Sparks Ignition Advance Key

[Jdedad]

After installing this Ignition Advance Key on my TRX400EX I lost my low end torque and I can, not feel any difference in top end.. I hit 65MPH with the old key now I fall short of that as well. any ideas?

[zrpilot]

First time I've heard of this happening. I'd call Sparks tomorrow...

I gotta think some thing else is influencing the performance. Jetting? Gas quality? Ambient temps? plug? I dunno???

[Jdedad]

I was thinking maybe 2007 was already advanced and this screwed it up? I sent an e-mail no reply yet.

[zrpilot]

Jdedad, do you have a A/F device hooked up to your 400EX? IF so where is the W/B O2 sensor? What brand? and what Lambda is it running?

[Jdedad]

The O2 sensor is Bosch N/B 4 wire preheated $20, I installed a bung adapter before the slip on $10, the display I picked up on e-bay for $50

http://www.dynotunenitrous.com/store/scripts/prodlist.asp?idcategory=44

[QuadManiac]

If this is a dumb question, I'll apoligize in advance... BUT

I assume that the advance key is simply a stepped woodruff key; so is it possible to install it facing the wrong way, thereby retarding instead of advancing timing?

[08trx400ex]

it is a stepped woodruff key. put mine in 2 days ago. i followed the instuctions found here

http://www.atvriders.com/articles/timingkey400ex.html

make sure that the red tip is out toward you. my only issue was that the instructions say to move the flywheel to the left and it didnt move much if any noticably. but hey, we're talking 6 degrees here. it says to make sure you arent turning the whole motor over but i went ahead and did that anyways figuring it would for sure be all the way to the left then. it did give me my low end baack that i lost from a pipe & filter install, header weld boring, and air box lid removal. just rejetted the carb yesterday. it was so easy once i got the platics off, ugh!

hope this helps.

[07trx400ex]

did give me my low end baack that i lost from a pipe & filter install, header weld boring, and air box lid removal. just rejetted the carb yesterday.

08trx400ex, how did you lose low-end? The extra air from the filter and air box removal should definitely not sacrifice power(at least until your carb gets trashed).

The pipe should not really lose very much low-end unless the header diameter was over 1.75" and the silencer was bigger than 1".

What pipe are you running and what did you do when you "bored" your header tip.

[08trx400ex]

i bored out the welds at the front of the header. i put on a HMF sport series slip on without the spark arrestor or silencer. i removed the airbox lid and put on a K&N filter. it just felt like after i did these specific mods that i was slightly bogged down on take off. it ran fine through the mid range and then back-fired and popped when i got off of the gas whil it was in gear. fine now though after the rejetting and sparks key. went with 155 main and 42 pilot with a 1/4 turn out on the fuel screw. I also had to adjust the idle screw before the fuel delivery correction

[07trx400ex]

That sounds like you had a jetting problem to me. I would not say that you lost power due to improved plumbing. I would say you lost power because the jetting was incorrect for the "mods" you had.