Fork oil

[Mark Straughn]

What is a good starting point on a 125 Six Day w/35 mm forks for oil weight and volume. Fighting weight of 210#.   Thanks

[Richard Colahan]

Should be MANY opinions on this one...

Back in the day ATF was the hot set-up!

But today I guess I'd start with 20wt quality fork oil.
With springs removed...somewhere between 5" and 6" from top of inner tube with outer leg compressed.

Richard Colahan
1969 V1225
Upper Black Eddy PA

[brian kirby]

ATF

Brian

[Gary Roach]

We use 15wt oil, 6¼" measured from the top of the tube with the springs removed and the forks collapsed.

[Mick Milakovic]

Gary, do you remove the legs from the triple trees to allow the oil to lay "flat?"

Mick

[Gary Roach]

Mick,

Most of the time when we replace the fork oil, we have them off to replace the seals.

You can try and leave the forks in the triple clamps, but when you collapse the fork, make sure that the fork is bottomed out, and not just the dust seals hitting the lower triple clamp.

[tooclose racing]

Resurrecting an old thread to ask if anyone knows the volume/capacity (in cc) for the 35mm Ceriani fork used 74-75.  I know the golden rule of 6 in from the top, springs out, collapsed.  Just looking for an equivalent without needing three hands, so to speak (hold bike up to collapse forks, etc).

[Rocket]

35mm Ceriani straight leg.
235cc total disassembly
220cc for just an oil change.

[Mike OReilly]

Search "fork oil amount"
There is a totally comprehensive chart for all forks, used for all years of Pentons, with 2 numbers: rebuild or fluid change only, courtesy of Rod (Rocket).
I know for me I printed it out and filed with my manuals.
Would be nice if it could be pinned on this site.

[skiracer]

Mick,
Remove one fork leg, install the oil to the 6" mark, reinstall the fork into the triple tree, remeasure that leg, and that becomes your new measurement for future reference.......

quote:Originally posted by Mick Milakovic

Gary, do you remove the legs from the triple trees to allow the oil to lay "flat?"

Mick

1976 250 MC5 Original Owner
1976 Penton 175 XC

[tooclose racing]

Thanks to Rocket and Mike O'Reilly. Funny thing - i rebuilt one fork and not the other, so I'll use your recommended amounts for each leg and...check it with a ruler!  

Ski (James) - you are replying to a Mick post from 2015. Just saying. Will you be at White Lightning this year?  That's about as far south as I can EVER go (wait - what latitude is Barber at?)

[Larry Perkins]

Motion Pro makes a cool syringe thing with a settable needle that lets you measure the heigth and sunction out to that heigth.  Well worth the money and very accurate.

Larry P

[tooclose racing]

Thanks Larry.  

I "attempted" the 535 and 520 measurements with my ratio-rite and...drum roll...this results in oil being ~ 5.5 inches from the top of the tube. My "520" leg ended up being a little higher, understandable if not completely drained.

I have a very scientific way of taking oil out of the fork tube.  I keep dipping and wiping off tape ruler till I reach level I need.

I also successfully installed new 74/75 (black letter) tank stickers on my MX Jackpiner tank today. No wrinkles, no mess.  Please subscribe to my YouTube page and you too can...Just Kidding.  My YouTube version would actually be...how to install stickers while holding a beer in one hand. Now THAT is some serious mechanics!