TPS/STV/FI...adjusting issues, possible HOWTO in the future

Hello everyone, I need some help from you, hopefully there'll be someone among you who will know better than the people I asked so far (motomechanics and people on other forums, etc.).
I apologise if it's gonna be longer reading, but I'm not really good at writing it short, but I will do my best.

The bike is SV650S K3 (2003)

My TARGET is pretty simple, I want my bike to be at 100% working condition with no issues or even quirks.
My biggest gripe is the infamous jerkiness/twitchiness AND Fast Idle not working properly. Now, I did some standard, well-known steps to improve it, first thing was proper TB synchronization, TPS adjustment and whole new chain set with sprockets. All this helped to some extent, but it's just 50% of the way where it should be.
Regarding the Fast Idle, it was not working at all, meaning when I started the bike when it was dead cold, RPM were always at hot idle (1300+-) and struggled to keep running with some hiccups for a few seconds. I tried to adjust the Fast Idle screw and it helped, RPM were at 2100 for next two starts, but now it does not work again for some reason. While I was adjusting FI and TPS, I noticed that Secondary Throttle Valves (STV) seems to be out of sync (different height/angle and it never got fully open).

That's where I got lost. My final goal is to have:
Throttle Bodies (TB) synced
STV (Secondary Throttle Valves) synced and properly adjusted
Throttle Position Sensor (TPS) properly adjusted
Secondary Throttle Position Sensor(STPS) properly adjusted
Fast Idle (FI) properly adjusted and working

At this time, it's only TB and TPS adjusted, the rest is not working (FI) or is terribly misadjusted (STV).

Now, I want all the above working at the same time obviously, I've read through many manuals and forum advices, but it didn't get me very far, some are not really clear, some are for different bikes (SV1000), some are counterfeiting with the others and therefore not trustworthy.
What I'd need is complex and thorough instructions, how to do all the above and what to do first and what to do next, so the rest won't get out of sync/misadjusted again in the process, as some mechanics told me it will if I don't do it properly.

I know I ask for a lot of work, but I was thinking, if we got heads together and I would be able to follow instructions and do it, I could take pictures and make a proper step-by-step sticky thread, that I'm sure would help many SV riders here and it would be on at least the same level of helpfulness as the TPS thread is for most of us, not to mention it would improve the quality of our SVlife

Huge THANK YOU to everyone who will contribute to this in any way.

[Bibio]

you will never fully get rid of jerkyness on a v-twin, i'm afraid its the name of the game. learn proper throttle control instead. a v-twin requires a lot of clutch control/slipping at low speed manoeuvrers to keep the revs high. once you master low speed manoeuvrer control then you will master the jerkyness.

DO NOT MESS WITH THE STPS. this is controlled via the CDI to correct the air flow. getting this wrong can mess with the fuel mixture. only and only adjust the STPS if you have the correct tools (SDS, DMM) and you know what you are doing.

the first thing to be done is a full service including the spark plugs and air filter. once this has been done then set the idle speed to around 1300rpm at fully warmed up.

Throttle Body sync. you must adjust the idle speed as you adjust the sync. adjust the sync then let settle then adjust the idle speed and repeat till its done. dont go mad looking for perfection as you will never achieve it. in the grand scheme of things its not that important and as long as its 'near enough'.

NOTE: on twin spark bikes K7> you must use an SDS tool, no iffs no butts as you need to lock the air idle valve down. the K7> twin spark is also set via the bypass screws and NOT the usual butterfly adjustment screw.

last thing to be done is the TPS. do not use a DMM for setting the TPS. you need to do this via the dealer mode line markings on the instrument cluster. the TPS is exactly what it says a Throttle Position Sensor. to set this for least jerkyness you need to set it so the line moves the moment the throttle is turned (excluding slack in the cables). setting the TPS in the manner i have suggested severely reduces engine braking but doing so smooths most of the low speed jerkiness.

[Bibio]

something i forgot to mention is partial/blocked injector mantles. its not common but it does happen. IIR muzikill on this forum had the problem and like you tried everything until he got the injectors serviced which cured the problem instantly.

