VEMS Community Forum

Technical => Triggering => Topic started by: Cornelius on August 20, 2018, 05:55:46 PM

Title: v-twin
Post by: Cornelius on August 20, 2018, 05:55:46 PM
Hi, can vems handle odd v-twin? it is kawasaki vulcan 1500cc engine 2 cylinder at 50 degrees. intending to use missingtooth 60-2. How do I settup primary trigger? In my opinion it should be like this https://drive.google.com/file/d/1iM2lJRxt-4Emvpghlbsq0rGdVD9wgnsq/view?usp=sharing (https://drive.google.com/file/d/1iM2lJRxt-4Emvpghlbsq0rGdVD9wgnsq/view?usp=sharing)  but I get lot of errors  :-\ next trigger tooth should be at 310 crank degrees (55 teeth)
Title: Re: v-twin
Post by: jrussell on August 20, 2018, 07:56:16 PM
I anticipate the 60-2 trigger is not factory on that engine? VEMS can easily control the engine, but I'm pretty sure that trigger won't work. You need the firing angle to be divisible by the trigger teeth. A 36-1 would work since it's 50 and 310 (both divisible by 10, and it's 10 degrees per tooth on a 36 tooth trigger). A 60-2 is 6 degrees per tooth, so neither 50 or 310 works evenly. 
Title: Re: v-twin
Post by: Cornelius on August 21, 2018, 11:12:35 AM
you are absolutely right, 60-2 is wrong choice, so the preffered one is 36-1. by factory, engine has two individual vr pickups, for each cylinder, positioned at 50 degree between each other and one tooth on the flywheel.  seems that vems doesn't like odd triggering events, giving errors. For 36-1 trigger type, next  trigger tooth must be 31, but this value gives me same  error described above.
Title: Re: v-twin
Post by: Kamuto on August 21, 2018, 11:38:27 AM
Quote from: Cornelius on August 21, 2018, 11:12:35 AM
you are absolutely right, 60-2 is wrong choice, so the preffered one is 36-1. by factory, engine has two individual vr pickups, for each cylinder, positioned at 50 degree between each other and one tooth on the flywheel.  seems that vems doesn't like odd triggering events, giving errors. For 36-1 trigger type, next  trigger tooth must be 31, but this value gives me same  error described above.
fill wiki page, you will get answer there for sure :)
Title: Re: v-twin
Post by: Cornelius on August 23, 2018, 08:22:40 AM
does anybody know, is there a way to make both trigger inputs to work as primary, triggering separate banks of injectors(ignition) ? the only way, that I've found, to trigger v-twin engine is a bit tricky and consit in fooling ecu(make it think that 2 cyl. engine is 8 cylinder  :o)http://www.vems.hu/wiki/index.php?page=MembersPage%2FElbeEngineering%2FKTM (http://www.vems.hu/wiki/index.php?page=MembersPage%2FElbeEngineering%2FKTM) I think that trigger settings should be more flexible, to avoid such tricks.
Title: Re: v-twin
Post by: Kamuto on August 23, 2018, 12:15:43 PM
Quote from: Cornelius on August 23, 2018, 08:22:40 AM
does anybody know, is there a way to make both trigger inputs to work as primary, triggering separate banks of injectors(ignition) ? the only way, that I've found, to trigger v-twin engine is a bit tricky and consit in fooling ecu(make it think that 2 cyl. engine is 8 cylinder  :o)http://www.vems.hu/wiki/index.php?page=MembersPage%2FElbeEngineering%2FKTM (http://www.vems.hu/wiki/index.php?page=MembersPage%2FElbeEngineering%2FKTM) I think that trigger settings should be more flexible, to avoid such tricks.
vems trigger settings probably are most flexible from ecus I know ;)
Title: Re: v-twin
Post by: jrussell on August 23, 2018, 03:05:22 PM
I don't have time to set this up for you, unfortunately, but it's done with trigger reference tooth table. In your case it would be something like 5, 31, 5, 31 (or maybe 1,27,1,27 if you want first trigger tooth to be 1 instead of 5. You just add or subtract from both the same so they are always the same distance from each other)

You don't need two triggers.