Fork overhaul

[JohanB]

Hi
I have Tiger 955i -06 that I'm planning to give some love during the upcoming winter and what I particularly have in mind is to overhaul the front suspension.
This bike has been rolling over 50000km now and has probably never had the suspension serviced before (I just owned it since last spring).
First I was thinking of just replacing the oil,,, but then I was expanding this job in my mind to also include upgrading to progressive springs and/or (?) a cartridge emulator of some kind.
Can someone please point me in the right direction, links or advice is welcome.
I'm not really unhappy with the shock performance now but it does have that "clonky" sound that most girlies seem to suffer from,,, and it does feel quite saggy too...

[nickjtc]

Welcome. The more experienced members here will chime in shortly, but if you are basically happy with the performance of the front end now perhaps you will not have to do many changes...

[Bixxer Bob]

If you want to go to extremes Chris Canning will be along to talk about his setup.  Mine is more or less stock, but be aware there is confusion even with the stock arrangement because Triumph changed the forks during the later 955i run.

First, the oil weight; I wrote about this recently.  the recommended oil is Kabaya 10W which is no longer available.  Unfortunately one make of 10W is not necessarily the same as another make as the standard is very loose.  Viscosity is a better measure and the closest I have found to the Kabaya is Silcolene 7.5W, it's almost spot on the same viscosity.

Next the air gap.  Haynes manual says 107mm across the board, but the Triumph manual says 107mm for the early ones, 146mm fro the later ones   from VIN 198875.  That's a big jump and mine is a later one but I bottled out and set it at 107mm.  So far it seems ok.

[Chris Canning]

Most of what I have learned is 955 pre 04 the later forks are a different animal so I'm no use I'm afraid.

[JohanB]

Just for your info:
I removed both fork legs yesterday and noticed:
- missing about 0.5-1dl oil in each leg (no noticeable leakage)
- Brown oil in one leg and red in the other (both quite mucky)
- Standard (non-progressive) springs.

Put in Motorex 10W (red) oil 146mm from top w.out spring (about 6.5dl)
After just testing the fork operation in the garage I must say that it feels MUCH smoother now and without the initial over-softness. Looking forward to test it on/off road.
But one thing that surprised me was that there were almost NO spring tension on the top nut when i removed it!???
Every "how-to" guide I have watched or read have warned about this and I just wonder - do the springs loose tension after some time and have to be replaced because of this?

[Bixxer Bob]

   it can happen, but I have very little spring pressure on mine either, I've had it since 4k miles and always been like that.

[Sasquatch]

Almost every set of forks I take apart has had different fork oil levels in them right from the factory.  One would think with automated assembly it would be consistent, but it is not.  Another thing that baffles me is that every manufacturer is installing suspension springs that are far too soft for real riders.  Simply doing nothing else but servicing your forks and installing proper rate springs so radically improves the ride of the bike that it blows me away that the factories have it so wrong.

[Bixxer Bob]

Have you read my bit about fork oil viscosity variances for the same weight number Sas?   You'd think 10 W would be the same regardless of manufacturer, but it's not, far from it.

[Sasquatch]

Have you read my bit about fork oil viscosity variances for the same weight number Sas?   You'd think 10 W would be the same regardless of manufacturer, but it's not, far from it.

I have and you are right.  That is why as a tuner we stick with one brand and set up our valving specs on that brand of fluid.  Quite frankly, for forks on our Tiggers, I find simple ATF to work fantastic for most people.  I run it myself.

I wish there was more consistency within the industry.

[nickjtc]

I find simple ATF to work fantastic for most people.

If I remember rightly, Honda used to specify ATF for the forks of their '60s bikes.

[Bixxer Bob]

I have and you are right.  That is why as a tuner we stick with one brand and set up our valving specs on that brand of fluid.  Quite frankly, for forks on our Tiggers, I find simple ATF to work fantastic for most people.  I run it myself.

I wish there was more consistency within the industry.

Not come across ATF; I've got 36k miles on my Girly, and have to say that since I switched to Silkolene 7.5W (the nearest available oil to the Triumph recommended Kabaya 10W I could find) she is handling better than she has for a long time.  Last couple of fork oil changes I (in my ignorance) used Motul 10W which has less viscosity.

[Chris Canning]

15wt Silkolene for me.

[Bixxer Bob]

Flippin' heck Chris, they must be stiff as f@@k 

[Chris Canning]

And an increase in oil quantity!! normally 30 miles to warm the job up but with 17" front wheel with a sport tyre I can really lean on the front end,it's why when I test rode the XR the other day great motor and the bike is lighter but they way the rolling chassis worked not better than my tiger.

[threepot]

Almost every set of forks I take apart has had different fork oil levels in them right from the factory.  One would think with automated assembly it would be consistent, but it is not.  Another thing that baffles me is that every manufacturer is installing suspension springs that are far too soft for real riders.  Simply doing nothing else but servicing your forks and installing proper rate springs so radically improves the ride of the bike that it blows me away that the factories have it so wrong.

Out of curiosity,what's your view on using engine oil? Some do?