TPS and more mapping stuff (studdering)

[OB_Tweaked]

*** Cross posted to modifications section too ***
So, I just had a Yosh duplex RS3 installed (race baffle). I would normally do all this myself, but with FI, I just took a seat. They adjusted the TPS and set the remapped the stock box at +5,+10,+5 with a Yosh box. I now have the following problems:
1) It doesn't like small throttle openings either taking off in 1st or transitioning throttle on/off in any gear. It has a pronounced hesitation or studder. Seems worse as the bike warms up.
2) It seems fat at idle. Its not crisp and blipping the throttle a couple of times will send the RPMs below 1k, then it will recover (rich on carbed bikes).
The tuner doesn't notice the problem, but I have a finely calibrated seat in my pants;-) They had said they set the TPS at 11 o'clock whatever that means? So, I checked the TPS as outlined here and it looks right (-C00). Can it be slightly off and the indicator still be right? The indicator doesn't move up until somewhere around 1750rpm. Anyhow, doing this I stumbled onto something. With the connector jumpered to check the TPS the idle problem (#2) goes away! As soon as I apply the jumper, the bike idles up a bit. I did all this with the bike at temp, on a stand, in neutral (of course). The throttle response is crisper and it never goes below idle speed (1100) when blipping. Now, what exactly does this jumpering do? Maybe a mapping default? Can I ride it like this (I'd like to see if problem #1 goes away)? HELP!

 

[OB_THE MOTORHEAD]

the tps setting is correct.try 0+5+5.or you got blockage in your fuel screens which became magnified by pipe installation.i had one do it to me last year.and mine did the same after i mod.my airbox.so anything that can alter fuel demand will aggravate this.and remapping will not fix,because if it cannot flow the neccesary volume of fuel nothing will change it but fixing the flow restriction.

 

[OB_Tangram]

Just had Stage 1 Yoshi Cams, airbox mod and Yoshi RS3 race system installed too. Had exactly the same problems. Although the first go at remapping using the Yoshi box to richen up the fuel mixture was good, I found that using the PC2 was better. Working with Richard Albans (TTS Silverstone) we managed an extra couple of HP over the yosh re-map, and cleaned up all but two the humps and bumps that we created by mucking about with the engine in the first place. On the dyno, we could see the dip in the linear progression of power at the 3000rpm mark, but managed to minimise the problem by tweaking the mixture. Post 3500 is now smooth as silk and the 2500 to 3500 dip is much reduced. Like you however, between idle and 2500 is where the problem lies.

Having played with the mix, I've managed to get everything very close to perfect appart from idle itself and a very slight hickup at about 2250rpm. This happened pre-tune too, but is now much reduced and only appears when I go from a trailed to nailed throttle in first or second. I'll get this one solved with more map tweaking. The idle is mixture related I feel, but I don't think it's a setup issue as such. Like 'The Motorhead', I've come to the conclusion that it's caused by a fuel blockage not an EFI map problem. Suzuki themselves have sent me a letter discussing problems with the fuel filter, so I'm going to try a third party filter to see if that gets the extra flow. When the engine is cold or warm, there is no problem. Only when the engine is very hot does it become a major pain. If the fuel filter works, I'll let you know. If you want a copy of the PC2 map I'm using, just give me a yell and I'll email a copy for you to try.

 

[OB_Gary]

That 11:00 setting has nothing to do with the TPS. Sounds like the TPS is correct. the 11:00 is the Yosh box setting for the low speed or "Off Idle" setting. Pretty much what the Pilot Jet does on a carbed bike. This adjustment is pretty sensitive. Try having them set it to 12:00 (Zero) setting and see how it feels.

 

[OB_Tweaked]

Thanks Gary! I thought the Yosh box only had three settings. So we have an idle setting, then a low, a mid and a high correct? I understand the low/mid/high to be -15 to +15 with increments of 5. What are the possible idle settings? Is there anyone else running my setup that wants to share their Yosh remap settings? What does Yosh recommend for this config (I'll call them Mon anyhow)?
Anyone have any ideas on the second half of my post as to why the TPS jumper changes the idle? And whether or not I can ride it like this?
Thanks again everyone...

 

[OB_Gary]

Unless Yosh has changed something, the box goes from -10 to +10. That is real strange about the "Dealer Mode" causing the idle to jump. Has the throttle bodies been synched lately?

Here is a photo of one of my my Yosh boxes.

http://www.tl1000.com/yafms/afms_4.jpg

As you can see, the Low Speed has a lot of possibilities. There are no "Click" for the low speed.

 

[OB_Gary]

Well, if you want to be "Specific", it's

TPS, then balance, then recheck the TPS.

Let me know what happens.

 

[OB_Tweaked]

Thanks for the box photo (no pun indended). My mistake on the ranges -- I remember now that they said the adj range was 20. So there are no clicks on the slow speed setting numbers (analog/rheostat)? If I have to keep driving down to the dealer for adj, I might invest in a Yosh or PCII box. Good source?
The dealer supposedly synced the throttle bodies and then adj the TPS (they were specific about the order which gave me confidence). I verified again that jumpering the connector to get the TPS reading (instead of the clock) does change the idle. It idles up by 50 to 100 rpm and is noticeably crisper which is what I want (hopefully it fixes the on/off hiccup problem too). Maybe they cancel out any slow speed settings when checking the TPS? Curious.

 

[OB_Tweaked007]

I had them make the following settings with the Yosh box: 0(noon) for slow speed and then +5 across the board for low/mid/high. The idle is much improved, but it still has the on/off bog (feels like a studder because is bogs/loads then jumps when it clears). Its worse in 1st and 2nd gear though I'd still swear its rich. Its just so hard to be sure. I'd like to try 0,+5,+5 next and I will if I get a sunny day soon to get over to the dealer. In the meantime, I've decided to get a PC2. After a bit of searching, one is on the way to arrive on Thursday. Past that, I'll have to dig in and do the screen and tb check (yuck). Again, I'll keep everyone posted either way.
:-0 Anyone got a good stock bike + Yosh Duplex Race PC2 map they want to share? I'll start with the one off the DynoJet site and go from there otherwise.
Will I have to adj the TPS again after adding the PC2 (or is that a rumor)?

 

[OB_KawAbuser]

Looks like the UK and US ecm is a differant part as you guys in the UK endorse the "PINK WIRE" cut mod.

I have RS3 race, stage 1 cam, stopck airbox with a BMC

Idle at 11:30
-5 -5 -5,

these settings were learned on a dyno

 

[Guest]

I'm preparing to spring for those cams buser, will I be happy?