Upgraded and now it won't start

Motocruiser

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kansas City
So I just recently got all of my upgrade parts in. Includes: SBP expansion chamber, pirate cycles 44 & 36 tooth sprockets and hub adapter, jaguars CDI, a CR-80 coil and Dellorto SHA 15.15 carb. It ran fine a couple times down the street then died. I unhooked my kill switch, no fire. I replaced the spark plug and plug wire, no fire. Took the CDI apart to check internal wires, all fine replaced, no fire. Next step is to go through all of the wires to make sure they aren't grounding out somewhere. If that fails I guess I'm gonna order a new magneto. Any other suggestions from anyone?
 
So I just recently got all of my upgrade parts in. Includes: SBP expansion chamber, pirate cycles 44 & 36 tooth sprockets and hub adapter, jaguars CDI, a CR-80 coil and Dellorto SHA 15.15 carb. It ran fine a couple times down the street then died. I unhooked my kill switch, no fire. I replaced the spark plug and plug wire, no fire. Took the CDI apart to check internal wires, all fine replaced, no fire. Next step is to go through all of the wires to make sure they aren't grounding out somewhere. If that fails I guess I'm gonna order a new magneto. Any other suggestions from anyone?

I'm guessing if you got a new CDI and placed it on your bike it may be the problem. Check if you matched the colors correctly. (blue to blue)(black to black) and the two coming from the kill switch can go in either of the left over holes from the CDI. If you mess up the (blue to blue)(black to black) you can destroy your CDI unit.

Might sound silly but also check for air leaks, carby Inlets, exhaust outlets and the carby itself. basically where air could get in or out that you dont want it to. makes your engine cut out and you mistake it for a sparky fail or wiring mistake

here is a trouble shoot guild for the standard CDI which may help:

http://www.youtube.com/watch?v=89rdCnMUpek
 
I'm guessing if you got a new CDI and placed it on your bike it may be the problem. Check if you matched the colors correctly. (blue to blue)(black to black) and the two coming from the kill switch can go in either of the left over holes from the CDI. If you mess up the (blue to blue)(black to black) you can destroy your CDI unit.

Might sound silly but also check for air leaks, carby Inlets, exhaust outlets and the carby itself. basically where air could get in or out that you dont want it to. makes your engine cut out and you mistake it for a sparky fail or wiring mistake

here is a trouble shoot guild for the standard CDI which may help:

http://www.youtube.com/watch?v=89rdCnMUpek

I appreciate the reply. I had the wires correctly hooked up as it ran previously. I don't have a stock CDI so the video isn't going to help. I have a modified KDX200 CDI by a forum member Jaguar. Not thing I'd different in the setup except the exhaust and carb. So I suppose I should go back to stock to see if that was the problem.
 
Hello,
I bought (pirate cycles) the same carb as you and installed it over the weekend on my 66cc grubee engine. I'm pretty sure I know whats wrong! Hehe
The mixture is to rich for the engine. I'll tell ya my experence.
After the install, the bike would not start, you could tell it wanted to. After thinking a couple of min's, I took out the air filter and removed the carb cover ( Give it more air). It started without the choke on!! Now this told me the engine was running WAY to rich!
The engine needed more air, and I had a stock exhaust on it. I took off my stock exhaust and had an extra straight pipe laying around (Stock exhaust with the muffler cut off). After switching exhausts it took off like a rocket! Still won't start with the choke on, which tells me it's still running rich.
I went online the other night to a moped site that sold these carbs and it warned not to install this carb unless you have done MAJOR mod's (Intake, exhaust, piston, etc)... You need to lean out the mixture. (Probably)

Good luck :)
 
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I missed the part about no spark... Well, maybe it's not the carb. I did get my CDI from Jag the other day, but have not installed it yet. I would like to know how it works out for ya.
 
The CDI worked fine. Its a subtle change but I never had the opportunity to try it with lower gearing or my SBP expansion chamber because it stopped working. I then returned the bike to stock and it still won't run.
 
Good Point Al,
I installed my carb, then made sure the bike started. I didn't care if it ran like **** at that point. Then I installed my high compression head. Next, I will install my new ignition parts, then my expansion chamber. Then fine tune the carb.
I learned the hard way about doing one thing at a time. I used to fix old tube radios. When I first started, I would change multiple parts, then plug it back in. One time, I did this and the radio didn't power up.... Wow, what a pain-in-the-neck it was trying to figure out where the problem was! I ended up taking it to a more experience person, and he told me the same thing... One part @ a time! And he fixed radios for a living :)
I wish you the best of luck figureing out what the problem is...
Gas/Air , Spark & Compression = Varoom!
 
People take warning......

Only install one mod at a time and test run between mods/upgrades

exactly!
this allows you to backtrack easily if you run into a problem after installing an upgrade or high performance part.
plus, it will tell you if that part is actually giving you a performance gain or loss.
if you bolt on a bunch of stuff, and then lose 5 mph, now you have to try and figure out exactly which part is causing the loss.
one part at a time and then a test run in between each part will tell you exactly what that part is doing.
if you put on an expansion chamber and gain 5 mph....good.
put on a high flow air filter and gain 1/2 mph ...good.
put on a high compression head and gain 3 mph....good.
put in a champion spark plug and lose 5 mph.....take the plug out and go back to what was in it before.
put all those parts on at the same time without a test run in between, you will never know exactly what's going on.
 
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