2012 wr450f throttle stop screw

[mccorb]

I've done a little searching but haven't found any answers to this question. I am getting ready to buy a 2012 wr450f. I have seen a lot of info on installing a new GYTR competition ECU kit with includes a shorter throttle stop screw.

I'm not a very aggressive rider but I do want all the performance I paid for. If I don't care about remapping the ECU and just want to change out the limit screw for the shorter one, will the stock ECU work OK for the extended throttle range?

Thanks

[yukondood]

you can just remove throttle stop screw without upgrading ECU. Changing over ECU allows for more programs including detuning if you want.

[KennyMc]

Well, you don't want to remove it, you want to get the shorter one ?

[Do I Care?]

Well, you don't want to remove it, you want to get the shorter one ?

+1 removing it will allow the throttle slide to over extend causing damage!

[KennyMc]

+1 removing it will allow the throttle slide to over extend causing damage!

Yeah, like sticking WFO

[Do I Care?]

Yeah, or this.... https://www.thumpertalk.com/topic/127978-broken-throttle-slide-plates-aka-direct-metal-injection/page__hl__%20slide%20%20broken

[vlxjim]

There is more to what is said here. First you can remove the stop screw and just replace it with a short screw. But you still will want the GYTR competition ECU. Thats what Yamaha call it. But its just a non EPA compliant ECU (the non USA WR's come with a programmable ECU without the US EPA map). My dealer tells me that it's the Canada ECU. But I did not look that up to see if it was true. Were the GYTR competition ECU can be programed it also comes with a much better base map. By just installing the GYTR competition ECU the WR becomes a bat out of hell. There is a big difference as the stock ECU starves the bike to lower the CO emissions. I did buy the programer and did use the Yamaha map that smooths out the power (more electric feel). The GYTR competition ECU does come with the short screw to plug the hole where the stock stop screw came out. Yamaha says it's to keep dirt out of the housing. And this is not like the older non FI WR's where you did need a shorter but not too short of a screw.

So you don't need the ECU but the bike will start and run like it was built to run. And Yamaha knew this, and that is why the GYTR competition ECU is only $100 (it's one of the lowest cost ECU's, replacement ECU for all other bike cost 3x that). Its was to get around the EPA, a loop hole. On the older WR's you could just cut a wire and the EPA caught on to that.

Edited May 29, 2013 by vlxjim

[tomerb]

+1 removing it will allow the throttle slide to over extend causing damage!

The 2012/2013s FI bikes do not have a slides they have a butterfly.

[Do I Care?]

The 2012/2013s FI bikes do not have a slides they have a butterfly.

It was an example, butterfly or not it can cause damage removing the throttle stop screw!

[tomerb]

It will not cause any damage by removing the screw, unless the new found power causes damage to the rider!!

[vlxjim]

It was an example, butterfly or not it can cause damage removing the throttle stop screw!

Not true, the Yamaha supplied stop screw that comes with the GYTR competition ECU kit is only 1/4" and is to keep dirt out only. It does not touch anything just plugs the hole.

Edited May 30, 2013 by vlxjim

[tomerb]

Not true, the Yamaha supplied stop screw that comes with the GYTR competition ECU kit is only 1/4" and is to keep dirt out only. It does not touch anything just plugs the hole.

At least two of us knows this!!

[MyersAvionics]

Is there a guide out there on how to remove this screw? I just bought a new 2013 WR450F and ordered the ECU with it, but it's on back order and won't be here until late November. However, i'm racing this Sunday and would like to remove the screw. I know you need a safety torx type screwdriver to get at it, but i'm looking through my service manual now and i haven't been able to locate anything on it.

 

Sounds like it would be easy to take it out and replace it with a short screw to plug the hole.

[MyersAvionics]

Or, is this short picture thread accurate? http://www.dirtbikeworld.net/forum/showthread.php?t=95627

[FORMA MOTO]

http://www.advrider.com/forums/showthread.php?t=845628

[MyersAvionics]

http://www.advrider.com/forums/showthread.php?t=845628

Yup, i read that one first, great guide, but i couldn't tell exactly where the screw was located. Looks like it's just on the very bottom center of the throttle body. I just would like confirmation.

[funt]

http://i1126.photobucket.com/albums/l607/r1alvin/4C46D59E-9267-425A-914D-D3CAA433F309-27437-000014D13DBC1D4E.jpg

 

Not my pic, hope he doesn't mind.  I rotated the throttle body like in the link Krannie posted.  You might have to prop up the gas tank to get a hand on the throttle body to rotate it.

[MyersAvionics]

I was able to get it off on my lunch break. Just took off the exhaust and got it off pretty easily. Pretty packed in there around the F.I. 

 

Made a huge difference with the throttle. 

 

Thanks for the help! : )