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I wanted to do the TPS adjustment on my bike for the last few months and just never got around to it until last night. I was a little intimidated by the procedure on-line given peoples problems with the "french cheese" torx bolts and the touchy adjustment but my experience was nothing but smooth.

I followed the instructions shown here:
http://forums.sv650.org/viewtopic.php?t=10245).%5B/img%5D

After checking the idle I inserted the "dealer mode tool" and checked the factory setting which was as expected set to 3000 rpm. At this point I was a little scared about stripping out the torx bolts but I had no problems loosening them (I had a good quality socket). After I had the bolts loose I made one initial adjustment on the TPS (not more than 1mm CC) and checked the setting on the display. Wouldn't you know that it was now perfectly set at ~1450rpm. I was so stoked! For once I wasn't stuck in the garage late into the night trying to get the adjustment just right. I shut down the engine, bolted everything back together and took her on a little test ride and what a difference the adjustment made.  The bike is not at all jerky at low speed/low throttle and is now much more responsive off idle.

I definitely recommend the adjustment to anyone with an 03+ SV. The procedure is really quite simple and the result is awesome!!
 

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same instructions I used.

I had to do a little more fiddling with it than you did. Here's what I came up with to get it perfect. Get the TPS in just the right place that the line on the display moves at IDLE SPEED. Then, tighten your screws down. Tightening the screws moves the TPS a little bit, and put mine in nearly perfect position (about 1600 rpm).

Note that you dont have to have it at exactly 1450 rpms...you probably do not want it any lower than that, a wee bit higher is ok and still MUCH better than the factory setting. I would think anything below 1800 or so would be a-ok.

I used the correct sized torx security bit and I didnt find the screws to be very soft.

I did have a little trouble getting to the bottom screw...my solution was to put the torx bit into a socket (1/4") and use a socket wrench. Just be carefull you dont turn the wrench upside down, as the bit will fall out, you wont be able to find it, you'll curse a while, and have to go buy another one (that's what happened to me, anyway).
 

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Without a doubt the best cheap mod you can do. I didn't have a lot of daylight when i did mine so it's set at 1800rpm but it's a far cry better than the 3000rpm set by the factory.

+1
 

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So, why is factory set at 3K RPM?
Does it make the engine run cooler?

(I did mine a few months back as well, spent quite some time adjusting it).
 

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heres my question starting at #10 procedure on that link. its says turn the key ON then the next step has you moving the throttle (tack is moving). then #12 says turn off the engine. SOOOOOOOOOOOO what shoud i do run the bike at step 10. or is step 12 just mean "turn off the key"
 

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gotalf said:
heres my question starting at #10 procedure on that link. its says turn the key ON then the next step has you moving the throttle (tack is moving). then #12 says turn off the engine. SOOOOOOOOOOOO what shoud i do run the bike at step 10. or is step 12 just mean "turn off the key"
So at step 10 you turn on the ignition first and make sure you have the line and couple of zeros displayed and then start the bike to check the setting(the bike needs to be running to check the setting....so at step 12 you should be turning off the engine.
 

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Amazing...I did this adjusment yesterday and it really makes moving in the low gears a whole new experience...My TPS was set at 3,800 rpm!
 
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Mine was set at 2500 - not too bad I suppose. But damn those funky security Torx screws!!!!!

It was too late at night to go out and try to find the right tool. But when you can't wait...Fabricate!

I vice gripped off the top one, hacksawed a slot in the bottom one and turned it out with a screwdriver. I replaced them with socket hex cap screws. Voila! Easy to adjust anytime.
 

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toddpnewton said:
I replaced them with socket hex cap screws. Voila! Easy to adjust anytime.
Great idea..I thought of that too while i was scraping my knuckles tightening them back up...do you remember what size you used?
 

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So I just got my bike this past sat... what is a TPS adjustment mod?



edit: nevermind, just clicked on the link and read what the poster had to say... great read as I was wondering if there was something I could do to eliminate that bike jump.
 
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JPDD said:
Great idea..I thought of that too while i was scraping my knuckles tightening them back up...do you remember what size you used?
Sorry, I don't. M6? The ones I had were a bit long, so I don't know the correct length eithder (I had to shorten them). I have a huge stash of extra metrics laying around from many previous bikes. Saves me a trip to the store almost every time :).
 

