Just want to post another in a seemingly long series of posts regarding servo motors and HTEV valves, flapper valves, etc.

After getting the '35' code and doing a bunch of research, I disassembled the HTEV valve to get an understanding of how it worked. Turns out that the HTEV valve was so carboned up, it would not turn unless you physically turned it with a pliers, that had overwhelmed the little plastic gear in the servo motor and stripped it out. So I turned the HTEV valve to the full open position, removed the cables from that and the servo, then removed the cable that runs the flapper in the air box. I opened up the air box and completely removed the entire flapper valve assembly (8 screws). Reset the ECU using the service manual procedure and have very positive results. The bike breathes better (with the flapper not working correctly, it was 80% blocked all the time) and it exhausts better (with the HTEV to the 90° position, it was 50% blocked, kinda like putting a potato in your tailpipe). It sounds better/deeper, the RPMS's spin up faster and there is no negative issue, it runs perfect. The ECU 'learns' and adjusts the fuel mapping to match the new air flow, so I will be getting slightly less mileage, but way worth it. In the future if I notice any 'seat of the pants' dead zones in the RPM range, I may opt for a Power Commander, but at this point, this was all free and made my code go away and the motor is free to breathe finally.

 

How does the ecu learn and adjust the fuel mapping?

 

Well, thank you sir. I now know what I am going to do tomorrow. I've had the same problem, but dammit I'm tired of tearing that bike up and down...

Good work, I'll let you know how mine goes!

 

I've been debating pulling mine out too.. Dont know if anyone else feels it, but if im jus cruising in a high gear low rpm, when i hit 3k rpm where the valve opens/closes it gets jerky on me..

 

Wish I could say for sure, but my problems seem so many that I can't be certain that's the exact cause.

My biggest issue, aside from the tranny, is basically the bike won't rev past 10,5K RPM's. No matter what gear, no gear - nothing.

I was thinking that mine just is stucked almost closed or something. Because isn't there only two positions on it, right? running, and WOT?

I dunno - hope it solves my problem, lol. Wish I could get my new tank and upper painted and get everything on it man, sucks...

 

 

Anyone already done this with a pc3. I would guess you could use a map for a full exhaust right? What about a pic of the inside of the exhaust valve. I seem to remember one posted last year but couldn't find it. Would it be feasible to gut the thing out, weld up the holes where the shaft goes in. A makeshift eliminator so to say. While all thats apart, what about the cone, take it out too??

 

The EPROM chip that is the brain of the ECU, is constantly 'learning' and adjusting for your bike based on air intake/volume/humdity, etc.....that is part of the entire fuel injection package (i.e. we don't need a choke because the ECU automatically does it for us, then knows when to adjust it based on internal engine temps). It can only adjust so much though, so some folks opt to go to a Power Commander to put the finishing touches on the RPM ranges that are not completely dialed during the manufactureof the ECU.

NY Erion929 displayed a great picture of how the exhaust flow works at specific RPM ranges. Unless you are at full honk, the HTEV valve is partially closed when everything is working the way it is supposed to. My HTEV would not move at all and was stuck at 90° (50% blockage). Went for a spin yesterday afternoon and also commuted this morning and the bike is right on the money.

 

Leaving the guts in makesa little more sense as it would have a better air flow. If you took the valve out of the body, it leave a lot of areas for air to bounce around in and you would still have to weld the outside closed. Just remove the cables and leave the cover and bracket. The HASS eliminator does all this for you for a price, it reduces weight as well....but for the budget minded, this accomplished the exact same thing.

 

Yep, I'm guessing that's my exact problem, then.

Thanks you two - like I don't have enough to do...