Black Box Does It Go Bad?

[jpd]

i dont know how too tell if the box is bad or not my bike is acting real weird it will start up fine but then it dies out a few seconds later or only one side will fire

[jpd]

my motor has just recieved a new top end 50 over with a cool head 18cc domes stock carbs 290 main throttle electronics disconnected K&N filters T5 pipes and silencers barnett clutch timing has been advanced flywheel lightened no porting yet and various cosmetics but will not run right does not even have a hour on motor. did a few heat cycles then it started this not wanting to fire on left side thing. took carb apart cleaned and cleaned again still no results could it be coil? pulled plug ang am getting spark and fuel what gives?

[2001SSTBanshee]

Unfortunately, theres no phisical way to "test" your cdi. The only thing you can do is swap with one that is definately working and see if works right.

 

Kinda sound electrical to me

[sredish]

what year is your bike? if your getting consistent spark, then it's not the cdi. check your compression to verify the coolhead is sealed and the top end is tight. who did the top end and what parts are new and what parts did you have before? Generally, with my little experience anyway, when the cdi goes bad, there is nothing, no more starting, not even a puff here and there, goes bone dead.

 

Do me a favor and double check your spark to reconfirm that you are getting consistent spark on both plugs, and do a compression test. are your carbs sliding open and closed easily, or are they sticking at all, check that. how advanced is the timing?

 

Check all that and get back.

[jpd]

my bike is a 2001 all top end parts weisco piston, clips, wrist pin, bearings came in a kit with cometic gaskets. also replaced all o-rings in cool head i do not have a compresson tester right now but i have a friend that has one and also a banshee that i can try swapping out cdi with if he will let me

[sredish]

but i have a friend that has one and also a banshee that i can try swapping out cdi with if he will let me

that will be a quick way to rule out the cdi. I'm just worried about your compression, don't know why, but I would just try to get that checked before you go too deep.

 

You say your "getting fuel". Are you sure it's getting into the motor? Are your reeds in good shape? Did you check your carbs? Pull off the air filter and look in from there to see how the slides are.

[Yaxy]

This is going to be confusing so bare withme on this. I have an 89 banshee and have gone through 3 CDI's since 1990. Let me tell you they are one big pain in the but, and the results of a box malfuncitioning are wide spread.

 

my 1st box, bike was idling at warm up and then just died no spark, Ok I had an extra 89 at the time so that was easy to figure out.

 

Please note jetting has been the same for 5 + years so I automatically rule it out when there is inconsistancies in performance

 

 

2nd box, (Yamaha brand box) If temp was under 70 degrees no issues. IF above 70 the bike wuold run great for about 20 minuts then start to break up bad before the powerband. Let bike cool for a few hours start agains and same thing, 20 minutes then run like crap.

 

Now if under 70, ride all day no issues ran perfect.

 

3rd box, ran a Dyna for 3 months had similiar issues to box 2 to happend all the time though, break up Covered under warranty.

 

4th DYna 1 year old and still working fine.

 

Bottom line. IF you are sure your jetting is right and are confident in your abilities to tune, any issues in my opinions and experiences are related to the CDI.

 

Chris

[sinkorswim]

I agree with chris I had one retard itself. It would start hard then when you did get started it would backfire. the best way to check is swap or rule every other thing out with a multimeter. believe it or not if a coil gets warm and it is bad. it will lose continuity and die also.

Adam