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Does anyone know what changing this does over all? If it is so important to smooth operation why would it be set so high coming from the factory? Also, does this change noticeably impact fuel consumption?

Those are the questions that have kept me from doing this...so if anyone actually knows the answer(s) I'd love to hear them.

TIA
 

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The TPS (throttle position sensor) senses the position of the throttle (duh), and at a certain throttle position, tells the fuel injection computer to inject more fuel. Setting it to a lower position really helps make the bike a lot smoother and easier to ride in lower rpms. I have no problem riding at 2000 rpm in most gears, where before I couldn't let it drop below 3200 or so without getting really jerky and hesitant.

Why is it set that way from the factory? emissions is my guess. who knows?

does it impact fuel consumption? not at all that I've noticed. just checked mine last fillup, was 50.9 mpg. As I understand it, it wont affect how much fuel is injected per se, it just affects what throttle position the injectors start injecting more.

easy, cheap, and will make every single ride more pleasureable. what are ya waiting for?
 

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I just did mine and it worked fine. If you are thinking of doing this, I'd recommend it, given what I currently know. I would also add a couple suggestions.

a--Plug you are looking for LOOKS black, due to large rubber cover over it. It lives under or outboard of subframe, at least on my bike, and has just enough wire to make it sort of accessible. Top of rubber cover says up and you can see the 6 wires connected to the back.

b--When you are moving TPS around, try leaving Torx bolts snug and rotate unit around bottom bolt by inserting small screwdriver into oval gap on either side of top bolt. Use the "old car points adjustment" method of tweaking screwdriver back and forth to make incremental adjustment.

c--Replace Torx bolts with other metric hardware. I didn't this time, but will next time. If I ever have to dick around with it out on the road, it will be far easier to deal with a hex head bolt.

Those things said, I plan on looking into two things.

1) What rpm does Suzuki suggest setting it at? Factory manual I have mentions very little about it. "If TPS needs adjustment, do this...", but it doesn't give a number.

2) When we make this change, does it slide entire FI map down (say from 3000 to 1450rpm) and alter the relative position of the entire fuel map OR does it simply lower the point that the minimum amount of fuel is added? Also not mentioned in manual.

I've adjusted on the faith that everyone else's bike hasn't blown yet, but my curious mind would love to know some facts about how it operates, rather than just what works.

Rides like a bike now, not a light switch. That's good.
 

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I just printed all the info out! Wish me luck Chief! I am going in!!!!!! (This weekend!) I will post here when done.
 

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I did it last night and it took about 15 minutes. Throttle control is much smoother. I have a lot more confidence giving her a little gas mid-corner. :)
 

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2wheelsrbest said:
2)  When we make this change, does it slide entire FI map down (say from 3000 to 1450rpm) and alter the relative position of the entire fuel map OR does it simply lower the point that the minimum amount of fuel is added?  Also not mentioned in manual.

I've adjusted on the faith that everyone else's bike hasn't blown yet, but my curious mind would love to know some facts about how it operates, rather than just what works.

Rides like a bike now, not a light switch.  That's good.
This is from the Haynes Basic Techbook:

The TPS is used to provide information regarding engine load (amount of throttle opening) and rate of change of load (how quickly the throttle is being opened or closed). ...On machines with fuel injection, it is fitted to the throttle bodies and the information it provides is used to determine fuelling requirements, giving it a dual role.

The sensor is a small unit which acts as a variable resistor and is keyed to one end of the throttle shaft. As the throttle is turned from fully closed to fully open, the resistance of the sensor changes, which means that a voltage supplied across it will also change. The ignition control unit or engine management system constantly reads changes and rates of change in either the resistance or the voltage, and compares each reading to those before it to determine exactly how the throttle is being used, enabling it to use the information to determine engine load (along with other factors). This information is compared with the information stored in the ROM and matached to pre-programmed timing advance settings. On fuel injected motorcycles, the information is also used to vary the amount of fuel being injected.
 

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Excellent info. Another reason I am let down by the factory manual...

One more thing I thought of to add to the Make It Easy list is the "dealer tool" I made. I had no luck with multi-strand wire as suggested, so I found a small paperclip. I cut one 180degree bend section off clip and trimmed so that it had equal length legs. I then wrapped tape around the bend and bulk of the legs, leaving only two small leads sticking out. This was very easy to push into the connector and would not short out like plain old paperclip could.
 
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