sort of gizmo to stop your shocks falling off ;D

Mainline it was a loose nut behind the bars that was responsible ;D ;D ;D ;D Thanks for reminding me.  Lucky the RACQ breakdown service was in attendance - thanks Andrew :) :) :)
Husqvarnas: 78 390AMX, 82 430XC, 84 240WR, 84 500AE, 84 510TE, 87 510TE

Offline ji107

  • C-Grade
  • **
  • Posts: 79
    • View Profile
Re: YSS PD fork Valve
« Reply #14 on: April 27, 2010, 10:10:17 pm »
thanks all for your info and links, most helpful

ji