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Throttle Body Sync....

31K views 39 replies 16 participants last post by  Bill & Ted 
#1 · (Edited)
So in an effort to contribute to you svrider.com members I decided to take some pics for a so-so write-up on how to do a throttle body sync (mostly because there isn't one with pics that I know of). As this seems to come up a lot...mostly poeple asking if they should do it and everyone yelling at them to do it. It was intimidating for a n00b like me but fear not, it ended up being easier than my valve clearance check ;D. You will have to forgive me for the picture quality and for the daylight. I was home sick from work today and when I finally got around to doing this it was just getting dark.

NOW before anyone flames me for not taking the airbox off to do this I'm sorry. I know Suzuki in it's infinite wisdom says to take the airbox off and put some pantyhose over the TB intake but guess what? I thought it would be more realistic for drivng conditions if the air box was on, with the filter and snorkel intact! Ok, read on!

It was a total sucess as far as I can tell. I used the manometer but it ended up costing about $4.

I did have some two stroke oil layin around so that was used as suggested in the manometer link above. In construction of the tool the hardest part was getting all of the air bubbles out of the line. I had the most sucess using a bike pump to spread the oil through the tube and then after hanging it the oil collected at the bottom nicely as pictured below. The hardest part of actually performing the sync was fitting my hands through the frame to take the valve nipples off each throttle body and then fit the tiny hose back over them. A pair of needle nose pliers and a flathead screwdrier came in handy here. Ask me anything. ;D

Here are some Pics:

As you can kinda tell it was raining, and it rained all day....so this is my manometer with the oil nice and air bubble free....when i connected it to the bike the left side lost a little pressure so when I finnaly sync'd the TBs one side is higher on purpose.



This is a pic of my operation, I had a headlight strapped to my head like a surgeon.



If you can make out a golden valve/nipple coved by a plastic tube that is where I had to fit my hand. It was almost as hard just to get the little rubber cap off. The manual I was working out of said to take off the air box...now I understand why they wanted me to, easier access.



This is where the TB adjust screw is on my SV650K5, make sure your idle is set at 1300RPMs when performing this per the manual.




All Balanced! (Please note above where I mention that the fluid was off in this same way when I connected it so I was sure to balance it in the same way!)

 
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#2 ·
Just an FYI.

I did this (Syncing with air box on) a while back in a thread I believe was titled "dynamic throttle body sync". I even ran the bike down the road with vacuum gauges on it and learned that the difference between the cylinders at idle with the air box on and while running down the road with the air box on is essentially the same.

I rode the bike like this for a couple thousand miles. My average gas mileage during this interval was never higher than 49mpg. I just recently did another TB sync with the air box off, as the manual recommends, and haven't gotten below 50mpg in the last 6 tanks.

So, in short, watch your gas mileage. You may find that you made the problem worse by leaving the air box on. There is definitely a difference with the air box on versus off. Perhaps it is one that suzuki engineers accounted for.
 
#12 ·
I have the same issue with the fast idle. I checked the TP output voltage and it shows 1.21V as per the manual. Is there any other adjustment done for the fast idle?

The TB sync did throw off my fast idle so be aware that you may have to adjust your fast idle to the proper voltage.

I will let you know how my gas mileage fairs after my next couple tanks...problem is I'm quickly running out of season.
 
#8 ·
I had the dealer do mine since '07+ have to have an SDS hooked up. It was billed as one hour, so $75.
 
#10 ·
I were noticing that my engine didnt feel just right with the RPM very low and vibration at idle. I had 22,000miles on the bike. So i ran carbon cleaner that we use on cars. First thing i noticed is that the RPM started to go up. From about 1000 it started to climb to 3,000rpm. Rear cly had alot more deposits. Had to adj the rpm back down. Engine ran so much stronger right after that with idle very smooth. Up untill then i had to adj the idle up every few thousand miles and now i had to turn all the way back down again. Before the service when the engine was cold i didnt have fast idle after the cleaning it was back as new with about 500rpm higher when cold. Lesson is that its not always need adj but just service and cleaning.
 
