G oog le BadWeB | Login/out | Topics | Search | Custodians | Register | Edit Profile


Buell Motorcycle Forum » XBoard » Buell XBoard Archives » Archive through March 28, 2004 » Race muffler with stock ECM... « Previous Next »

  Thread Last Poster Posts Pages Last Post
Archive through March 16, 2004Opto30 03-16-04  03:42 am
         

Author Message
Top of pagePrevious messageNext messageBottom of page Link to this message

Opto
Posted on Tuesday, March 16, 2004 - 03:44 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

This maybe could be done with 2 resistors and one 5V zener, the power in (12V) is already there. The expensive bit would be the connector.
Top of pagePrevious messageNext messageBottom of page Link to this message

Darthane
Posted on Tuesday, March 16, 2004 - 04:05 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

There are plenty of ways to do it. They're based on the above extrapolation being correct, though, and while it all sounds good I don't really know...(sometimes I'm such a good BSer I fool myself!)

If the ECM pin that's grounding can accept ~200mA you could steal a 5V signal by tapping into one of the other regulated sensors and have the ECM ground the circuit, activate the relay, and supply 5V to the feedback line.

If I had a 12 to play around on I'd monkey with it, but my Firebolt doesn't have one of these fancy doohickies! Just seems like an awful lot of trouble to get rid of what? 8 oz? A pound with the jumper harness? How much does that thing weigh?

See, connectors I might be able to come up with, provided I can get a part number.

Bryan
Top of pagePrevious messageNext messageBottom of page Link to this message

Blake
Posted on Tuesday, March 16, 2004 - 08:55 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

I recall with fair certainty that the exhaust valve is actuated based upon engine speed AND throttle position (WOT I believe), and the valve is either commanded to be open or closed, there are no partially open commands from the ECM. Don't expect any comments from anony on this issue, though you might find a licensed racer who can talk to Henry Duga about the issue.
Top of pagePrevious messageNext messageBottom of page Link to this message

Blake
Posted on Tuesday, March 16, 2004 - 08:57 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Of course he'll simply tell you to use the Race ECM.
Top of pagePrevious messageNext messageBottom of page Link to this message

2k4xb12
Posted on Tuesday, March 16, 2004 - 03:28 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Thanks for the schematic -- apparently, it is a DC motor and not a stepper... This actually makes it a bit more difficult to fake out the ECM. Oh well -- more to think about...



edited by 2k4xb12 on March 16, 2004
Top of pagePrevious messageNext messageBottom of page Link to this message

Stot
Posted on Tuesday, March 16, 2004 - 10:17 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

I wrote some servo control PIC chips a while back, they are DC and their position is determines by a 1-2ms pulse signal with 1ms intervals. A 508A Pic chip could do the job of faking the sensor easily if programmed correctly. My guess would be its open or closed so you will probably only be looking for 2 different pulse signals from the ECM and then pull the hall sensor down for one and up for the other all in real time. Course I ride a 9.

Cya
Stot
Top of pagePrevious messageNext messageBottom of page Link to this message

Opto
Posted on Wednesday, March 17, 2004 - 02:50 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

I don't think the ecm drives the servo directly, info from the flowchart and schematics suggests the ecm applies a ground and the control cct in the actuator then drives a dc motor all the way, and the ecm looks for 4-6V from the hall effect sensor.Then when the ground is lifted the control cct drives the motor all the way back and the sensor reads 0-1V. Will experiment this weekend. Main prob is if I throw a fault code I'll have to wait 50 run cycles for the fault to be cleared before trying plan B.
Why would I want to do this? I want to reclaim that space under the cover for something else.
Top of pagePrevious messageNext messageBottom of page Link to this message

Darthane
Posted on Wednesday, March 17, 2004 - 05:04 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Opto, what are you planning on trying first?
Top of pagePrevious messageNext messageBottom of page Link to this message

Opto
Posted on Thursday, March 18, 2004 - 03:06 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Maybe this would work, when the ecm control goes low C1 will charge up to 5V with R1 and R2 acting as a voltage divider network. When the ecm control lifts the ground, C1 discharges through R2 and goes low. Hopefully this will keep the ecm happy. Component values will have to be tried on the bench before fitting to the bike. Where's Reepicheep?

actsim
Top of pagePrevious messageNext messageBottom of page Link to this message

2k4xb12
Posted on Thursday, March 18, 2004 - 11:17 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Has anybody actually stuck a scope on the motor feed and hall sensor to see what kinds of interaction they have? My Tektronix 475 has recently suffered a high voltage supply failure, so I can't look at the signals myself (this has prompted me to bid on another 475 on Ebay though). The circuit above looks interesting enough -- any idea what kind of charge/discharge time we're looking for in regards to C1? If so, then values should be fairly easy to nail down...

Steve.
Top of pagePrevious messageNext messageBottom of page Link to this message

Opto
Posted on Friday, March 19, 2004 - 02:47 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Steve, C1 charge/discharge time needs to be 0.5 sec or less - just ran the actuator up on the bench. If you can work out some ballpark figures for the cap and resistors that will save me time doing it by trial and error. Thanks, Ian.
Top of pagePrevious messageNext messageBottom of page Link to this message

2k4xb12
Posted on Friday, March 19, 2004 - 11:09 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Well, the rate of charge and discharge will be different, because the value of R1 will determine the charge, and R2 the discharge, and R1 needs to be a bit less than double the value of R2 to get the division we want. The charge/discharge rate is calculated by R*C. For starters, try a value of 22K for R1, 22uF for C1 and 9.1K for R3. This should give a charge rate of approx. .48 seconds and a discharge rate of approx. .2 seconds. Oh yeah, stick a resistor of about 10K on the base of the transistor to limit current.

This is a ballpark, but should give you a starting point...
Top of pagePrevious messageNext messageBottom of page Link to this message

Opto
Posted on Wednesday, March 24, 2004 - 06:16 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Thanks Steve, your info did help. Update: No success yet, ecm not happy, more research and testing required, info from the FM is not the whole story (the "low" from the ecm is 2.5V and the hall sensor O/P is loaded with 5V from the ecm and the hall sensor O/P is not linear, it appears to drive a flip-flop at each end of the actuator travel), will post details in KV when I get it done.
« Previous Next »

Add Your Message Here
Post:
Bold text Italics Underline Create a hyperlink Insert a clipart image

Username: Posting Information:
This is a private posting area. Only registered users and custodians may post messages here.
Password:
Options: Post as "Anonymous" (Valid reason required. Abusers will be exposed. If unsure, ask.)
Enable HTML code in message
Automatically activate URLs in message
Action:

Topics | Last Day | Tree View | Search | User List | Help/Instructions | Rules | Program Credits Administration