Triumphrat

I've put a micron can on my bike, a k&n in the airbox, and then the dealer loaded an off road tune for my s4. Seems to run pretty good, but any thing under 4-4.5K RPM seems to make it jerk. The only time this is a problem is when I pull out slow, usually making a turn at a light. I've also noticed that the lower RPMs doesn't have the same pickup that it had w/ the stock can. It feels like its flat or hesitating. I don't have this problem when I take off quick! I've seen stuff about adjusting the CO levels.

What's the deal here? Do I need to have the dealer "tweak" something? Or will this only be solved with an investment in a Tuneboy or Power Commander?

Thanks

Rik

They aren't always the smoothest around the 4K mark. I have a standard can and filter but still get the occasional low speed jerk(!) - I used to just blip the thottle to clear the lump but now find accelerating very lighty and feathering the rear brake works perfect , especially when I'm about the turn into a slow corner.

I expect a Tuneboy/PC can help smooth the lump out a bit but I haven't gone there as I'm not too sure how it might affect the warranty and I have a year left on mine. :???:

Will

The latest version of TuneEdit has a graphing function that lets you look at the codes plotted out against rpm and throttle opening. There is a big dip in timing advance that corresponds to the rpm range that you are fighting with. You can't do anything about it with a PowerCommander, but TuneEdit lets you tune it out. I believe that it is there for EPA reasons- if you worry about pollution, leave it there. What? You don't worry about that when you are on your bike? I am shocked!

Recently, I took the codes that were in my bike and smoothed out all the dips and spikes in both the fueling and timing maps. It seems to have worked, since the bike still runs! The butt dyno is very happy, since the power is more linear now, and any fluff at low speeds is gone. I was also able to lower the idle speed from 1600 to 1400. The codes that I had were not stock to begin with, but the smoothed out maps seem to work a lot better. It seems to be getting better fuel range, too. Friday will be the first track day of the summer, so I won't know how it really works at the top until then, but so far, just smoothing everything out so that the graphs look nice seems to have made a huge difference. If/when the whole Blueflame deal comes through, the bike will go on a dyno for some final tweaking, but for now, it seems to work better than it did.

I don't know what it does to your warranty, but if you are really concerned about it, you can always reload the stock codes. You can get them from the TuneBoy website.

[ This message was edited by: Will on 2004-06-08 12:30 ]

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Will
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So just to clarify....

I probably need a Tuneboy to really tweak it and smooth it out. Right?

Can the dealer make any adjustments other than loading a different tune? I thought they acted like there are tons of adjustments they could make, but now they say that the tune is all they can do.

Joe275

i put a D&D on my '02 S4 and have the same "flat spot" between 2 and 4 grand. its not a problem anymore now that i know its there and anticipate it, but the first few low speed turns were interesting when it boged then shot out of the turn all on its own, Will, know of any places in our area to put it on a dyno and get a custom tune? now that i have the aftermarket can the RPM's climb alot faster now that she can exhale easier, and can't wait to throw on a K&N!

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"when i let off the throttle it gets all squirrely, so, i just stay on the throttle.."

FYI - I took my bike back for state inspection yesterday, I also had them check the tune. ITS RUNNING GREAT NOW! I think they used one of the latest tunes out. Not 100% sure.

I hate to say it but my 2003 UK spec S4 has not go t a 3k flat spot!

I have just come in from a brilliant 170 miles of country "A" roads & market-towns in typical British Summer conditions. [That is sunny weather with occasional showers & wet roads]

I made a particular point of checking the steps in the power curve. What I am now sure of is that mine pulls steadily from 2500rpm in top gear up a steady slope (about 1 in 15). There is actually a useful increase in torque between 3&4,000 rpm & then at 6,000 it starts to get serious.

After that it sounds the same as everyone else's. That is it starts sounding good at 8,000 is really flying at 10,000 and holds onto the power until 12-13,000.

But no flat spot. Is this just UK tune?

Looking at the power curves I wonder if the S4 cams cured the TT600 flat spot but Triumph did something else to the gas flow & timing to keep the power rising above 10-12k where the S4 goes to sleep. If that was so it would mean that tt600's could be brought to daytona tune quite simply?

Anyone got any opinions about this?

Jon

Will

First of all, there really isn't a TT600 flat spot if you have the bike set up right and with the right tune codes. If you are having problems with a stock bike, make sure that the dealer has the latest codes in your bike. If it is an S4, it should be whatever Triumph recommends. If it is a TT600, it should be 10115. Don't let the dealer freak out when you tell them to put that code in a pre-2002 bike. I am not sure if this advice works for a California model that hasn't had all the other bits taken off, though.

Joe- As far as places to get a custom tune done, there are any number of places that can do it. I have not had my bike on a dyno yet, but when it is time, I will either go to Cycle Barn, in Lynnwood or George Dean's shop in Mukilteo. Cycle Mart may have a dyno down in Lacey. If they don't, I am pretty sure that Renton Motorcycles has one. It doesn't matter that much whose dyno you use as long as you can chart the changes and what they do, as well as put a fan on your radiator so you don't get so hot that the bike dosen't run worth beans. If you have the latest TuneEdit, it has a Power Commander emulation mode that allows it to "talk" to a properly equipped dyno.

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sangsters

Will,

The jerking that this thread started with... I have that, in spades, in the 2000 - 3000 rpm range... It is honestly like riding a bucking horse.

Unfortuantely I am in that range a lot on my commute. Would you know if the current/new tune for the S4 attempts to deal with this? Also, would you know what the most current S4 tune number is?

Thanks.

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Will

I really don't know what the latest S4 tune number is. Bucking like that almost sounds like an IAC Valve problem. Early TT600s had some leaky IAC valves, and that makes it almost unrideable at low revs. If the throttle bodies are not synched properly, that can cause similar problems. The last thing to look at would be the CO setting. If the bike is set up too lean, it can be a real pain at low revs. It should be gutless down low, since it is a 600cc multi, but it shouldn't buck and kick.

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