#14 ·
I just did the TBS today. I heard that it was easy, but didn't realize how easy until today. I used the Carbtune Pro. I didn't really have any problems getting to the vacuum ports. I just held the tip of the tube with needle nose pliers to get the tube on, then I repositioned the pliers further back to get the tube all the way on the port. I found that it was much easier to get the tube on TB #2 than TB # 1.
 
#18 ·
I used the X-66P from GM. You can also use the BG product called 44K. But the GM is better. I have a pressurised canister that has a fine spray nozzle. I just took the air filter off and sprayed it into the throtall body while the engine is running. I switched between the front and rear cly untill the smoke stoped and the engine ran much better. Doing it this way it cleans all the passages and the intake. I did have to stop twice so i could lower the RPM as it keeped going up. You can also just pour it into the intake. Its not as good but still works. Just make sure you dont rev up the engine too high and dont pour too much or you would lock up the engine.. I also ran some water mist in between .. Then took the bike for a short ride after that an oil change. Dont forget the oil change to finish the job...

Alex
 
#19 · (Edited)
Hi there, plz SAVE ME

I spent the whole afternoon trying to sync this but is a living hell now.
*i have a problem finding the right nipple for the rear (found out AFTER removed it) cuz this have 2 nipples that it "seems" to be the same but in 2 locations. Maybe access, dunno.

*These pair of nipples were made by satan, specifically designed to get the worst out of me "dark-h8r"......was a cursing parade the whole time. But in the end it was pointless cuz they were gummy and melted so i had to cut em but once i had the TB in my hands......jezzz

*So there i was connecting the manometer hoses to it, started the bike and the front hose started to sucking and sucking so i turned it off. My guess is that both hoses must be connected at the same time or the vacum created will suck the oil inside towards the connected tb

Heres where i am now, concerned, frustrated and cursing that motherf"·$"!$ services manual and its black and white pics....

So could you plz enlight my way?

im thinking in doing a full service to TB according to manual but it say i need 2 different lubricants. Suzuki super grease (bought 1 once but i cant find it anymore) and other that i cant remember now. you tell me what can i get easy at a hardware store
 
#20 ·
I don't know that I would have bothered tearing them out, but I've never had to do it either, so I'm not much help. I don't know if I understand you correctly, but if the manometer is sucking fluid up through one side rapidly, then you're probably not getting a good seal on both TB's. One is leaking, so the other just vacs your fluid up. If it's slowly moving toward one side, then that side is just running higher than the other and you increase the vac on the low side until it sits still.

As for grease, I've always used regular old red wheel bearing grease. Works fine for me.
 
#21 ·
Being that the TBs are off the bike, you can do a mechanical sync. Set, say, a 1/16" drill bit between each throttle valve and body, adjust until they both fall at the same time when opening the linkage. It's not as accurate as setting dynamically but will be close enough.

Unless there is a specific problem that needs to be fixed, it's probably best to leave the TBs alone. Otoh, if you're like some folks here, including me, who like to muk with perfectly good working machines and sometimes screw things up (speaking for myself only :sbmfacepalm:), then go for it.

Grease for linkage and levers, molybdenum assembly lube is good; once it gets on stuff it doesn't like to come off.
 
#22 ·
I've taken to using my chain lube for things like linkages and such. The Dupont Chain Saver has teflon and it stays put where you put it. If in a pinch, you can do worse.

Oh...if you are using a home-made manometer, you MUST have both lines attached and the TB's semi-close to being balanced or it WILL suck your indicator fluid one way excessively. I wimped out and use a store-bought electrical gizmo to synch mine so I can't say I've experienced your problems. But, others sure have! Get them close like Tee says and you'll be able to finish the job to perfection once back on and running.

Those vacuum caps (at least on the 1K's) ARE a biotch to get to. Now that you have access, extend them out to where you can get to them easily and stick a screw or such in them to plug them until next time. If you flip the TB's over, you should see the holes that correspond to each nipple. As long as they are on the bottom (under) the throttle plate you can use it for synching.

Otoh, if you're like some folks here, including me, who like to muk with perfectly good working machines and sometimes screw things up (speaking for myself only ), then go for it.
I also plead guilty Your Honor!:)
 
#23 ·
I tend to be perfectionist and get annoyed by small things but this caps......they were the worst thing ive ever deal with!!!! its stupidly unreal the way they ****** me. Man, if i werent go for some beers with a buddy id still be mad.