BTW. motorcycles need maintenance, things go wrong, you can never make a one time adjustment, its all continual servicing. yes some adjustments or servicing items need not be done for a long time but they will need done.

the biggest investment you can make for any motorcycle is tools and the knowledge to be able to use them. there are some specialist tools that you may only use every 30k miles so if not willing to invest in them then take your bike to someone who does have them when the time comes.

Thanks for the reply.

I know some jerkiness is normal with this engine, but what I'm experiencing is definitely not normal.
Just FYI: valves are OK, TBs are synced, TPS is adjusted.
Only thing I noticed, as I said in the original post, is that Fast Idle is not working at all and Secondary throttle valves seems to be out of sync (every valve is opening differently and the opening itself seems weird too).

That is why I want to have secondary valves synchronized so it opens the same at the same angle and STV sensor adjusted too, so it opens the valves properly. Of course, working Fast Idle would be great.

Btw, not sure what you mean by STPS, but TPS is adjusted and CAN be adjusted pretty easily, same goes for STV sensor (STVS), according to manual.

[Bibio]

my mistake, i meant the STP. with regards to the STV's (secondary throttle valves, top butterflies) yes they do flutter under normal running.

essentially there are 3 sensors on the TB's. the TPS (throttle position sensor), STP (secondary throttle position) and the STVA (secondary throttle valve actuator).

the TPS is the main sensor that senses the position of your throttle.
the STP is to control the air intake and is auto controlled via the CDI (do not touch this as its factory set and requires careful setting up).
the STVA is essentially a choke but automatic and again is controlled by the CDI but is also linked to the temp sensor. only adjust this if you know the temp sensor is working correctly.

problems associated with the STVA are usually the fault of a duff temp sensor. if the temp sensor locks closed then the bike will not idle properly cold as its not sending the correct temp reading to the CDI to tell it to activate the STVA. visa versa to above when hot.

Alright, that shines a little bit more on the issue.
However, it's still not fully clear.

STP = is it that sensor for secondary throttle valves? Service manual says you CAN adjust it, says nothing about being CDI controlled. Page 244, STP sensor adjustment.
This also says you can adjust it: http://www.sv-portal.com/forums/5-tw...djustment.html
However, it does not say anything about "syncing" the butterflies (secondary plates).

The info about temp sensor is good, however I'm not sure which temp sensor you mean - the one that senses cooling liquid temperature and is also shown on the dashboard display? I think that one works okay, because the temp is shown correctly, also the ventilators are turned on when it reaches approx. 102 Celsius.
Just FYI, one mechanic exchanged one temperature sensor that was faulty two weeks ago, because the ventilator never turned on, after the switch, it's working fine.
Just so you know, I don't know how many temperature sensors are there, so I'm trying to tell you what works and what I see, if that's what you were talking about.

Last thing, nobody yet commented on the out of whack secondary throttle valves (the plates itselves) and the fact it does open fully and that every plate is in different position (ie one plate is horizontal, where as the second is half open). Can you shed some light on this, if you know anything about it?

[Bibio]

lets get one thing straight. the workshop manual is just that, its a manual intended as a reference for technicians who suzuki assume know what they are doing therefore they omit a lot of warnings. just because the manual states that you can adjust something does not necessarily mean that you should without diagnosing the problem first.

as far as i'm aware there are two temp sensors, one on the radiator to engage the cooling fan and the other is on the thermostat housing. its the one on the thermostat housing that goes dud.

And which sensor reports the temperature on the display? If I'm correct it's the one in thermostat.
If yes, it should be working fine, considering it shows the temperature correctly.

[Bibio]

Originally Posted by Riotstarterr

And which sensor reports the temperature on the display? If I'm correct it's the one in thermostat.
If yes, it should be working fine, considering it shows the temperature correctly.

thats an assumption. i have just checked the workshop manual and i was wrong about it being a simple switch. the sensor can read different values at different temperatures. if these values are wrong the it sends different data to the CDI. you will still get a temp reading on the display.

Ok, I will think about replacing it.

Anyway, I'm gonna remove the STV plates completely, without removing anything else. Then I will install Gipro ATRE on monday and I'll see how it goes.