Throttle Body Sync - #4 loses vacuum at 4k rpm?

[Darksabre]

Hey guys,

So I built my own manometer (followed the guide on the FZ6 forum) to do my throttle body sync this weekend. I hooked it up, turned her on, and was able to get 1, 2, and 4 very close to 3 (the reference TB according to the FZ8 service manual). After that, I adjusted the idle rev to about 1200rpm, and did some minor adjustments to get them all sync'd up again.

All good so far...

I remember reading in more than one place that people have been revving their engines to 4k RPM to see what the sync looks like in that range. I decided to go ahead and do that, but something weird happens. As soon as I start raising the RPM's, the #4 oil level drops (loses vacuum). By the time I'm at 4k RPM, the #4 tube is completely empty! It does this every time.

What I dont get is how I could get it so perfect at idle, and then have it be that far off at 4k.

 

[TorontoAlex]

Try swapping out the tube with another tb to make sure it's not the manometer. You can check your seal between TB and intake with soapy water.

 

[Darksabre]

Try swapping out the tube with another tb to make sure it's not the manometer. You can check your seal between TB and intake with soapy water.

Nuts...that would have been a good idea... I'll try swapping the cables around next time. For now, the bike seems to be running just fine (at idle and at speed).

 

[OdinSon]

I had the same issue on my bike. Swapped tubes and checked fittings. In the service manual it made no mention of checking at 4k so ultimately I disregarded it. Bike is running perfect so no need for me to worry about it.

 

[myklobe]

How often should a throttle body sync be done (and what are symptoms that it does need to be done)? I have 750 miles on mine and just wanted to start good habits if this is something I should be doing regularly.

Thanks!

 

[9 Lives]

How often should a throttle body sync be done (and what are symptoms that it does need to be done)? I have 750 miles on mine and just wanted to start good habits if this is something I should be doing regularly.

Thanks!

According to the owners manual after the first 600 miles and then at 6000 mile intervals. Check and adjust if necessary. The TB sync only effects idle, if its not idling smooth a TB sync may help.

 

[myklobe]

Thanks, I saw that in the manual today... Guess I had no idea it was that picky and gets that out of sync so quickly with TBs.

Guess I'm building a manometer tonight since I just broke 700 miles