rocket racing cdi trouble help
- Thread starter ronorcal
- Start date
Likely the magneto coil is bad and not the cdi. Since you own and aftermarket CDI can I assume you still have the stock CDI? If so swap CDI's and see if it solves your issue. If it doesn't I suspect it is a bad coil or a bad wire connection.
You can test the coil with multimeter. The coil should read 300 to 400 ohms of resistance while the test meter is on the 2k/2000 range. Put the meters test leads firmly on the Blue and Black wires of the magneto coil to get your ohm reading.
You can test the coil with multimeter. The coil should read 300 to 400 ohms of resistance while the test meter is on the 2k/2000 range. Put the meters test leads firmly on the Blue and Black wires of the magneto coil to get your ohm reading.
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Here you go! scroll down and look at the pictures attached for the item.
Looks just what you need.
http://www.ebay.com/itm/ROCKET-Raci...D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557
Looks just what you need.
http://www.ebay.com/itm/ROCKET-Raci...D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557
TheNecromancer13
Active Member
How many wires are coming out of the CDI? 2, right? So it wouldn't take too long to try all possible wiring combinations until one works. That's what I did when the wiring instructions turned out to be wrong.
Davezilla
New Member
I had the same trouble when I bought a Rocket CDI to test out last summer.. no spark no matter what I tried, tried a known good magneto coil and even wired my stock CDI back in and it fired with ease, wired the Rocket back in and Nothing.
I finally found the culprit to be the wires were soldered in backward so when I reversed teh black and blue wires it fired right up. Try this by doing a spark test with your plug out of the engine, you can spin the engine with a cordless drill and a 14mm socket on the mag rotor nut, this won't hurt anything with the plug out, but drill starting these engines will strip that little mag nut... I found that out by experience then replaced that thin nut with one that's regular thickness so it has 3 times the thread contact on the threaded shaft end.
Try reversing the wires and also make sure your black wire to the coil is properly grounded to the engine or your frame, if there's a poor ground contact or if it's not making contact to ground it also won't spark. There's also the possibility the wires going out from the cdi to the mag coil could be reversed so try the wires from the mag to cdi, then from the cdi to the coil and it will fire if one of the 2 wire sets is soldered in backward.
I finally found the culprit to be the wires were soldered in backward so when I reversed teh black and blue wires it fired right up. Try this by doing a spark test with your plug out of the engine, you can spin the engine with a cordless drill and a 14mm socket on the mag rotor nut, this won't hurt anything with the plug out, but drill starting these engines will strip that little mag nut... I found that out by experience then replaced that thin nut with one that's regular thickness so it has 3 times the thread contact on the threaded shaft end.
Try reversing the wires and also make sure your black wire to the coil is properly grounded to the engine or your frame, if there's a poor ground contact or if it's not making contact to ground it also won't spark. There's also the possibility the wires going out from the cdi to the mag coil could be reversed so try the wires from the mag to cdi, then from the cdi to the coil and it will fire if one of the 2 wire sets is soldered in backward.
MotorBicycleRacing
Well-Known Member
The eBay link to where it iis sold is In this thread.
Aftermarket parts hsve "racing" in the name to appeal to dumb buyers.
There are 5 CDI's being made now as "upgrades"
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Although the rude response was edited out of the above post the content is correct.
Anytime you see the words, 'Race' or 'Racing' ot 'High Performance' or 'Speed', beware.
Those words and similar ones are used to entice the unsuspecting buyer into believing the product will increase performance. "Made of billet" is another catch phrase or 'buzz words' that many people fall for. Buyer beware.
Tom
Anytime you see the words, 'Race' or 'Racing' ot 'High Performance' or 'Speed', beware.
Those words and similar ones are used to entice the unsuspecting buyer into believing the product will increase performance. "Made of billet" is another catch phrase or 'buzz words' that many people fall for. Buyer beware.
