surfinpig
Member
The stumble was driving me nuts. On a trip this year I had a dealer do a tbs which helped. Recently it got worse. I just turned out the 2 screws and all is fine on my short test ride. Great write up!
Airscrew Adjustment to fix off-idle stumble and Throttle Body Sync - w/ pigtails
- Thread starter SpeedStar
- Start date
Dogdaze
Well-Known Member
Did you use a harmonizer or tubes of any kind?surfinpig said:
Or did you just turn out the screws a little?
surfinpig said:
If you work where I think you do, my office is on the Metro also and I could loan you a sync tool.
Sorry not a very good poster but love my S10 and have learnt a lot from this website so thought I'd best post on an issue I had which has been resolved and may help a fellow rider. Got my bike (2011) back from a service (non Yamaha dealer) and my bike had started to stumble between 1000 and 3000 rpm and stall on tick over once warm. Pulling away was a nightmare and felt like it was missing or starved of fuel but was running fine over 3000 rpm. Tried the adjustments and was still having problems. Took the bike back to Yamaha dealer for its next service and spoke to them about the problem and the only fault they could find was damage caused by a badly fitted spark plug resulting in me being down one plug. Guessing it runs on all four on start up and over 3000 rpm and two plugs once warm and up to 3000 rpm but might be completely wrong! A little bit of repair work conducted and the bike has been returned running absolutely fine again. I'll be sticking with the approved dealer in future.
surfinpig
Member
Thank you for the offer. I live up in Philadelphia though. And I do need to sync them now. After a long ride the stumble is still there. But by backing them out I feel like she has more mid range power.Checkswrecks said:
surfinpig
Member
Has anyone synced at high rpm? Seems to still have the Stumble a day after syncing. This is driving me nuts
Hello,
after the Airscrew Adjustment i want to adjust the CO for every Cylinder. I read about a possibility to use a Exhaust Analyzer to adjust each Cylinder with the right CO Values.
I put some measuring connections at my Downpipes and there should be a Instruction to measure the CO Value for every single Cylinder.
Does anyone done this before and how does it works?
At some Dealers they offer this adjustment with a Original Yamaha Downpipe (wich have to be ordered first) for the measurement. I takes about 2-3 Hours and around 200 Euro.
Thank you for any Information.
Ralf
after the Airscrew Adjustment i want to adjust the CO for every Cylinder. I read about a possibility to use a Exhaust Analyzer to adjust each Cylinder with the right CO Values.
I put some measuring connections at my Downpipes and there should be a Instruction to measure the CO Value for every single Cylinder.
Does anyone done this before and how does it works?
At some Dealers they offer this adjustment with a Original Yamaha Downpipe (wich have to be ordered first) for the measurement. I takes about 2-3 Hours and around 200 Euro.
Thank you for any Information.
Ralf
rid34fun
Member
After reading through this entire thread (ok I have nothing else to do 
), I wanted to try this on the 2014 just to be sure this mod is useful for me and my 2014. I appreciate all the attempts and comments, they have been very useful. I have a 2014 S10 and I have done 3 tests with this mod. Here are my results, obviously no measurements can prove or disprove, but here is what I found. I have gauges that I have used to balance many a carb/TB, so that made it easy. I love that Yamaha lets you tilt the tank so easily. I used a girls basketball to hold up the tank My base airscrew, colored white is on the left side of the bike, not the right. All tests done in T mode, and then S mode checked to verify nothing changed there.
1. Made sure my TB's were balanced at the factory setting. Rode for a couple of weeks to get a butt baseline. The 2014 seems to fuel better, as mine exhibits none of the stumbles read about here, but was a little soft off idle (yest T mode is softer, but still a little stumble exists), so still not perfect either, so some changes were worth a try.
2. (3/4) First I turned the white screw out 3/4 turn and balanced the TB's using the right air screw. I have to turn the right out several turns past 3/4 to get them to balance. The bike ran great after doing this, however, when the mornings got into the 40's, the S10 on the cold circuit after starting would miss quite a bit until it warmed up. That was a small concern as I ride all year if possible. That concerned me enough to try other variations on this mod. I rode a few hundred miles with it this way. Each time I started the bike, it had some mis fires when the outside temp was cold. Once warm, the bike runs good.
3. (1/2) Next option turn the white screw out 1/2 turn, and balance using the right screw. Bike ran well, felt like the same as the 3/4' out when warm, and had less misfires when cold starting, but still had a few. Rode this way for a 100 miles over a week or so. Ran good.
