Syncronizing Throttle plates (butterflies)

Did a TB sync the other day. But first wanted to see how far off the throttle plates (butterflies) were. So I seated the air screws and then checked the TP's sync. with my CarbTune and they were off quite a bit. Cyl. 1 and 2 were very close to each other and cyl. 3 and 4 were also very close to each other. But the diff between 1-2 and 3-4 was quite a bit. Actually I was quite surprised how much they were off with the bike running as well as it is. But getting at the TP adjusters looks like a pain! Plus I don't have a good 8mm wrench so I just left them alone for now and did the TB sync. Helped a little but it seems to me a waste of time when the TP's are so far out of sync. I noticed there was paint on the TP adjustmet screws and locknuts so I went to the Stealer and asked him if adjusting them would void my warrant or something and he said no, so that's good news. Will pull the bike apart again as soon as I can get a Snap-On 8mm wrench to do the TP adjustment. Just will have to start early so I can figure out what is the best way to get at everything? Might have to take some stuff off or apart to get at the adjusters which might mean I can't run the engine until I make the adj. and put everything back together? Cyls. 1-2 are pulling more vacuum so I can just open those plates a little more or close 3-4 a little more to get the TP's closer. Hopefully I can get at the adjusters without taking off to much stuff so I can do the adj. with the engine running and the CarbTune hooked up?

Also replaced the plugs and the old ones looked GREAT for all the cyls.. Plus it's nice to now have an extra set of plugs to carry on the bike in case the EFI ECU screws up and fouls the plugs that are in there now. But as expected the engine is running to lean for my taste.

I tried the BJM. Tried +4 and then +2 but didn't like the way my bike was running so I undid the BJM and we're back to normal. Oh yeah, the stock setting for my '08 were 10-10-10-10.

Personally, I'd just leave well enough alone.

You don't have a vibration issue. Your plugs are fine. If it ain't broke, why fix it? The road to hell is paved with good intentions.

It can really go downhill from here.

bramfrank said:

Personally, I'd just leave well enough alone.
You don't have a vibration issue. Your plugs are fine. If it ain't broke, why fix it? The road to hell is paved with good intentions.

It can really go downhill from here.

Click to expand...

Well enough isn't good enough for me! I know this bike can run better and smoother than it does. Very disappointing that Yamaha can't even put their engines together correctly with Throttle plates that are at least close.

Alakso said:

bramfrank said:

Personally, I'd just leave well enough alone.
You don't have a vibration issue. Your plugs are fine. If it ain't broke, why fix it? The road to hell is paved with good intentions.

It can really go downhill from here.

Click to expand...

Well enough isn't good enough for me! I know this bike can run better and smoother than it does. Very disappointing that Yamaha can't even put their engines together correctly with Throttle plates that are at least close.

Click to expand...

Alasko your never suppose to adjust the throttle plates on a fuel injected bike. There are air screws on the throttle bodies and they are what you use to sync the throttle bodies. Do you have a factory repair manual it will explain the proper way to sync the throttle bodies.

Eric

VTFJR13 said:

Alakso said:

bramfrank said:

Personally, I'd just leave well enough alone.
You don't have a vibration issue. Your plugs are fine. If it ain't broke, why fix it? The road to hell is paved with good intentions.

It can really go downhill from here.

Click to expand...

Well enough isn't good enough for me! I know this bike can run better and smoother than it does. Very disappointing that Yamaha can't even put their engines together correctly with Throttle plates that are at least close.

Click to expand...

Alasko your never suppose to adjust the throttle plates on a fuel injected bike. There are air screws on the throttle bodies and they are what you use to sync the throttle bodies. Do you have a factory repair manual it will explain the proper way to sync the throttle bodies.

Eric

Click to expand...

Hi Eric, thanks for your concern. Here's a link to a discussion I was having about TB sync.

TB Sync Clicky

Stolen from a post by Radman in April of '07:

I've been doing synch's in a different fashion after having done a few hi-speed unauthorized synchs and a few regular (normal) synchs. I've found this method gives very accurate vac readings with little additional work.1) Set up gauge etc normally.

2) Adjust all the TB bleed screws to 1/2 turn open. This eliminates the bleed settings from the equation.

3) Check readings

4) Now, rather than adjust bleed screws, adjust the throttle plate screws to get even readings instead. At idle.

5) Crank rpm's to 4500 and observe readings, adjust plate screws as needed-shouldn't take but the smallest adjustment to get all in line.

6) Allow bike to idle, adjust idle speed, NOW adjust bleed screws for even readings. Once again, should be pretty damn close.

7) Buzz up to 4500 rpm's again. Bleed settings will alter speed settings very slightly, unless a bleed screw is cranked way out of whack compared to the others-3 turns out on #2 for instance. This indicates something is crossed up, reset all to 1/2 turn and start over.

8) Bleed screws should only need the slightest adjustment to even up the idle numbers. Actually, if all is happy in motorville, you may find they need no adjustment at all, other than turning all down 1/4 turn to get idle speed to about 1000-1100 rpm. Mine are all at about 1/2 turn, this seems to be best.

Keep in mind a synch is done to get 4 cylinders to operate as one-this is the key to smoothness and good power/mileage/rideability. Done right, with care and attention to detail, you won't believe how smooth you can get this motor to run. Another suggestion is to do the high speed adjust at the rpm you find yourself using most often, though the 4500 tends to be the peak vibe number for this motor

Click to expand...

Haven't tried it yet, so no idea what it will do for me....

Toecutter said:

Stolen from a post by Radman in April of '07:

I've been doing synch's in a different fashion after having done a few hi-speed unauthorized synchs and a few regular (normal) synchs. I've found this method gives very accurate vac readings with little additional work.1) Set up gauge etc normally.

2) Adjust all the TB bleed screws to 1/2 turn open. This eliminates the bleed settings from the equation.

3) Check readings

4) Now, rather than adjust bleed screws, adjust the throttle plate screws to get even readings instead. At idle.

5) Crank rpm's to 4500 and observe readings, adjust plate screws as needed-shouldn't take but the smallest adjustment to get all in line.

6) Allow bike to idle, adjust idle speed, NOW adjust bleed screws for even readings. Once again, should be pretty damn close.

7) Buzz up to 4500 rpm's again. Bleed settings will alter speed settings very slightly, unless a bleed screw is cranked way out of whack compared to the others-3 turns out on #2 for instance. This indicates something is crossed up, reset all to 1/2 turn and start over.

8) Bleed screws should only need the slightest adjustment to even up the idle numbers. Actually, if all is happy in motorville, you may find they need no adjustment at all, other than turning all down 1/4 turn to get idle speed to about 1000-1100 rpm. Mine are all at about 1/2 turn, this seems to be best.

Keep in mind a synch is done to get 4 cylinders to operate as one-this is the key to smoothness and good power/mileage/rideability. Done right, with care and attention to detail, you won't believe how smooth you can get this motor to run. Another suggestion is to do the high speed adjust at the rpm you find yourself using most often, though the 4500 tends to be the peak vibe number for this motor

Click to expand...

Haven't tried it yet, so no idea what it will do for me....

Click to expand...

That's exactly the way I do it and it works good. One thing to note though. Notice he said to set the idle speed if required and then do the idle bleeds. That is good info. I had the thing all synced perfect once and the last thing I did was set the idle speed. Well that method ruined all my settings. I don't know why but if you make a change to the idle speed it will botch up your sync. settings.

Well I guess you learn something new everyday. maybe I'll have to give this a try since I sync'd my bike the way the OEM repair manual said to do it

Eric