A sprocket change (114link) and what I did with YSS "ride height" rear shock

[rideontt]

I have to thank Mr.Raja who lent me the YSS shock (with ride height) to satisfy my curiosity about ride height device benefits



removed to see what is the overall length (27mm)

 

[rideontt]

the height range for every half-turn value goes as follows: 9.3>8.8>8.3>7.8>7.3>6.8>6.3>5.8>5.3 etc. (at the lowest setting possible measured distance is 2.3mm as shown above positions in the picture)
>at 8.3 mm height the shock length is approx 330 MM thats 10mm longer than the OEM shock at step no 9 on max preload.
it is a significant gain in ride height.

 

[rideontt]

to show how 390 is with after-market shock(no ride-height option) at speed from

Spoiler: guess the speed

80kmph /50mph upwards

on continues S curv & Z zig zag turn that ends with a right yeah right curves are my challenge .
Video from Kevin Camroon:

It is a problem for me indeed since steering/turn 390 is possible when I muscle it in and by that time I have missed the turn-in point and also feel that I am getting 'pushed' when I am off the throttle to correct the late turn-in carrying momentum.

what i like the feeling when riding the 125 its so simple to flick it from side to side its fun a exact opposite of 390 with upgraded suspension (without ride height devise for rear shock)

 

[rideontt]

the Stock/OE is 15Tooth engine /45Tooth wheel sprocket with 112links
new
15Tooth engine sprocket /46Tooth wheel sprocket with 114links lengthwise 10mm longer than OE (un installed chain length 907mm length)

I am using this(new) to accommodate the 46Tooth & 47Tooth(soon) which is not possible with 112 link OE chain until it's worn significantly

with the above sprocket (chain worn after 9000km/ 5500miles)the handling at curves on the handle bars is tight/heavy
so flicking it is easy when the throttle is off and waiting out till the road is straight, if/when i throttle earlier motorcycle would exit wide. The acceleration is simply awesome when riding alone (15T/46T 112links)

 

[rideontt]

the wheelbase increased from 1365mm to 1370mm using 15T/46T 114links.

ride height at 6.3mm used

View attachment 7335

the height range for every half-turn value goes as follows: 9.3>8.8>8.3>7.8>7.3>6.8>6.3>5.8>5.3 etc. (at the lowest setting possible measured distance is 2.3mm as shown above positions in the picture)
>at 8.3 mm height the shock length is approx 330 MM thats 10mm longer than the OEM shock at step no 9 on max preload.
it is a significant gain in ride height.

when dialling in/adding Preload to Rear shock height increases this affects freeSag(lesser) and when the preload is reduced the ride height(reduced) and freeSag (increase).
so
with"Ride height device" lengthens the rear shock height & does not affect the freeSag/dead zone
this
affects the front of the motorcycle with changing/reducing the trail value and probably rake angle too. eg; Trail nos if 110mm stock changed to 105mm these are guesstimate values.

6.3 mm longer ride height and '15-18mm of freeSag/dead zone' the motorcycle rides wonderfully and can carry momentum into a turn with minimal bar force to lean the motorcycle.

 

[rideontt]

Other observations:
> Since the ride height increased and after a 40 min ride stopped for 5min when i checked the oil level shows above full Previously with "shock factory

Spoiler: Shock factory rear shock without ride height device

" https://www.rc390-forum.com/threads/m-shock-from-shock-factory-mike-capon.3870/#post-35655

oil level always been between the minimum and full mark after service or just on the low mark at times

> The handlebars/ Front end on my hand iz a lot easier to initiate the lean, with a pillion it is easssssyyyyyy to lean

>With the long wheelbase (15T/46T 114 links) pivoting the motorcycle using the side stand or lifting the rear slightly to move from a tight parking slot is now too heavy its like the "36th chamber Shaolin:

a visual feel for reference, Like the end of the video me hope would be able to do same

> The fork travel used is between 40mm and 55mm for local rides

Racetech fork springs & learning

these are 8.5Nmm or 48lbs/inch, free height is 315mm. OD ; is 34.10-34.45 mm for side A and 36.6 to 36.80 sideB. >the recommendation is 10mm of preload from Race Tech a good point >>for Mortals !!! thoughts goes like following; OEM spring is 345mm -315mm= 30mm +10mm preload :rolleyes:+10mm...

www.rc390-forum.com

> With a long wheelbase the pillion is also very comfortable; reduction in the pillion sliding towards the front during braking & a significant reduction in the pillion helmet clanking & when accelerating and less force to grab me shoulder when being as delicate as possible with throttle input was noticed.

> On braking with the rear brake only I can feel the rear wheel helping a lot more to slow the motorcycle down which was true with the OEM wheelbase but now it is a lot more ahhh tractable & or I can feel it much more with less effort from the foot pedal.

> SO in traffic with a crowd of motorcyclists Doing U-turns i feel so comfortable that I am "meh" me can dodge them with less effort and can lean more if required & grin that now I am almost equal to a commuter motorcycle in terms of its agility

> When ride height was increased, I noticed that the chain slack/sag increased, I Had to re-adjust

> On its side stand the motorcycle leans a lot more than normal so I keep adding stones underneath the stand to reduce the lean when parking

> The swing arm having a noticeable droop angle is rather nice and odd at the same time when it's parked
> Trail braking to keep the motorcycle leaned or in a line now requires lesser input/and sometimes no input for street use
>Now it's possible to use the throttle smoothly at the exit or certain curves earlier without worry

with these positives, I wonder if the motorcycle was limited because of rear shock dimensions & sprocket set up?!*#.