Tom
Davezilla
New Member
The real problem is that you can only get out the same power you can put in with these ignitions regardless of coil size and type, basically whatever your mag rotor and coil can feed into a cdi and coil can not be boosted so a bigger ignition coil wont give a stronger spark unless the voltage andncurrent coming from the mag coil is stronger. A stronger magnet rotor helps as well as antighter gap between the rotor and stator and more windings on the mag coil is where the improvement needs to start at. Some magnets are pretty weak right out of the box and others are really strong, if you got a nice strong magnet rotor you'll have more spark energy. With more spark energy a better coil could be used as well as a wider gap at the plug to take advantage of the increased spark energy.... there is a decent amount of power hidden in the ignition system and when someone comes up with a better mag rotor and coil combo then some of these aftermarket cdi's that use motorcycle or dirtbike coils may be a lot more effective. Selling an aftermarket cdi setup to a customer that has a weak mag rotor will just convince that customer he just got took with another gimmicky part. The other alternative would be to convert to a battery powered coil and better points or cdi type ignition that could offer a hotter and stronger spark to go with the improved timing curves. The timing curves also need to be variable in a wide enough range that can improve a well built engine as well as a stock engine... the only problem here is if the customer don't know what they're doing and set their timing curve too hot for their setup then they'll be convinced that brand x cdi just ruins engines. Or when the timing curve is fixed and not adjustable by the end User, most customers will experience less power depending on how their engine is set up.
So if the timing was variable either by a rotatable stator plate or by a trim pot on the timing cap in the cdi your Kinda stuck with what you got.
The Jag cdi uses jumpers to offer more timing curves, but none of these curves are aggressive enough for real.performance, the HD lightning cdi is sealed so the end User cant change any of the internals out, the Rocket cdi is based on the "roll your own cdi" thread and the components are easy to get to and swap out to customize a spark curve but there's only a small handfull of us that could successfully do this without running into detonation from too much spark advance for the compression ratio and fuel quality etc...
mapbike
Well-Known Member
I've run the Jag type CDI, the HD's Lightening CDI, the Rocket CDI and several stock kit CDI's
Results are, Jag type with timing retarded ran fine but I lost 6mph from my top speed compared to the stock unit.
Rocket CDI gave sililar results as the Jag, ran OK, but lost top speed due to the timing being retarded.
HD's Lightening CDI, I am still running this one on one of my bikes, it was one of the first hand full Daniel made that has the unlimited timing,it's not sealed with epoxy, no timing retard and this one has done a great job, it didn't add any noticeable performance gains, engine runs the same with it as it does with the stock unit, It has a cool key switch feature that I like, but again no performance gains over the stock unit but also no losses either like I experienced with all the others I tried.
Another thing I'll add here is that the claim that some give about making the engine run smoother are the words of a snake oil salesman, the vibration issue with the engines that shake rattle and roll is because of an untrue and badly balanced crankshaft and no amount of timing advance or retard can remedy that.
My suggestion is if you have money to burn and you just gotta have an after market unit, get the HD's Lightening, if yoy want something that will make your engine run exactly the same then just keep the one that comes in your engine kit and replace the spark plug & Boot for an NGK and you'll be good to go.
Results are, Jag type with timing retarded ran fine but I lost 6mph from my top speed compared to the stock unit.
Rocket CDI gave sililar results as the Jag, ran OK, but lost top speed due to the timing being retarded.
HD's Lightening CDI, I am still running this one on one of my bikes, it was one of the first hand full Daniel made that has the unlimited timing,it's not sealed with epoxy, no timing retard and this one has done a great job, it didn't add any noticeable performance gains, engine runs the same with it as it does with the stock unit, It has a cool key switch feature that I like, but again no performance gains over the stock unit but also no losses either like I experienced with all the others I tried.
Another thing I'll add here is that the claim that some give about making the engine run smoother are the words of a snake oil salesman, the vibration issue with the engines that shake rattle and roll is because of an untrue and badly balanced crankshaft and no amount of timing advance or retard can remedy that.
My suggestion is if you have money to burn and you just gotta have an after market unit, get the HD's Lightening, if yoy want something that will make your engine run exactly the same then just keep the one that comes in your engine kit and replace the spark plug & Boot for an NGK and you'll be good to go.