This is the 2nd gen RC200.
Looks big because the cats has been remove.

workshop looks like it does suspension rebuilds....... given the tools.. hahahaha

bike is at 40,000km when i changed the timing chain.
still within tolerance limit but gatal tangan since i feel that it's quite near its maximum limit. sounding kinda noisy for my ear.


and no idea if the fuel system cleaner is working or not but my intake valves all look like this.
clean with absolutely no deposit and no oil trace or goo.

so i'm guessing it might help a bit?
it's not really expensive anyway so i put it in maybe like once a month or once every few month.

yup, mostly focus on car suspension.
once in a blue moon, somebody send in motorcycle shock.

I drop the front or raised the fork tube.
To gain better turn in or aglity.
I be damned, less fatigue trying to manhandle the bike through corners or tight manuvers.
Wish I had done earlier, I am a bit wee smaller frame compare to other riders.

I'm guessing KTM had those lines for people to adjust the bike geometry to their liking.
Doesn't feel nervous at higher speed.

Just installed a pair of IRC S99, good lord what was I missing. The tyres feel much more pliant than the Corsa S123 with the softer compound and taller sidewall.

I used to feel a lot of vibration and discomfort coming from the S123 with road undulations, even before being able to test the tyre grip I am already feeling money well spent.

Condition of the Corsa S123 after 7000km of mostly city rides:



Looks like it still has 15000km in it... Credit where it's due it's a long lasting touring tyre but I can't imagine staying with it for another 2-3 years. It feels heavy and clumsy coming out of corners and vibrates a lot.

This post has been edited by JustForFun: Aug 15 2025, 09:02 PM

Removed more stuff from the v1k

Namely the phone holder coz i wanna keep it as it was rm100+ n has wireless charging ... Also removed my autogate remote from the bike.

N also swapped out my dual usb voltmeter thing for a single usb voltmeter which has been in storage since 2018.

[attachmentid=11517342]


Attached thumbnail(s)

Yes, that's one way to do it. When you drop the front you change the overall geometry (rake and trail) and weight distribution of the bike. The other way is to stiffen or raise the rear up

My 800nk has the same issue of too much head shake powering out of corners. It's partly due to the factory geometry and how the riding ergonomics sits the rider fairly upright.

Dropping the front even a small amount (12mm) and reducing rear rider sag 5mm and slowing down rear rebound slightly
was all it took to sort the front end stability out.



That said, dropping the fronts would and should make high speed stability worst. in my case, the stiffer rear is probably the main contributor to reduce rear shift weight transfer and the head shake (bike comes with a factory steering damper)

The s123 lasts almost forever. I have over 20k on my rear (lost track ...it's been that long) and it's like half done. No vibration on my 150/60 though. Your tyre/ wheel balanced properly?

My S123 tyre change was unplanned as I had a blowout a month into my ownership, so I didn’t know better to request for tyre balancing, but that is unlikely the reason for the vibrations as they are largely felt when I go through bad roads — which is daily because I commute on the absolutely dogshit Federal motorcycle lane (glad they announced a 20 million budget this year for the upkeep). I could tell immediately after that my bike felt slower and clumsier, because the stock Ninja/Z400 come with good Dunlop tyres that you could even do track days with, so it was definitely a downgrade.

I’ve actually been reading up on tyre discussions since February, and only pulled the trigger this month. Across the Ninja 400, Duke 390, and 450SR forums, I’ve noticed a common trend: owners swap the stock 150 rear for a 140 and report noticeably better handling. It feels like there’s a consensus that most 200–400cc bikes coming with the stock 150 rear tyre would do better with a 140, so I was eager to try it out despite the long life left on my S123.

This post has been edited by JustForFun: Aug 23 2025, 03:24 PM

esp true if with cross ply tyres

Honestly, I dont see how a 140 section tyre can make the bike handle better (i read that as more agile) than a 150 section tyre, all things being equal. The physics dont support that.


a 140, usually have a taller profile being 70, which a 150 is 60. Usually, the 150/60 will have a more steeper/sharper profile and by that itself, would be more agile turning side to side.