 

[rideontt]

Fluff or Goof to set YSS shock having; Threaded pre-load>Rebound damping& Ride height​

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situation1​

Flawed expectation from Operators: a setup that suits rider x*(above 80Kg/177lb) weight & pillion light Y*(56Kg/123lbs) and heavy Y1*(90kgs/200lbs) with no change in preload ride to be comfortable n soft, my mind[ Wrong expectation] ​

​

Situation2​

when getting a shock that has Ride height and not trying it

situation3​

Dialling in preload without freeSag/deadzone' leads to getting all the road undulation on the body(the rider/also pillion )​

​

situation4​

Ride Height lengthened to 20MM; makes the motorcycle too twitchy eg; move the head the motorcycle would want to fall on that spot (it is like I am spun on a bar stool and then I am asked to walk up to the end of a room ) some like this kind of set up & its okay​

Ride Height also Helps with how the Front end feels on a turn entry and exit/ there is a gain in ground clearance & visually a descending swing arm angle towards the rear tyre. Preload also does the same thing(increases/decreases ride height but it changes the sag values too)

Rebound to control how controlled (slow) the shock returns

The pre-load when dialled down/reduced I get more freesag when I am riding solo and I add more preload when there is a passenger to carry reduced freesag values.

 

[rideontt]

So this is an observation on the OEM ride height of a Motorcycle the above is the front wheel showing how much unused tyre is available (10-15mm)




this is the rear tyre of a motorcycle with OEM ride height and how much-unused tyre is available (5-8mm).

the weight transfers towards the rear on acceleration and just enough towards the front.


tyres are TVS EUROGRIP Pro Torq Extreme a soft carcass very stiff bead and stiff side wall as well. I guess these be available in other parts of the globe in arriving few years (the tyre is the one on the new Aprillia RS452 launched recently)




Observation KTM after ride height increased (picture is of rear tyre) showing the unused section of tyre 10-17mm

the ride height keeps the weight on the front reducing the rear-biased weight transfer, the front wheel is weighted so the motorcycle holds its line and it is easy on my hands which now hold the bars lightly (15T/46T 114links)



The picture is of the front tyre after the ride height increased showing the unused tyre of 10-13mm

Tyres are TVS Protorq Sport slightly more firmer carcass for a better feel from the rear.

 

[rideontt]

Ride height 7.3 mm

Counter steer and how the handlebar turns back from initiating the turn: this is not felt on 390 including with upgraded shock from "Shock Factory" (my opinion).

On YSS it is very much more noticeable at 7.3mm ride height. I have also added 1.5 turns of preload (to accommodate a passenger) and 5 more added on 'rebound' clicks ( there is a problem here).

the thing is the shock has lost its "nitrogen gas which leaked" Clickers are not easy to feel it's like turning a tap so this is a common occurrence on shock (I thought it had an independent free gas separator piston) and requires yearly service of replacing the seal kit n new shock oil 2.5w type / also the YSS shocks has leaking shock oil that also indicates service due< the shortcoming on YSS on longevity usage it's few years old >

"Shock Factory its clickers still functioning and the clickers work well to date just that I did not choose the ride height device still erks.

Other observations
another thing now happening is the 'start switch' won't operate when the motorcycle is left as is for a few days(on the paddock stand) when I remove the paddock stand lay it on the side stand and attempt to start there is no response

I checked the light>horn >indicator > engine kill switch all worked but no response on the start switch.

>>>> my wild guess is the Banking sensor might be getting enough tilt for it to activate since the rear has gained height<<<< any advice? the sensor is new
when the motorcycle is running for the day there is no issue at all.

The ride is amazing with a pillion with 7.3mm ride height (1mm more than previous) the front end on executing counter steer is more evident/noticeable and also carries momentum onto a turn and feels like i am using a lesser lean angle (control is easy)
the pendulum effect when the pillion leans on the opposite side is no more, my head is centre of the motorcycle so there by the pillion is comfortable

 

[rideontt]

Ride height 7.3 mm

Counter steer and how the handlebar turns back from initiating the turn: this is not felt on 390 including with upgraded shock from "Shock Factory" (my opinion).

On YSS it is very much more noticeable at 7.3mm ride height. I have also added 1.5 turns of preload (to accommodate a passenger) and 5 more added on 'rebound' clicks ( there is a problem here).

the thing is the shock has lost its "nitrogen gas which leaked" Clickers are not easy to feel it's like turning a tap so this is a common occurrence on shock (I thought it had an independent free gas separator piston) and requires yearly service of replacing the seal kit n new shock oil 2.5w type / also the YSS shocks has leaking shock oil that also indicates service due< the shortcoming on YSS on longevity usage it's few years old >

"Shock Factory its clickers still functioning and the clickers work well to date just that I did not choose the ride height device still erks.

Other observations
another thing now happening is the 'start switch' won't operate when the motorcycle is left as is for a few days(on the paddock stand) when I remove the paddock stand lay it on the side stand and attempt to start there is no response

I checked the light>horn >indicator > engine kill switch all worked but no response on the start switch.

>>>> my wild guess is the Banking sensor might be getting enough tilt for it to activate since the rear has gained height<<<< any advice? the sensor is new
when the motorcycle is running for the day there is no issue at all.

The ride is amazing with a pillion with 7.3mm ride height (1mm more than previous) the front end on executing counter steer is more evident/noticeable and also carries momentum onto a turn and feels like i am using a lesser lean angle (control is easy)
the pendulum effect when the pillion leans on the opposite side is no more, my head is centre of the motorcycle so there by the pillion is comfortable

the position of the rear axel with 114Links chain/15Tooth engine sprocket/46tooth rear sprocket) I have reduced the preload by -1 turn for solo riding > Now the motorcycle is agile and flickable since the static sag has increased, previously i was struggling (+1.5 turns preload) .