Assistance requested- setup notes

[theDoktor]

I am putting together baseline setup notes for my recently received, low mileage and completely stock, 2022 TS660. Tomorrow I will be getting baseline sag readings on the suspension with a Motool Slacker v4. In entering data into the app that accompanies the tool, I quickly discovered needed data that neither the Owners Manual nor the Triumph website has. I suspect much of the missing information is in the Service Manual. but have not yet signed-up for the subscription. (And not looking forward to that either. I'd just rather buy the manual and be done with it!) Anyway, might any of you who might have access to the data I need be willing to send it to me?
What I am looking for is the following:
Front Suspension:
Spring Rate
Static Preload
Fork oil brand and weight
Fork oil height installed

Rear Suspension:
Spring rate(s) and spring lengths, uncompressed
Shock fluid brand, fluid weight

Gearing:
Confirm number of teeth on REAR sprocket (only)

Based on 150mm of suspension travel front & rear, my baseline target sag settings appear to be:
Static: 15mm
Rider or Dynamic: 45mm
It will be interesting to see how those numbers match up to the settings in the Owners Manual.

Thanks for the help and input. I'll be sharing my findings with everyone in the near future

[mrlm]

I had a look and I cannot see all that info in the service manual.

You may have issues tuning the suspension as only the rear has preload. No damping adjusters anywhere. It has a rising rate spring which will cause more sag than you would expect for the spring rate, and also has a linkage which may also be rising rate.

The general consensus appears to be that the spring is too soft for heavier riders and the rising rate doesn't help or just confuses people. I also find the rebound under damped occasionally.

45/150 = 30% which is exactly the sag I would expect for long travel. I occasionally ride mid preload for a bit sharper steering but also change to min solo and max with pillion. Not sure exactly how much this alters the sag though.

[theDoktor]

Thank you for searching for that info- good to know. I'll be heading to my suspension tuner next week to see if he has any sources & what direction to go. He happens to be an Olhins dealer too.

I'm aware of the spring issue with the shock. It's actually a dual-rate spring (actually a pair of springs- a soft initial spring and a firmer follow-up spring). And I know that the softer initial spring is going to throw the sag readings off. I hope to get enough data so that I can graph the full range of preload clicker settings vs. measured sag, both for Static and Dynamic sag. I suspect the graphing will clearly show the change-over in spring rates. Of course, my Dynamic sag numbers will only apply to my specific fully-geared riding weight...

Ultimately, I plan to get a replacement shock with a remote preload adjuster and both compression and rebound adjusters that has either a progressive rate or (preferably) a single-rate spring. The linkage kinda pushes me more towards a single-rate spring.

The forks seem to be pretty good as-is, so messing with them is down the road. I was recently advised by Andreani USA that they just came out with a cartridge kit for the TS660. They've had a kit for the Trident for a while. It would be nice to have some adjustability in the forks. Right now, the only things to play with is oil viscosity and oil level. BTW, there are HUGE tested differences in actual vs. stated viscosity between the various brands. See the following: https://transmoto.com.au/comparative-oil-weights-table/ You want to be looking closely at the two following test values for whatever brand fork oil you choose: Viscosity @ 40ºC, cSt (ASTM D445) and Viscosity Index (VI) (ASTM D2270). I suggest you pick a trusted brand and stick with it. I like Maxima Racing (not the regular Maxima stuff) and Amsoil

[theDoktor]

A brief update. I've completed checking the STATIC sag (bike weight alone) at the rear for all 30 preload stops. I haven't had time to graph the results yet, but the initial setting at full soft was just 12mm. That's a bit less than I anticipated, but this IS a sporty bike, so firmer settings should be anticipated. The sag settings rapidly reduced as the clicks of preload increased. By 6 clicks, preload dropped to 8mm. By 10 clicks, it had dropped to 6mm. It hit 3mm at 15 clicks (half of the preload adjustment range); by 16 clicks it had pretty much stabilized at 2mm of sag. It remained at that sag dimension until the clicks of preload maxed-out.

[theDoktor]

Slap my hand, but I goofed-off and took a nice little ride yesterday rather than getting the promised rear sag data. However, I just finished it and here it is. Hope it is useful.

