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Drew
30th December 2005, 19:28
Can anyone tell me, how much fork oil per leg, in an 1987 FZR750. Got me some new oil, drianed the old stuff, and cant find the piece of paper with how much i need from last time I did it!

White trash
30th December 2005, 19:45
You obviously have a computer and a connection. Google it fuckwit.

rudolph
30th December 2005, 19:56
give me 20 mins

rudolph
30th December 2005, 20:04
is that any help?

White trash
30th December 2005, 20:06
is that any help?

Nah you're thinking of fork oil quantity. I believe he's after firk oil levels.

WINJA
30th December 2005, 20:11
is that any help?
did it have the measurement in mm from the top with the spring out , its prolly a better way to do it

rudolph
30th December 2005, 20:12
as long as there even

WINJA
30th December 2005, 20:14
as long as there even
it did matter to me , less air gap is like having a stiffer spring

rudolph
30th December 2005, 20:17
dosn't need to be bang on .005 mm

VasalineWarrior
31st December 2005, 15:34
Is this because frosty had a bitch at you on the track day? Screw it man you dont need oil!

GSVR
31st December 2005, 16:20
Yeah don't put oil in use vasaline. Just heat it up on the stove and pour down each fork leg. Maybe put in a few drops of eucalyptus oil as well then your bike has less chance of catching the flue this winter.

No seriously what you should do is splash out on a new ohlins front end. I know I would if I wasn't so broke.

Amount of fork oil isn't a big issue just as long as the same amount is in each leg. Take the caps off remove the springs and bottom out the suspension. Then pour some in each leg till the oil is around (around 160mm for my SV which has similar forks) from the top (Measure with a 150mm rule or just a stick) then lift the suspension to top it out put the springs back and replace the caps.

WINJA
31st December 2005, 17:26
yeah don't put oil in use vasaline. just heat it up on the stove and pour down each fork leg. maybe put in a few drops of eucalyptus oil as well then your bike has less chance of catching the flue this winter.

no seriously what you should do is splash out on a new ohlins front end. i know i would if i wasn't so broke.

amount of fork oil isn't a big issue just as long as the same amount is in each leg. take the caps off remove the springs and bottom out the suspension. then pour some in each leg till the oil is around (around 160mm for my sv which has similar forks) from the top (measure with a 150mm rule or just a stick) then lift the suspension to top it out put the springs back and replace the caps.
dont forget to pump them to get all the air out b4 measuring .
if your a broke prick transoil works ok and is about 10wt

riffer
31st December 2005, 21:35
Sorry Drew, just noticed this thread.

434cc oil.

With the fork fully compressed, measure 138mm below the top of the inner fork tube.

R1madness
1st January 2006, 09:45
Sorry Drew, just noticed this thread.

434cc oil.

With the fork fully compressed, measure 138mm below the top of the inner fork tube.

yEP THOSE WILL WORK FINE BUT ABOUT 100YEARS AGO WHEN I RACED ONE WE USED 10WT OIL AND FILLED IT TO 125MM GAP WITHOUT THE SPRINGS AND THE FORKS FULLY COMPRESSED. IT GAVE THEM MUCH BETTER MID CORNER HANDLING.

"CAPS HAVE BEEN USED IN PROTEST TO WINJA :shutup: BEING INFLICTED WITH THE HUMILIATION OF BEING CAPLESS. POOR BASTARD."

R1madness
1st January 2006, 09:52
Amount of fork oil isn't a big issue just as long as the same amount is in each leg. Take the caps off remove the springs and bottom out the suspension. Then pour some in each leg till the oil is around (around 160mm for my SV which has similar forks) from the top (Measure with a 150mm rule or just a stick) then lift the suspension to top it out put the springs back and replace the caps.

EH? WHAT ARE YOU ON? IT MAKES A HELL OF A DIFFERENCE. THINK OF IT LIKE AN EXTRA SPRING IF YA REDUCE THE AIR GAP YOU NEED MORE FORCE TO COMPRESS THE LESS VOLUME OF AIR. iTS SIMPLE PHYSICS.

"THIS HAS BEEN TYPED IN CAPS IN PROTEST TO WINJA HAVING BEEN CASTRATED. POOR BASTARD"

WINJA
1st January 2006, 11:58
eh? what are you on? it makes a hell of a difference. think of it like an extra spring if ya reduce the air gap you need more force to compress the less volume of air. its simple physics.

"this has been typed in caps in protest to winja having been castrated. poor bastard"
im glad someone else understands this

GSVR
1st January 2006, 12:12
im glad someone else understands this

Only issue is if you don't have enough gap then you hydraulic the seals.

Boyles law states that if you half the volume of a gas the pressure is doubled. So if you have 1 bar pressure in your forks if there was No Air Gap fully compressed the pressure at half travel would be 2 bar. And at 3/4 travel 4 bar.

Now considering the air gap is over 100mm. You do the math.

GSVR
1st January 2006, 12:39
Heres a graph from Ohlins for upside down forks which are far more sensitive than conventional forks to oil levels.

WINJA
1st January 2006, 13:38
only issue is if you don't have enough gap then you hydraulic the seals.

boyles law states that if you half the volume of a gas the pressure is doubled. so if you have 1 bar pressure in your forks if there was no air gap fully compressed the pressure at half travel would be 2 bar. and at 3/4 travel 4 bar.

now considering the air gap is over 100mm. you do the math.
hydraulicing the seals is not the only issue , that air gap effects performance including midcorner grip on the road

WINJA
1st January 2006, 13:42
heres a graph from ohlins for upside down forks which are far more sensitive than conventional forks to oil levels.

that graph says air spring , is it for calculating the effect of the air gap + the spring?

GSVR
1st January 2006, 14:38
Lets get back to the original question

"Can anyone tell me, how much fork oil per leg, in an 1987 FZR750."

And I stand by my original reply the the fork oil level will not make a huge difference as long as both legs are the same level and theres a reasonable air gap. On an older bike I'd be going for less oil rather than more.

That graph is refering to the spring effect in the air being compressed and I only posted it to show it has FA effect until your forks bottom out and then on bikes like mine and this old FXR probably almost none at all.

Page 59 of January Kiwirider 2005 explains just how complicated things can be to get your front wheel to comply with every ripple and bump in the road and most of it is concerned with shalf velocities and digressive rather than progressive compression curves but that is what modern cartridge shocks are all about right?.

riffer
1st January 2006, 20:30
My source is the Haynes FZR 600, 750, 1000 manual.

And I've tried a few different settings in the old bike (FZR750) and found most didn't work.

This setting does. I had the preload set reasonably high but I weigh more than Drew.

Drew
4th January 2006, 16:21
Is this because frosty had a bitch at you on the track day? Screw it man you dont need oil!
Sort of, I went for one of our thursday rides last week, and deano and myself couldn't get past Mikey! On the way home I began to wonder if I had my front end set up corectly? Answer, NO!!! There was fuck all fluid in either side, I must have under filled it last time I did the seals, cos there aint no leaks.
I went and got some more, and now I'm trying to get it right.

VasalineWarrior
5th January 2006, 09:09
Probably more to do with Mikey being a bloody lunatic rather than an affront to your overtaking abilities bro