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Skunk
12th November 2007, 20:02
I've decided to change the fork oil on the old RD and had a lookie in the service manual:

253cm3 of SAE 10W30 SE motor oil. WTF!?

So; knowing some of you race the critters - what do you use and how much?

These forks are standard AFAIK. No emulators, no air valve etc.

Paul in NZ
12th November 2007, 20:54
Be careful - any deviation from std will validate the warrenty...

Back in the day - we didn't have fork oil - we used atf or engine oil...

riffer
12th November 2007, 21:08
Pretty simple I would have thought. Doesn't the viscosity rating measure the viscosity at cold and hot temperatures?

Therefore you look at the cold temperature. And 10 weight fork oil should do you fine.

Now - is that 253cc PER fork, or total?

Skunk
12th November 2007, 21:38
Pretty simple I would have thought. Doesn't the viscosity rating measure the viscosity at cold and hot temperatures?

Therefore you look at the cold temperature. And 10 weight fork oil should do you fine.

Now - is that 253cc PER fork, or total?
Per fork. Shows how new to biking I am huh? Never seen motor oil specified before.

It didn't have engine oil in there - it was fork oil. I was going to use 20 weight as the front end is rather bouncy (and 'plush').

Skunk
12th November 2007, 21:40
Be careful - any deviation from std will validate the warrenty...

Back in the day - we didn't have fork oil - we used atf or engine oil...
Bugger; didn't think of the warrenty... Shouldn't of changed the tyres I guess.

riffer
12th November 2007, 21:54
It didn't have engine oil in there - it was fork oil. I was going to use 20 weight as the front end is rather bouncy (and 'plush').

And you don't care how many fork seals you blow...

Wouldn't you be better trying heavier springs and using the original weight fork oil? You're less likely to push the components past their performance limits that way...

Skunk
12th November 2007, 22:03
And you don't care how many fork seals you blow...

Wouldn't you be better trying heavier springs and using the original weight fork oil? You're less likely to push the components past their performance limits that way...
Heavier springs are out of the budget at this stage so I'll be getting some fork oil and seeing how std settings go. I think it'll be a little soft though.

I was hoping for some input from the guys who race them in pre 82 so as to save me pissing about trying to get them right by trial and error.

Kickaha
13th November 2007, 05:26
I was hoping for some input from the guys who race them in pre 82 so as to save me pissing about trying to get them right by trial and error.

All those who race them down here pretty much say the front ends are crap no matter what oil you put in them and they're also undersprung

PM Dangerous and/or Bren_chch they've both had there's modified and might tell you what was done

Robert Taylor
13th November 2007, 07:59
Heavier springs are out of the budget at this stage so I'll be getting some fork oil and seeing how std settings go. I think it'll be a little soft though.

I was hoping for some input from the guys who race them in pre 82 so as to save me pissing about trying to get them right by trial and error.

Irrespective of cost emulators ( even without doing springs ) is the very first thing you should do. Very poor hydraulic control is 70% or so of the problem with forks such as these.