2014 Stumble on accel.

[Fred W]

Please provide more details if possible. I find this very interesting because, as has been discussed elsewhere, there seems to be variations in the amount of vibration at higher rpm that could be attributable to throttle plate misalignment. How did you (or someone else) determine that the butterflies were out of sync?

Thanks.

 

[RaYzerman19]

The owner reported high idle of 2000 rpm, would not drop below that. Sync attempted, then airbox removed to confirm one butterfly (#4) not closing. No measurements to say how much but obviously big enough to cause a significant issue. It was then buttoned back up and will be making a trip to the dealer for warranty.

 

[Fred W]

Wow, I'm not even sure how that could happen on a 3rd Gen. All 4 butterflies are screwed onto the same shaft that has flats machined into it to locate the butterfly angles. Keep us posted on what they find. Maybe a bent or loose butterfly?

 

[K_Flyer]

Wow, I'm not even sure how that could happen on a 3rd Gen. All 4 butterflies are screwed onto the same shaft that has flats machined into it to locate the butterfly angles. Keep us posted on what they find. Maybe a bent or loose butterfly?

Tolerancing becomes an issue, as soon as you bolt parts together. You need some clearance around screws to get them in the hole in the plate and still line up with the threaded hole in the shaft. Similarly, the throttle bodies are bolted down (I think!) so I can see many ways for small miss-alignments to occur. A though or two off and you will see a problem. Rather like the navigation on your GPS, the surprising thing is that it works as well as it does.

I well recall the experience 50 years ago trying to sync the three carbs on a Healey 3000!

 

[its just rain]

Thought I would post an update on my poorly running '14. I ordered a Throttle Position Assembly (sensor) and had my dealer install it. I have a new bike with 50,000 miles on it. Have to say it runs better than my '11 ever did.

 

[escapefjrtist]

Thought I would post an update on my poorly running '14. I ordered a Throttle Position Assembly (sensor) and had my dealer install it. I have a new bike with 50,000 miles on it. Have to say it runs better than my '11 ever did.

It was a long time coming, glad the '14 is finally repaired!

--G

 

[Bill Lumberg]

Glad you got it running. It was a long five months and an uphill battle getting Yamaha to fix mine (under warranty). You did well to buy the part and to have it installed. Congrats.

 

[dcarver]

good stuff.. congrats.