| Author | Message | ||
     Squish |
On Buell 1125 bikes, why is it a common modification to remove the solenoid that hooks up to the linkage to the throttle butterflies? (Modification was called “Denoid” or “De-noid”.) What was the reason again? I believe the reason was performance related, but what are the specifics? (After the solenoid is removed, a resistor plug is then plugged into the wire harness which was previously plugged into the solenoid before the "Denoid" procedure.) Thanks. (Message edited by Squish on September 09, 2016) (Message edited by Squish on September 10, 2016) | ||
| Stevel |
The solenoid, when activated, reduces applied throttle to meet EPA noise regulations. The solenoid activates just as the engines starts to produce maximum torque. Consider the case when passing a slow truck you apply full throttle and just as you get about even with the cab, the computer decides you are making too much noise and backs off the throttle. I believe that could easily ruin your day. | ||
| Jc1125r |
Please tell more about the resistor plug. | ||
| Squish |
Stevel, thank you very for the technical reason for the solenoid on the 1125s. John | ||
| Squish |
JC, The resistor plug tricks the ECU into (I believe) sensing the solenoid is still in-place following the denoid procedure; the resistor plug stops the ECU from turning on the CEL (Check Engine Light) blazing bright 100% of the time. The CEL will still apparently come on when maximum engine torque is called for (which relates to high noise levels), such as in 3rd gear under WOT and above 4,500 rpm, but the CEL only turns on for a short time transients with the resistor plug in-place. The resistor plug is an inexpensive part (~$6.00) available through HD and EBR; the HD part number is Y0248.1AM. Below is a link to an old message post on the “Denoid” procedure. The resistor product packaging bag is shown with the HD part number. There is discussion about the resistor plug functions in the later posts in the message thread. http://www.badweatherbikers.com/buell/messages/290 431/490767.html (Message edited by Squish on September 09, 2016) | ||
| Terrys1980 |
The resistor plug is only needed when using a stock ECM. All race ECMs do not throw a code. | ||
| Jc1125r |
Is there a reason that the cable could not be disconnected, yet leave the solenoid connected? | ||
| Froggy |
If you have the Race ECM, you don't need to do anything further as the ECM doesn't trigger the solenoid at all. The cheapest/easiest way to denoid is to just disconnect the pulling cable, as that way when it does trigger it doesn't close the butterflies, and the ECM is none the wiser so no check engine light. Some report that the throttle is easier to operate after disconnecting the solenoid, I've personally not noticed a difference (still have it hooked up on one of my two 1125s). | ||
| Zac4mac |
Ah Frank, but the ECM IS wiser. If it doesn't see a change in the IAC, it DOES set a DTC. All moot with a race ECM. Z I have even pulled the damn thing off my RS Carbon! (Message edited by zac4mac on September 11, 2016) | ||
| Squish |
Zac, I think you meant to say the denoid of the Solenoid / Cable (AKA the “Active Intake”) from the throttle bodies is recognized by the wise ECU. The IAC (Idle Air Control) and the Solenoid / Cable for the “Active Intake” are 2 different items in the throttle body system. According to BWB member Avc8130 the ECU will flag the error when reduction to max torque (which relates to unacceptable noise levels by the EPA) is commended by the ECU, the command is not followed (do to denoid, the throttle butterflies can no longer be partially closed and max torque is observed by the ECU via the engine sensors), and the ECU temporarily turns on the CEL. In the posted denoid procedure at the link below, member Avc8130 noted, that at CEL does come on when torque limiting is requested by the stock ECU, (i.e., the solenoid) but the “denoided” throttles do not limit the throttle as the solenoid/cable are deleted; Avc8130 stated “...4500 rpm, 3rd gear and I wacked it WOT. CEL bright and blazing.” So based on what Avc8130 discussed, the ECU apparently does flag an error/DTC and turns on the CEL temporarily. (But, the resistor plug prevents the CEL from being on all the time.) http://www.badweatherbikers.com/buell/messages/290 431/490767.html John (Message edited by Squish on September 19, 2016) | ||
| Panshovevo |
My 2008 1125R has the cable disconnected with the solenoid in place, and a stock ECM w/a PC 5. I haven't ridden it much at all, but haven't seen an engine light or code yet. | ||
| Azxb9r |
The solenoid is very large and heavy. If you are going to disable it, you may as well remove it, it is a couple pounds mounted up high on the bike. If I remember correctly the solenoid only worked in third gear. | ||
| Zac4mac |
If you never go WFO in 3rd at 5800rpm(IIRC) you'll never set a code. If you do, the ECM will say fire the noid, the TPS sensor will not see movement then a code sets. Not really a big thing as a code doesn't affect running at all unless it's an overtemp. then you get skip spark. Squish - you were correct, I meant to say the TPS, not IAC, earlier. Z BTW, the CEL is only lit when you have an active error and a little longer than the other lights on the dash when you first turn the key on. If you have historics. (Message edited by zac4mac on October 04, 2016) | ||
| Panshovevo |
If memory serves me correctly, the CEL stays on for 4 seconds after the switch is turned on when no historical codes are stored, and for 8 seconds when codes are stored. (That's a big if...) |
