~TABASCO~
RIDE ON ADV is what I do !
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Next time in my forks I will have to pay close attention to that! thanks. I need to service them soon!
I think it's 10 on fork and 30 on the monoshock but I might be mistaken, don't remember.Compression is on bottom and doesn't have anything to do with the 'nut'....... the rebound is on top and L & R should be the same (on stock forks) I thought It was like 13-14-16 clicks... (I would have to check in the book)
I've done XT1200 Forks three separate times, and each time I have measured the fluid height exactly as stated in the shop-manual.Could it be that my yamaha tech poured too much oil in there?
Manual says 505mL per side, as far as I know, so we separated one liter equally into 500mL on each side. We didn't measure, only followed the volume specs.
However, it has been my understanding - and correct me if I am wrong - that oil volume has more to do with total travel, whereas oil viscosity determines the ease or difficulty of travel (ie. the amount of friction generated as the oil passes through the valving). How would reducing oil level increase traveling speed / ease of the fork? Thanks
Thanks, I am waiting for the levle measurement tool to arrive (yamaha here doesn't have one!), and I'll go there and get this sorted. Gotta recheck everything; it's clearly not right.I've done XT1200 Forks three separate times, and each time I have measured the fluid height exactly as stated in the shop-manual.
If you do it right and bleed all the air out the way you're supposed to, and measure the level like you are supposed to, you should end up with some fluid leftover out of a 1-liter bottle.
If your tech-person just divided it up equally and dumped half in each fork then it is over-filled slightly...................enough to really matter? Maybe not?
This is my experience using a 1-liter bottle to fill both forks.
Thanks, I am waiting for the levle measurement tool to arrive (yamaha here doesn't have one!), and I'll go there and get this sorted. Gotta recheck everything; it's clearly not right.
Thanks brotherUse a long zip tie as a dipstick for your measuring tool. Dip it down into the fork all the way till the head of the zip tie rests on the fork, then pull out and measure with a ruler your fluid level. No need for fancy tools.
Ok here is my very uncontrolled experiment on fork oil wieghts. I have maxima 5w and i have PJ1 01w oils on hand. I filled a syringe to the top and timed the flow till empty. While the 5w to the eye looks very thin and as thin as the 01w but with a stop watch it takes consistantly just over 3 seconds longer for it to drain out. That sounds like a big jump in viscosity to me. Piddling in the shop today. Thought i would test it.OK, so an update.
One fork had a whopping 80mL excess, and the other 50 to 60. I also found that one of the spring guides were inverted. The high oil levels are likely the cause of the felt hydrolocking when hitting an object very hard, but does not explain the harshness of the fork at low speed nor by minor bumps. We fixed the excess oil (leveled air depth to 150mm with the spring taken out and fork fully compressed) and also calibrated the screw height that tabasco was talking about (it should be 12mm from screw top to axel top). Re-used my 5W viscosity fork oil as it has 3 months of use.
Long story short, the fork is still very rigid even with stock springs.
I am getting increasingly suspicious that 0W is the original oil viscosity, despite reading numerous claims of otherwise. Or maybe the fork oil I have received was simply poorly calibrated and much thicker than it should be (I have read the posted earlier that viscosity is a complicated topic, but nonetheless, reducing from 15W to 5W should show a marked difference and it has not).
Or, my fork is simply fucked. But that would be strange, considering no crash or any similar problems.
Sag is perfect at 6.2cm. We set the torqued the triple clamp to ensure that there would not be stiction (20Nm inferior and 26Nm upper clamp).
I tested the calibration screws (clickers) when I had the fork legs separated, by hand, screwing them all the way in and all the way out, and they cleary work.
So, again, the only thing I am left with is the choice to reduce viscosity. The tech at yamaha keeps saying "I think it's 0W" but he's not sure, and the manual obviously does not state the generic viscosity, just the compatible yamaha product. I keep hearing everyone on this forum saying 5W -- so I really don't know what to think anymore.
What am I missing?
Thanks guys
3 times longer; I knew it. Thanks, this is very helpful. Gotta open this crapup ONE more time, then... And finally finis with this.Ok here is my very uncontrolled experiment on fork oil wieghts. I have maxima 5w and i have PJ1 01w oils on hand. I filled a syringe to the top and timed the flow till empty. While the 5w to the eye looks very thin and as thin as the 01w but with a stop watch it takes consistantly just over 3 seconds longer for it to drain out. That sounds like a big jump in viscosity to me. Piddling in the shop today. Thought i would test it.
I’ve read about it, mostly negative as such. But seeing as there’s no compatible oil here in my area I might try the engine oil meanwhile …Fork oil, I quit buying fork oil many years ago and switched to synthetic automotive transmission fluid .seems to work about the same and much cheaper.
There was a time many years ago when there was no such thing as fork oil and most service manuals called for ATF in forks. Back then forks were pretty simple, but todays forks are a lot more complicated and it's probably best to use modern fork fluid with the needed additives for the best performance.Fork oil, I quit buying fork oil many years ago and switched to synthetic automotive transmission fluid .seems to work about the same and much cheaper.
ATF fluid and fork oil are very similar, I wouldn’t recommend trying engine oil In fact I wouldn’t recommend using anything but what the manufacturer recommends, but ATF fluid is what I have been using for many years and it’s never caused me any trouble so I’m going to continue using it.I’ve read about it, mostly negative as such. But seeing as there’s no compatible oil here in my area I might try the engine oil meanwhile …
The manufacturers W numbers bear no resemblance to the viscosity.
The Yamaha manual recommends Yamaha Suspension Oil M1 or Ohlins R&T43.
Both of which seem pretty scarce in the uk. A US site tell me that Yamaha M1 is a zero weight oil but no viscosity figures. The Ohlins site however was more helpful giving a viscosity of 19 mm2 Centistokes @ 40° C. So I had a reference point to aim for.
I contacted Opie Oils for some advice and Tim (very helpful) set about finding me some suitable oil.
His first recommendation was for any 5W oil until I pointed out that it was the viscosity that was the critical factor as the 5, 7.5, 10W etc bore no resemblance to the viscosity. Telling him my aim was a viscosity of 19. He came back again with a recommendation for Motul Light 5W Factory Line Motorcycle Fork Oil which has a viscosity of 18, so close enough for me. I then set about finding others that were in the same range so I had a choice.
Fork Oil recommendations for the Yamaha FJR 1300A
Centistokes @ 40C
Millers Suspension Oil 2.5 NT 17.2
Motul Factory Line 5W Light (Synth) 18
Motul Expert 5W Light (Semi Synth) 18
Red Line Light Weight Suspension Fluid 16
Silkolene 02 17.94
Garry, what's your weight and how much sag do you get with these springs? I'd like a linear spring that gives me 6cm (perfect) of sag with zero preloadFork oil level is measured with the fork fully compressed and without the spring. I use kyb 01 fork oil and .95 constant rate springs from Sonic.