4. (1/4) Last option for me was to turn the white screw out 1/4 turn, and balance using the right air screw. The bike seems to run just as smoothly as the 3/4 out, but has no misfires when cold starting. This seems like the best option of the 3 options above. No misfires when cold, and off idle is smooth. I plan to keep this option, as it seems to be the smoothest for my S10.
Thats my summary, I hope this helps!
), I wanted to try this on the 2014 just to be sure this mod is useful for me and my 2014. I appreciate all the attempts and comments, they have been very useful. I have a 2014 S10 and I have done 3 tests with this mod. Here are my results, obviously no measurements can prove or disprove, but here is what I found. I have gauges that I have used to balance many a carb/TB, so that made it easy. I love that Yamaha lets you tilt the tank so easily. I used a girls basketball to hold up the tank My base airscrew, colored white is on the left side of the bike, not the right. All tests done in T mode, and then S mode checked to verify nothing changed there.1. Made sure my TB's were balanced at the factory setting. Rode for a couple of weeks to get a butt baseline. The 2014 seems to fuel better, as mine exhibits none of the stumbles read about here, but was a little soft off idle (yest T mode is softer, but still a little stumble exists), so still not perfect either, so some changes were worth a try.
2. (3/4) First I turned the white screw out 3/4 turn and balanced the TB's using the right air screw. I have to turn the right out several turns past 3/4 to get them to balance. The bike ran great after doing this, however, when the mornings got into the 40's, the S10 on the cold circuit after starting would miss quite a bit until it warmed up. That was a small concern as I ride all year if possible. That concerned me enough to try other variations on this mod. I rode a few hundred miles with it this way. Each time I started the bike, it had some mis fires when the outside temp was cold. Once warm, the bike runs good.
3. (1/2) Next option turn the white screw out 1/2 turn, and balance using the right screw. Bike ran well, felt like the same as the 3/4' out when warm, and had less misfires when cold starting, but still had a few. Rode this way for a 100 miles over a week or so. Ran good.
4. (1/4) Last option for me was to turn the white screw out 1/4 turn, and balance using the right air screw. The bike seems to run just as smoothly as the 3/4 out, but has no misfires when cold starting. This seems like the best option of the 3 options above. No misfires when cold, and off idle is smooth. I plan to keep this option, as it seems to be the smoothest for my S10.
Thats my summary, I hope this helps!
Tempesc
Member
It does - really helpful, thank you!
Sent from my iPhone using Tapatalk
Sent from my iPhone using Tapatalk
RCinNC
Well-Known Member
I've done two throttle body synchs using the information in this thread, and both worked out great. Each time I did one, I had been experiencing a weird vibration in the engine; very subtle, and maybe it wouldn't have even been noticed by someone who wasn't familiar with the bike. Both times, the synch cleared up that vibration (the best way to describe it would be that the engine seemed to "growl").
One odd thing though; after doing my second synch, I found that I had no more room on the non-standard side to adjust (my standard side is actually on the left cylinder). It was screwed all the way in. I knew this would present problems in the future. I decided to follow the instructions for the air screw adjustment to fix the off idle stumble, though my bike hadn't suffered from that problem. I backed out the standard airscrew by 270 degrees, then synchronized the throttle bodies. I was able to get a better balance between the throttle bodies after that adjustment, and everything seems to be running good now.
Has anyone else ever had that issue, where they ran out of adjustment room on the non-standard screw?
One odd thing though; after doing my second synch, I found that I had no more room on the non-standard side to adjust (my standard side is actually on the left cylinder). It was screwed all the way in. I knew this would present problems in the future. I decided to follow the instructions for the air screw adjustment to fix the off idle stumble, though my bike hadn't suffered from that problem. I backed out the standard airscrew by 270 degrees, then synchronized the throttle bodies. I was able to get a better balance between the throttle bodies after that adjustment, and everything seems to be running good now.
Has anyone else ever had that issue, where they ran out of adjustment room on the non-standard screw?
Tombraider2
2014 Team Blue
What are you all using for a sync tool ?
Anwar Namtut
Member
I have this question, too. Can this be use? http://smile.amazon.com/gp/product/B00N3PPZZY?psc=1&redirect=true&ref_=ox_sc_act_title_1&smid=AGBVZLGDTMGHOTombraider2 said:
I finally got a Harmonizer after years of waiting. Highly recommended.
http://advrider.com/index.php?threads/harmonizer-vacuum-multi-tool-it-aint-your-daddys-twinmax.701625/
http://advrider.com/index.php?threads/harmonizer-vacuum-multi-tool-it-aint-your-daddys-twinmax.701625/
serhan
Member
Thanks very much, totally transformed the bike!
