I was hoping to gather some info. Im having a hard time understanding the whole trigger wheel,trigger offset .
So heres what I know (I think) Skip teeth= # of teeth between tach signals, Delay is # of teeth after first tooth after skip tooth tach signal, Trigger offset is basically a fine adjustment for timing. im running a 36-1 trigger wheel on a 2 cyl 2 srtoke I want fixed timing @ 16 degrees.
Cyl #1TDC is @ the 19th tooth Cyl # 2 is @ 2nd tooth after skip tooth. So I would want my skip teeth to be 18, which would fire #1 cylinder correct? but i dont understand how to fire cyl #2 so soon after skip tooth. If someone could explain this to me I might have to buy you a beer.
Thanks
Lewis
2 stroke and trigger
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Read the manual to see if your question is answered there before posting. If you have questions about MS1/Extra or MS2/Extra or other non-B&G code configuration or tuning, please post them at http://www.msextra.com The full forum rules are here: Forum Rules, be sure to read them all regularly.
Read the manual to see if your question is answered there before posting. If you have questions about MS1/Extra or MS2/Extra or other non-B&G code configuration or tuning, please post them at http://www.msextra.com The full forum rules are here: Forum Rules, be sure to read them all regularly.
Re: 2 stroke and trigger
how much trigger offset do you need 100 ,200,300 some one please explain.
Re: 2 stroke and trigger
How many degrees is it between cyl.1 and cyl.2.
You might want to read this post which has a pretty good explanation of the trigger wheel set up.
http://www.microsquirt.com/viewtopic.php?f=89&t=22881
You might want to read this post which has a pretty good explanation of the trigger wheel set up.
http://www.microsquirt.com/viewtopic.php?f=89&t=22881
Re: 2 stroke and trigger
180 degrees between #1 and #2
Re: 2 stroke and trigger
Are you saying that tdc for #1 is 19 teeth after the missing tooth. If # 2 is 2 teeth after the missing tooth then #1 should be 20 teeth after the missing tooth(2 +18 teeth which would equal 180 deg on a 36 tooth wheel =20.
Did you read the post that I linked to? Another question, why do you want to run fixed timing on a 2 stroke. Kind of defeating the purpose of using a computor to control the ignition.
Did you read the post that I linked to? Another question, why do you want to run fixed timing on a 2 stroke. Kind of defeating the purpose of using a computor to control the ignition.
Re: 2 stroke and trigger
Old guy thanks for your reply. I did go to the link it was some what helpful and a little confusing.the reason for the fixed timing the original setup ( points) the timing was fixed at 16 degrees. I just didnt want to deal with advance tables at this point till I get the fuel end of it figured out. If you must know Im at Bonneville right now.I did get the bike to fire and run before i left but not very well. Anyhow am i to understand more negitive offset is better. i guess what i dont understand how can you negitive offset both tach signals or is this one of those things thats simple and im just missing it .
Re: 2 stroke and trigger
If you tell me which tooth is lined up with the pickup at tdc on each cylinder, I could tell you what your settings should be in Megatune. Did you read in the post about when I had the ignition on a test stand. Can,t get a much better explanation than that.
To answer your question the trigger offset moves both cylinders the same amount. If you would post your MSQ we could probably figure our what is wrong with your settings.
By the way, what kind of engine are you working with. I would assume that it is a motorcycle engine.
To answer your question the trigger offset moves both cylinders the same amount. If you would post your MSQ we could probably figure our what is wrong with your settings.
By the way, what kind of engine are you working with. I would assume that it is a motorcycle engine.
Re: 2 stroke and trigger
Yes its a motorcycle , Land speed bike. I rechecked the timing and its the 2nd tooth after missing is TDC#2, 20th tooth after missing tooth is TDC#1.
Just so we are on the same page the first tooth after missing is considered tooth #0 correct? if are we counting actual teeth? Then the above statment is true.
I did read the link you sent me. It helped me understand the teeth but not negitive offset but as you said it applies it to both cylinders right? This may sound stupid but does'nt all the processing of the teeth have to be done before you get to missing tooth again. Isnt first tooth 0 so it starts over or is it more of a reference signal. OK I think I'm starting to see the big picture now! Skip teeth 18, Delay 1, Trigger offset would be 360 degrees -16 degrees before TDC=
negitive offset of-344 degrees please let me have amen on that one.
Just so we are on the same page the first tooth after missing is considered tooth #0 correct? if are we counting actual teeth? Then the above statment is true.
I did read the link you sent me. It helped me understand the teeth but not negitive offset but as you said it applies it to both cylinders right? This may sound stupid but does'nt all the processing of the teeth have to be done before you get to missing tooth again. Isnt first tooth 0 so it starts over or is it more of a reference signal. OK I think I'm starting to see the big picture now! Skip teeth 18, Delay 1, Trigger offset would be 360 degrees -16 degrees before TDC=
negitive offset of-344 degrees please let me have amen on that one.
Re: 2 stroke and trigger
Just to double check you said when you adjust offset it does it for both cylinders. Then why in advanced ignition option they give offset for #2 or is this in case you would want to vary the timing to #2 so it should be left at 0 or should it be set the same as on the general page.
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Re: 2 stroke and trigger
I looked at your msq and saw a few things wrong.
1 The tach signal masking is wrong. From the Megamanual.
For wheel decoding an M-N crank wheel you must use values close to 0.2 ms and 10%. However, to not break any existing setups, the default values are 0 and 50%, the same values that are 'hardwired' into pre-v2.5 code. Be sure to adjust these values when you set up for a trigger wheel (note that they are in a separate dialog from the trigger wheel settings)
2 You need to set your ign output #2 TO 180 DEG. This tells tells the unit when to fire the second ignition output, which in your case is 180.deg.
3 You have your delay teeth set to 17 which will fire on the 18th tooth which is 20 deg btdc. Your 20th tooth is lined up with the pickup at tdc. Each tooth is 10 deg, 360 divided by 36 equals 10. If you set your trigger offset to -4 deg you should be at your 16 deg btdc that you want. You still need to verify this with a timing light and adjust with the trigger wizard.
As far as I know the first tooth after the missing tooth is considered #1.
PS This is assuming that your ignition map is set to all zero's.
1 The tach signal masking is wrong. From the Megamanual.
For wheel decoding an M-N crank wheel you must use values close to 0.2 ms and 10%. However, to not break any existing setups, the default values are 0 and 50%, the same values that are 'hardwired' into pre-v2.5 code. Be sure to adjust these values when you set up for a trigger wheel (note that they are in a separate dialog from the trigger wheel settings)
2 You need to set your ign output #2 TO 180 DEG. This tells tells the unit when to fire the second ignition output, which in your case is 180.deg.
3 You have your delay teeth set to 17 which will fire on the 18th tooth which is 20 deg btdc. Your 20th tooth is lined up with the pickup at tdc. Each tooth is 10 deg, 360 divided by 36 equals 10. If you set your trigger offset to -4 deg you should be at your 16 deg btdc that you want. You still need to verify this with a timing light and adjust with the trigger wizard.
As far as I know the first tooth after the missing tooth is considered #1.
PS This is assuming that your ignition map is set to all zero's.