If you say the 140/70 would have more straight line grip, then i can see the reasoning behind that, the 140/70's flatter profile has the bigger contact patch at the expense of maximum lean angle.


The difference is probably due to the rubber compound, construction method that contributes more to the more agile feeling as would just the profile width. As Alexi has alluded to, the difference can also be attributed to radial or Bias ply tyre construction. Radial tyres tend to be lighter than the equivalent bias ply tyre.


I had 190/50 and 180/55 (stock size) on my NK before. the 190 is without doubt the more agile tyre , but I am limited by foot peg clearance leaving about 10mm of chicken strips at peg limit. The stock 180 has no chicken strips and is more secure feeling. But agility, the 190 is better. Both were Michelin Road 6 tyres.

The 190 however does afford some additional leaning headroom in the "oh shit" situations you go in too hot in a corner and need that extra lean angle to make the corner. Even if it means scraping your foot pegs. and FWIW, those peg feelers serve to tell you have much tyre thread is left in a lean.

This post has been edited by jaycee1: Aug 25 2025, 11:17 AM

Since the 140 here refers to width, shouldn't it mean a less narrow and thus a more V-shaped profile with less contact patch when running straight? Basically going from U -> V

The arguments you would see most often for a 140 against 150:
1) Narrower, more V-shaped profile so you can flick your bike faster
2) Less contact patch when you lean = less rolling resistance (and less grip of course)
3) The taller profile ensures you have more leaning angle to work with in a corner

My real world experience has been improved handling, but that's probably more because the S123 isn't designed for good handling.

This post has been edited by JustForFun: Aug 25 2025, 05:12 PM

Yes, all things being equal.

But you forgot that the profile height also contributes to how sharp the the tyre can be.

Most 140 tyre are 70 height, while 150 tyre are 60. , unless you ride and ADV with 150/70 profile tyres. As with anything, this is just generalization as manufacturer can make the profile as flat or as steep as they want for any given profile.

Another reason why some switch to 140 from 150 is 150 section tyres were actually more rare and expensive a few years ago. The 140s are more common as they are usually used on 250cc bikes. The 400cc class that uses the 150 section tyres only burst out in popularity maybe 5 years ago.

This post has been edited by jaycee1: Aug 26 2025, 08:39 AM

First consideration is rim size. Starting from R25, to the Ninja 400, RC390 and 450SR mentioned, I believe all have 4 inch width rear rim. Options are 140/70 and 150/60.




Note: this is a general chart, some tyre models may vary

Key takeaway from fitment guides:
1. For the same size, going lower on the aspect ration (AR), from 80 to 70, a larger rim width is recommended
2. Bias ply vs radial tyres can have different fitment guides (example below)



From Metzeler's book, a 140/70 is recommended for 3.75; whereas the 150/60 for a 4.25. Both will work on 4 inch rims, just the 140/70 will "expand" a little, while the 150/60 "pinched" a little. One way to do this, is to measure the tyre bead's distance from edge to edge before they are mounted.

My personal preference:
- high profile tyres such as bias ply, is better 'expanded' but can be pinched, because of the construction, either way is fine
- lower profile radial tyres should try avoid over-pinching because it affects the stress distribution at the radial belts which spans radially around the tyre

This post has been edited by alexei: Aug 26 2025, 10:28 AM

heres a before n after of what i did to my bike yesterday

BEFORE


AFTER

Congrats on your new bike

How does it feel compared to the old versys?

congrats man!!

so far only ridden 80km... at max 4k rpm.

even that feels like a pretty big upgrade over the peanut.

there are things i miss on the peanut but they are minor and just a matter of getting used to it

Yes, thats right. Which is why on a 150/60 the tyre will end up slightly more steep profile because it gets pinched. But usually 0.5" difference in wheel width wont make too much of a difference. Tyre manufacturer typically gives a range of wheel widths. That goes without saying that each manufacturer will have different specs.

And as for tyre stresses go, unless you are tracking it, the 250s and 400s aren't making enough power anyway to over stress the belts. The 150s usually have stronger belts and higher load rating than the 140s.