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Hello all, first post on here. I am a trained and skilled mechanic with 20 years field experience for the most part i have enough experience to get myself in and out of trouble I mostly read through posts for ideas and suggestions when i have more than one thought about something, but i am looking for someone that has used a dynatek cdi on a 660 grizzly. I bought one and installed it on my 02 660 but have not run it yet i am waiting to get my clutches back from airdam currently. My concern is the 9000 rpm rev limiter. I realize under load with the CVT it's not going to max out every time i punch it but that's a huge increase from 7700 has anyone experienced problems or blown engines due to this? I'm not planning on holding it wide open down the road but..... Some input would be appreciated.
 

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Welcome from Colorado.
I remember old thread on this, but it seem those threads are gone due to age.
From memory, I don't remember a 9,000 r.p.m. limit available for the 660.
 
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Thank you! I was not sure if i would get much feedback due to the age of the machine, although it looks brand new still! That's what the instruction papers said it would raise it to, I was surprised to see it that high. I emailed dynatek to see if they would reprogram it if i sent it back, they told me once the map is plotted it cannot be changed. Not sure what to do at this point, if i could put a programmable shift light on it for 8300 rpm if it came on i would back out of it but can't find one for a single cylinder
 

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Do not over think this. The Dynatek CDI was a common mod for the 660 years ago. Thousands have been installed and ran without issue. In most cases, you will run out of clutching before you run out of RPM.....unless you go stupid aggressive in your clutching.

You'll feel it or know it if your revving higher than you should be. The only guys I knew that kept hitting max rpm were the mud racing guys. They don't care about a 60 mph top speed. They only cared about turning those 30+ inch mud tires in whatever conditions demanded. 0 to 30 mph wheel speed is all they needed.

The best thing about the Dynatek is that it removes the reverse speed limiter. It also advanced the timing 4 degrees if I remember correctly. If you run a high compression piston of 11:1 with a Dynatek CDI, you will need to run race gas or race/pump gas mixture in order for it to survive (with the 11:1 alone, supreme 91 plus octane is all you need).
 

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Thank you for the response, yes they claim 4 degree timing advance. So if i am running a stock piston with the dynatek where should i be with the octane rating? I aggressive trail ride and do not have reasonable access to race gas it's a 45 min drive and i do not want to limit myself to that.
 

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Thank you for the response, yes they claim 4 degree timing advance. So if i am running a stock piston with the dynatek where should i be with the octane rating? I aggressive trail ride and do not have reasonable access to race gas it's a 45 min drive and i do not want to limit myself to that.
Regular pump gas is all you need. You only need higher octane gas if your running a high compression piston.
 
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With the extra spark advance could it start to knock on reg 87 octane? Never used an aftermarket cdi myself.

Sent from my SAMSUNG-SM-G870A using Tapatalk
 

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Thank you guys for the help, I will keep an ear for spark knock or pre ignition. Should have signed up on this forum years ago!
 

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Thank you for the response, yes they claim 4 degree timing advance. So if i am running a stock piston with the dynatek where should i be with the octane rating? I aggressive trail ride and do not have reasonable access to race gas it's a 45 min drive and i do not want to limit myself to that.

Not sure were you live, but Canadian tire, lordco, Napa, places like that all carry the additives needed to make race gas. You can mix it to what you need. Simple to use, cost about 15 bucks plus your fuel. You don't need it though. I use the Chevron 94, expensive but lots of bang for your buck. No other station has that octane, so they get my business for all my gas vehicles. Except my scooter, Yamaha doesn't recommend Techron in that one.
 

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Thank you for the response, yes they claim 4 degree timing advance. So if i am running a stock piston with the dynatek where should i be with the octane rating? I aggressive trail ride and do not have reasonable access to race gas it's a 45 min drive and i do not want to limit myself to that.
You may find the dynatek does not improve your performance with the stock piston. The grizz engine reaches the point of diminishing torque long before 6500 r.p.m.'s and never reaches the horse power output to get to the higher r.p.m.'s allowed for by the dynatek.
Plus, the stock valve springs will not keep up with the higher r.p.m.'s.
As for octane, I run 85 corn without a problem. The grizz engine is a low compression design, but try them all to see what works the best.
 
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Thank you guys for all the reply's I will try it out when i get my clutches back if i don't like it or i feel it is overrevving or valve float i will throw the stock one back in, fortunately it is easy to get to and swap out.
 

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You wont have the power to pull the higher RPM.No need to worry.
Ran one for years on my 660. Didn't notice any performance gains at all other than reverse limiters gone
 
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