Servo removal???

I'm going to be doing a lot of mods at once and wanted to know what benefit the servo removal will give me. I bought the bike with the powercore slip on. I'm doing the FMF programmer, AIS mod, and airbox mod (including flapper), and wanted to know whether or not I should go ahead and do the servo along with all that. Problem is I'm not exactly sure what the servo does and what the benefit to removing it is. I have seen write ups on how to do it, but not exactly sure the reasoning so if someone could explain I would greatly appreciate it.

Use the search feature please.

There's even stickies on this.

search:

servo

exup

AIS

flapper

exhaust



You'll get an error code if you remove servo and do nothing else.

Servo works EXUP in stock exhaust.

Use the serch feature. Lot's to read.

I did read the sticky but it was unclear to me what the benefit would be, anyway what is the exup?

The EXUP is an acronym that Yamaha Motor Co. in Japan says stands for EXhaust Ultimate Powervalve.
It's a butterfly-type valve in the exhaust pipe just before the muffler canister.
It opens and closes according to when the bike's electronics says it should.
The supposed benefit is good low-end power while having good top-end power, too, not trading one to get the other.

The servo motor is an electric motor under the battery that does the opening and closing of the EXUP.
There's a pulley on the servo motor that operates control cables which run to a pulley on the EXUP.

If you remove the stock muffler, the EXUP goes with it since it's welded to the pipe connecting to the muffler can.
Since you're disconnecting the control cables which run from the servo motor to the EXUP in order to remove the muffler, you can also remove the servo motor, too, since it will no longer be needed for anything.
The catch is that unless you do what's called a "servo removal mod", "servo eliminator mod", "servo sub mod", or similarlly-called name which fools the bike into thinking the servo motor is still there, your instrumentation will have an orange Check Engine Light (CEL) light up and annoy you as it tells you the servo motor is now missing.

Read this to learn about the low-buck way of eliminating the servo without the CEL:

https://wr250rforum.forumotion.com/t627-cheapest-diy-servo-bypass?highlight=servo+eliminator

Those are the basics of what's up with the EXUP and servo motor.

Drewmugx5t wrote:

I bought the bike with the powercore slip on.

If this is the case, your servo is doing nothing but adding weight to your bike.
Removing it will only decrease weight.
Leaving it won't hurt anything.


If you want to remove it, go here: click me <--clicky

Thanks guys, My friend got a stock bike yesterday and I saw what you all were talking about. I guess I will just leave it on for now. You def. cleared up my questions.

prolly just gonna buy the servo removal module from dynojet but cant find one for 2012, is there anything different on the 2012 or have they just not updated there catalog to compensate for later years? it only accounts for 2008-2010? ThAnKs

onewheelskillz wrote:

prolly just gonna buy the servo removal module from dynojet but cant find one for 2012, is there anything different on the 2012 or have they just not updated there catalog to compensate for later years? it only accounts for 2008-2010? ThAnKs

Only difference is color choice from what I've heard.

Have you read the thread on using a 5 cent resister?
Way much cheaper than buying a "module".

[quote="motokid"]

onewheelskillz wrote:

prolly just gonna buy the servo removal module from dynojet but cant find one for 2012, is there anything different on the
Have you read the thread on using a 5 cent resister?
Way much cheaper than buying a "module".

+1. I used a 10k and my light went out and has stayed out since I plugged it in. I still have the stock exhaust but the previous owner removed the servo and was riding it with the CEL on.