So, resuming
both lines attached to what valves? i have 3 (2 looks the same to me) 1 for sure is for the front one, its clear as water, but the rear, dunno i have 2 of them.
And as for the "manometer" being plug at one side only, it didnt happen cuz it was a snug fit on every valve and i had to pull hard to get it off after turned the bike off.
Ill be looking for some spare caps tomorrow and see if i can get it running by nite cuz my vacations are over, summer is here until march and i want my bike growling on the road.

Thanks to you guys
 
#24 ·
Well i did it last nite properly.Same problem again but i didnt panic this time, just move the screw quickly and saw how they were way way off sync. STill the rear cyl was sucking the fluid but i made it in time and now she idles smooth (sounds different) and feels great. Í cant believe that i was running this bad and maybe my poor mileage was bc of this (35mpg)

But now im having this situation:
Did the tb service: cleaning, lubing, took inyectors for inspection, changed the orings, stv adjustment but im kinda worried bout the cError codes using dealer mode to set TPS and TBsync. I took the airbox off so i guess it could be normal cuz when i put it on and took a ride everything seemed fine but it annoys me the constan C13-C21-C49 codes.
In the past i dealt with the c49 and it was the pair valve disconnected. But this others dunno. (i know what they mean but i cant say if all of you see this while performing this adjustments cuz every pictorial i see is full of c00 like everythings normal)

And btw whats the order:
STV
TPS
TBS
??
 
#25 ·
Your bike is trying to tell you what is wrong with it! C13 is intake air pressure sensor (likely not plugged in properly) and C21 is intake air temp sensor (again likely not plugged in properly).

http://www.svrider.com/forum/showthread.php?t=110382&highlight=c21+code has a code chart. Very handy! Double check your connections/hoses and you will likely find your trouble.

The order I adjust things is synch TB's, set idle speed, set TPS, set STV's then their sensor. If anything moves (like idle speed) when you change something make sure to correct it and double check that you didn't muck up the synch.
 
#27 ·
Doesn't look like your fast idle is working properly. Did you adjust the STV position sensor per the manual? If you look at the linkages, you can see how the STV's will open the main throttle a bit when cold. Adjust to open them up a bit more to speed up the cold idle.

I'm going off of how the 1K works....which I believe is similar to the 650. If it is different (I've only got the 1K manual) then sorry! But it should idle faster when first started and then slow down. The colder it is...the higher it should initially idle. You need to adjust it up a bit it seems.
 
#29 ·
The STV motor positions the valves according to what the sensor tells the ECU. When cold, it will move the motor until the sensor reads X.XX volts. If you adjust the sensor up or down, the ECU will still move the plates until it see's the same voltage, you just then get the plates open farther or less. If you go too far, the plates can bind and not reach the proper voltage and I think it will set a Trouble Code. But...it isn't likely if yours is anything like mine that you will have enough adjustment room to get in bad trouble. But...be safe and keep the sensor within the stock parameters and the bike will run the way it should.

I tried to get my STV's as far open as I could and still have the sensor adjusted properly according to the manual. It runs out of adjustment if you go crazy, but you should be able to open them significantly and still keep the sensor in the proper range. I think this will help it although mine ended up ventilated by a 3/8" drill to get it to run the way I thought it should. These engines are great as they respond well to small adjustments and you can tune them to your desires.
 
#30 ·
I did my TB sync yesterday using a homemade manometer like the OP made. I had an absolute horrendous time with this apart from those blasted vacuum part caps (which I replaced all 3).

Anyway my problem would be that I would get the TBs synced (or so it appeared), but if I let it sit running after I got it adjusted properly for a minute or two they would all of a sudden be off again!!! :dizzy: WTF is going on.

It was really frustrating so any info would be helpful. I ended up just getting it adjusted even then turning it off right away so I wouldn't know if it eventually was off again.
 
#31 ·
Just make sure theyre not waaaay out of sync. Using a home manometer isnt as accurate as a pro tool is. Mine was way off but at least theyre more in sync now. You can hear how your bike sounds different and take it for a spin and see how it feels.

My problem was the rear cyl sucking all the fluid so i quickly turned the screw until it stopped and "synched"
 
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