14-5 triggerwheel can it be done?

[pirus]

Hello to all. My first post here. Im doing a Fuel Injection project on my 1-cylinder Honda NX 650 (same motor as XR650L). The existing trigger wheel for the CDI has only one tooth but theres a later motocycle model named FMX 650 that has a 14-5 triggerwheel(9 teeth and 5 missing). Could I use that wheel for my microsquirt? It would be a very easy install if it would because it would fit directly on the existing axle splines. I know its not as accurate as a 36-1 but I will compromise that, remember this wheel is on the crank and the bike fires once on two crank rotations so its basically 28-10 wheel.

Did I make anything clear?

Pictures of existing wheel for CDI and a newer wheel from the FMX bike:

[Matt Cramer]

It will need to run in wasted spark if there's no cam sensor, firing once every crank revolution.

The code will let you try those numbers, but I'm not sure how they'll work in the real world.

[pirus]

It will need to run in wasted spark if there's no cam sensor, firing once every crank revolution.

The code will let you try those numbers, but I'm not sure how they'll work in the real world.

Yes it will be a wasted spark and also giving a spray every revolution but thats how it is, it shoulnt be a problem.

But still we dont know if the microsquirt is going to accept the 14-5 trigger wheel? But there's no where in the manual how many missing teeth there can be? 1 or 2 are most common. I dont even know if there's any significance since it only has events during those teeth that are on the 14-5 trigger wheel.

EDIT: oh I re-read your post, so it will accept those numbers, thats all I need then, going to order the wheel and all the other parts. This is going to be a exiting project! Thanks Matt for you quick answer!

[grippo]

As Matt says, it should work in theory, but has never been done before that I know of. Its not a 28-10 wheel, the missing gap is 5 not 10, so treating it like a cam wheel with 28 teeth would make it 28-5-5 and that won't work.So you need to put it in as a 14-5, single crank wheel and fire spark every 360 crank deg.

[pirus]

Well I read someone using a single tooth wheel and got fuel working, he didnt recommend it to ignition though. The original CDI uses a single tooth wheel in my bike wich is from year 90 by the way lol. Ive never programmed any ignition, I know that this setup will be wasted spark and spray, but I dont think that should matter, its a wasted spark ignition from the factory already. But I havent gotten too much into how much my ignition advance max ít will need. Im gonna try this to keep my bike as stock as possible, so if Im gonna sell it I can still put on the carb and single tooth wheel again and get it going. I havent checked where the first tooth is located to TDC. The enginge will need a revlimit at 8000 so there shouldnt be any problem with dwelltimes. And im keeping it 8000 because i dont want to damage the engine.

[pirus]

Oh, and I might just try to get it working with this setup and the see if Ill put a camsenstor on it, I saw another thread of a guy adding that to his endurobike.

[pirus]

Do these look correct then?
Triggel Wheel Teeth 14
Missing Teeth 5
Skip Teeth 0 (since theres only 1 tach per revolution?) or should it be 14?
Delay teeth 5

My concern is more the skip teeth.

[Matt Cramer]

Skip teeth needs to be 14.