A brief descriptive summary: I found that for a fully-geared-up rider with a dressed weight of 198#, the rear pre-load sweet spot seems to be either 7 or 8 clicks of preload. This results on a sag reading of 38mm- right at the low end of my target range of 45-38mm. I couldn't get to 45mm even at full soft on the adjuster- it read 42mm. At 8 clicks, the ride is firm, but smooth. handling is good and well-controlled. Even on an easy introductory ride, I am able to use the entire rear tire tread down to the row of tread depth holes around the tire tread outer edge

[mrlm]

Do you find that a few clicks at the start don't do anything?  For me from fully unwound it is a very small partial rotation into the first click, then almost three easy clicks as I feel resistance just at the fourth. From this point each click produces an seemingly equal linear change at preload ring, although the change in sag may not be linear due to the linkage etc. This probably just means the twist adjuster has more range than the preload ring but if others don't have the same experience mine may need adjusting to achieve full preload. It also means when you are working out the preload clicks / sag settings you should probably disregarding those first clicks and count from the first resistance.

I realise this is not what you would do with damping, where you measure from fully undone but those work differently and the adjustments are all within range.

[theDoktor]

Originally Posted by mrlm

Do you find that a few clicks at the start don't do anything?  For me from fully unwound it is a very small partial rotation into the first click, then almost three easy clicks as I feel resistance just at the fourth. From this point each click produces an seemingly equal linear change at preload ring, although the change in sag may not be linear due to the linkage etc. This probably just means the twist adjuster has more range than the preload ring but if others don't have the same experience mine may need adjusting to achieve full preload. It also means when you are working out the preload clicks / sag settings you should probably disregarding those first clicks and count from the first resistance.

I realize this is not what you would do with damping, where you measure from fully undone but those work differently and the adjustments are all within range.

My findings with the preload adjuster were simiiar to yours. On my bike, the first turn of the adjuster to the first click was nominally in the range of 3/4-7/8 of a full turn. There was minimal resistance for the first 3-4 clicks/turns, then resistance seemed generally consistent until I got to about 25 clicks or so, where the resistance seemed to increase again. If you look at the first page of my graph to the chart that lists the measured sage values, you'll see that, despite the lack of resistance, there was still a measurable change in sag measurement. This range of adjustment will be more important to the lighter riders out there. Keep in mind that thegraphed values apply to my measured, fully-geared riding weight of 198#. The values will be different for those weighing more or less than me.

[mrlm]

Sorry I completely missed the attachment, then I missed the second page.

I took it apart to give it a clean and inspection as it will never have been done and was corroded on the screw. It works exactly as I thought, there is a smaller piston held in place with a retaining clip and a spung ball with a detent on the adjuster.

The good news is there was no dirt and very little corrosion inside only a tiny amount from the circlip, so you don't need to worry about taking it apart. The bad is you will struggle to put it back together with the ball on the spring, I will have to make a tool to do so.

A circlip holds this piston in place and the free play is the difference between the length piston and the tube up to the retaining clip. As I expected this it not taken up when you sit on the bike therefore those first few clicks are not having any effect on the sag.  So it might be worth redoing your tests a few times and excluding the outlying results.

[theDoktor]

Originally Posted by mrlm

Sorry I completely missed the attachment, then I missed the second page.

I took it apart to give it a clean and inspection as it will never have been done and was corroded on the screw. It works exactly as I thought, there is a smaller piston held in place with a retaining clip and a spung ball with a detent on the adjuster.

The good news is there was no dirt and very little corrosion inside only a tiny amount from the circlip, so you don't need to worry about taking it apart. The bad is you will struggle to put it back together with the ball on the spring, I will have to make a tool to do so.

A circlip holds this piston in place and the free play is the difference between the length piston and the tube up to the retaining clip. As I expected this it not taken up when you sit on the bike therefore those first few clicks are not having any effect on the sag.  So it might be worth redoing your tests a few times and excluding the outlying results.

Thanks for the useful information, but I have no plans to take the OEM preload adjuster apart. I just want to be able to get the OEM shock working the best it can for me, then replace it with a quality after-market unit with both damping adjustment and remote preload adjustment. I need to tweak the preload often enough that the extra cost of the remote adjuster is worth it for me. There's just too much disassembly required to get to the  shock spring adjustment collars in order to make an adjustment on the spring preload.