S.
S.
::026::regulator said:
Did the TB synch, and clutch basket, bike is so much smoother now (2012).
RhodeTrip
Member
I wonder if Is there the same type of improvement expected from a 2015?serhan said:
Jim
A TB sync on my '15ES made a notable difference although not a profound one. Right side screw was all but closed, only cracked open about 20 degrees. Now it's set open about 270º as recommended by some and the left side adjusted to balance it out on the Harmonizer. Pretty dang smooth in S mode with TC off, heh heh...
serhan
Member
I use a morgan carbtune pro, only use the two bars out of the four.
taskmaster86
Active Member
I just ordered the Harmonizer as they are back in stock.
Hopefully I can get my TB synched next week. I have 1,500 miles on my S-10 and I get a bit of surging at around 2,000 RPM. The snatchy/surgie throttle feeling makes low speed maneuvers difficult.
Also, after reading all of this, I am surprised how many people lift the gas tank to do this job. Sure it might be a little cramped but it doesn't look the tank NEEDS to be lifted? The Yamaha service manual doesn't say anything about lifting the gas tank when you do this job. I think I could get a very long skinny screwdriver in the left side to make the adjustments. The right side looks like it has plenty of room to work.
I will post here again once I am done.
Hopefully I can get my TB synched next week. I have 1,500 miles on my S-10 and I get a bit of surging at around 2,000 RPM. The snatchy/surgie throttle feeling makes low speed maneuvers difficult.
Also, after reading all of this, I am surprised how many people lift the gas tank to do this job. Sure it might be a little cramped but it doesn't look the tank NEEDS to be lifted? The Yamaha service manual doesn't say anything about lifting the gas tank when you do this job. I think I could get a very long skinny screwdriver in the left side to make the adjustments. The right side looks like it has plenty of room to work.
I will post here again once I am done.
taskmaster86
Active Member
We had some nice weather so I balanced my throttle bodies today!
I did decide to lift the gas tank to do it although I am sure you could do without lifting the tank.
My right side TB screw had white paint on it and it was tightened all the way in. I unscrewed it 3/4 of turn and then used the other screw to balance it out. The Harmonizer really made this easy. I got the system to balance so well that it was steady on 0 (perfectly balanced) when I was done. I used 1/8" vacuum hose for the left side connections. I was able to connect the hose that comes on the harmonizer directly to the barb on the right side vacuum port. I did use small spring clamps on every connection and had no check engine lights or other problems.
Once I got everything put back together, I was amazed at the difference. The idle was more steady, the engine sounds a lot different and the engine is a lot smoother as well. I am really surprised how much of a difference this makes.
I did also replace the left side gas tank hold down bolt with a regular hex bolt. Using a hex bolt allows you to use a ratcheting wrench to undo the bolt. A ratcheting wrench is much easier to use in the tight space compared to get an allen key that you would normally have to use. The Bolt size is M6x1x30 if you are going to do this.
If anyone lives in the south eastern, CT area and needs help with this, let me know! Thanks again for everyone's help in this thread!
I did decide to lift the gas tank to do it although I am sure you could do without lifting the tank.
My right side TB screw had white paint on it and it was tightened all the way in. I unscrewed it 3/4 of turn and then used the other screw to balance it out. The Harmonizer really made this easy. I got the system to balance so well that it was steady on 0 (perfectly balanced) when I was done. I used 1/8" vacuum hose for the left side connections. I was able to connect the hose that comes on the harmonizer directly to the barb on the right side vacuum port. I did use small spring clamps on every connection and had no check engine lights or other problems.
Once I got everything put back together, I was amazed at the difference. The idle was more steady, the engine sounds a lot different and the engine is a lot smoother as well. I am really surprised how much of a difference this makes.
I did also replace the left side gas tank hold down bolt with a regular hex bolt. Using a hex bolt allows you to use a ratcheting wrench to undo the bolt. A ratcheting wrench is much easier to use in the tight space compared to get an allen key that you would normally have to use. The Bolt size is M6x1x30 if you are going to do this.
If anyone lives in the south eastern, CT area and needs help with this, let me know! Thanks again for everyone's help in this thread!