Intiminator Compared and modified

FWIW out of the box the set of Intiminators purchased and installed in 2016 on Gen2 stock springs had firmer initial response but would bottom out and showed signs of insufficient rebound damping on 17Cst@40c Sikolene Pro RSF mix. Going to heavier springs and straight Sikolene Pro RSF 5w (26Cst@40c) with no valve modifications had fixed rebound, bottoming out and initial harshness without noticeable impact on high speed compression damping.

On shim damping circuits oil weight does not have much impact on high speed damping; it increases initial firmness/low speed damping but when valve opens wider damping characteristics defined by shim stack not oil weight. Initial firmness could be delt with by reducing preload (and correspondingly choosing higher spring rate to reduce sag/bottoming out) as it will result in higher initial velocities.

Bump, for a thread started over a decade ago!

Got Intiminators in my '87 Transalp (in UK), and it has the often reported oscillation at about 40mph on apparently smooth roads.

Stock springs, stock air gap, and 5W Amsoil Shock Therapy oil. I weigh 175lbs dripping wet.

My understanding of the dark arts of suspension tuning is sketchy to put it mildly, so I'm not overkeen to be altering shim stacks or port diameters or the other variables expertly described in this thread. Besides, under all other riding circumstances I think the Intiminators are great, and even with the oscillation are - as others have said - hugely better than stock.

But I've seen the 1mm bypass hole mod mentioned on here, and various Strom and Triumph forums, as a means of addressing the oscillation without significantly adversely effecting Intiminator performance under other circumstances. I think I'd like to try this.

All of which is a very long winded way of asking if I am right in thinking this is simply a 1mm diameter hole drilled right through the centre of the bolt that holds the whole Intiminator together? A photo would be ace, if anyone has one?

Thanks

No photo but you are correct. Its just a hole drilled straight through the center bolt.

What is this oscillation?

Try heavier oil. More likely fork oscillation feel is due to rebound not compression, and Ricors don't have stack for rebound just for compression.

Below the link to oil viscosity comparison chart. Just beware that the numbers are given for 40C and 100C, and unlike shocks forks have large surface and oil capacity and run at ambient temperature 5-40C, so some of the synthesis with high viscosity index may be actually thinner at operating temperature.

https://www.peterverdone.com/wiki/index.php?title=Suspension_Fluid

Its an up and down movement noticeable when riding on a smooth surface. Not everyone experiences it. Sometimes also described as Wheel Bounce, although (certainly in my case) the movement is only slight and the wheel definitely doesn't leave the ground!

Plenty about it in places like Stormtrooper and TriumphRAT, eg

https://www.triumphrat.net/threads/ricor-oscillation.585682/

The other question is: do you have the right spring rates for your weight? What you are describing is usually a sign of either insufficient damping or soft spring. It could be also caused by disbalance between front/rear. For example if rear is overdamped or too stiff for front, then most of the energy goes into forks and it is more than it can handle. Softening rear shock can/will fix it.

It is fool's errand to try to fix insufficient spring rate with damping.. have been there more than once. RaceTech has spring rate calculator; see if you are off by much fix it before going any further.. at least get the sag right good luck.

Thanks cyclopathic: plenty of food for thought. Much appreciated

Hmmm, never experienced it myself.
But I've never had Intiminators on a bike over 150kg.
Going to pull the ones off my TT350 and try them on the Transalp sometime though.

After posting above about the 1mm bypass hole, and Cyclopathic's excellent advice notwithstanding, I contacted Jon at Ricor to ask about the possibility of purchasing just a predrilled central bolt. Jon came straight back to me, and offered to send me a complete replacement pair of Intiminators, if I would cover the cost of shipping to UK. I did, he did, and they're here.

Now that is what I call top notch customer service.

I knew I loved those folks for good reason.
They have been very helpful to me on my purchases.