Check this out. I wrote the seller asking him if these Big Gun CDI boxes are made by Procomm and expressed my concerns with thier reliability and possible damage to the engine. His response follows:

"Dear Buyer,
This is a box that is built in the factory that builds procoms rev boxes however, Big Gun is the compnay that originally put Pro com into business building these boxes. They gave procom the technology. However on the box it is built in the same factory but big gun uses a different design. Also remember it does not matter if the box fails as big gun warrantys the boxes for one year. Thanks"

Change anybody's opinion? Should I jump on it? It's buy it now for $130. The box is warranted for 1 year, however, no mention of the motor damage being covered should it occur.

eBay item #4583852019 description:

Big Gun Exhaust systems Bombardier DS650 (02.5-05) Big Gun Over Rev Box. This unit increases the rev limit on this machine 1750 RPM over stock. This unit is mandatory if you have any exhaust system of any kind as this box will add another 3 hp over stock and pulls each gear another 50-75 feet. This unit will not hurt or harm your atv engine as the limiter still exists it is just moved up. Big Gun backs and will warranty this electronic item for one year from purchase date! Only company to offer such a warranty on electrical parts. Get yours today and feel the added power instantly over stock!

So this just completely removes the rev limit?
Why can't Ron Wood be in this price range???

 

hmmm sounds like he is just trying to make a sell --man i dont know if i would risk it

 

I bought mine from A&B Extreme right here on thi forum for $107.?? I bought the newest model for my quad, which advances the timing AND increases the rev limiter by 1200. I didn't want to go with one of the +2000 and risk blowing it up. Mine's been great so far, just carry your factory one with you. That was the advice I got for ANY aftermarket cdi.

 

Sure they say they will warant the CDI box. But I'll bet they don't warrant the damage the box does to your one way bearing and the labor etc.....

Rule of thumb:
If it's too good of a deal to be true. It usually is.

 

dont get me started.....big F*cking deal they warranty there box...will they pay for all the damage that happens with sh* t azz boxes....no way, they just send you another box or your 100$ or whatever..

there so full of sh*t...try making a good box and you wont need to promote your warranty only your

quality box..dont go cheap on your CDI you will only pay in the long run...do a search you will see

my opinion Vortex only real option

 

I've heard of dyna boxes going junk and they're 5 times as much as mine. I've heard of people with the expensive ones being junk, and I've heard stories of the cheap ones lasting forever. I went middle of the road on the lower end of things. I heard of the problems with procomm, but not much bad about big gun. I've also heard there was another "big" name made in the same factory, but I don't remember which.

What problems have you guys had, and how was it directely associated with your cdi? I say directely because a lot of the time an aftermarket cdi is added there are other mods such as cams involved. Did you guys have other mods, besides aftermarket exhaust?

 

Hey, I have read the searches on Procom and know about their problems. Yet many of you put the Big Gun in the same boat as the Procom unit because it is built at the same factory. My question is, "how many of you have had a problem with the Big Gun unit?" I run a Big Gun cdi with no problems at all. I would like to know if I should be concerned about the Big Gun causing the same problems as the Procom. I am not concerned as much about a complete failure as my stock unit did just that, so any unit can go bad. Has the advance on Big Gun caused any kickbacks as the Procom did and does. If not it could be that the Big Gun is a more reliable unit. If you run this unit, or know someone who does, let me know how it is working out for you or them. Thanks

 

Ace, I do not think that the pro com or big gun removes the rev limit.
To my knowledge RW is the only one that does.

My question for the others out there who are much more knowledgeable than I is....
"Why can a YFZ rev to 10,200 rpm without engine damage? and Why is the rev limit so low on the Rotax?"

Anyone know?

 

It probably doesn't mean anyting but I run the Big Gun cdi on my sons 450R with no problems.

 

So the rev limit is increased by 1750 RPM. Still safe with a stock motor?
The timing advance is what my main concern is after reading about the starter and bearing problems from the Procomm.
So 400EXerciser and Sparky8370 are the only ones running the Big Gun on the DS? Sounds like Sparky's may be a little different than the one advertised.
The eBay item I'm talking about comes directly from Big Gun down in Rancho. They do business on eBay as fourstrokepipeking, selling exclusively Big Gun merchandise. I got my complete exhaust system from them for $200 shipped. Thought that was a decent deal a couple of years ago.

So, at this point it sounds as though there are no major problems with this CDI. Only a few concerns as to what may happen. I might hit some of the other forums and see what issues if any have arisen on say the V Force or other similar big bore.
Thanks