I know there are quite a few people out there with the new cdi so I'll get right to it. I was told be someone that was running 35 degrees of advance without the top end ignition retard, that he only picked up about 2-3MPH on top end on a Prairie 650 with intake/jetting/exhaust mods on 27" tires. What kind of MPH increases are you guys with the Dyna unit getting? I know not to expect to run 75MPH with only a timing change, but I would like to know some of your results, even if it is based on the indicated speed. The actual value may be off, but the difference should be close.

 

The machine's speed is limited by the clutch and engine RPM. The CDI will help it run up to it faster but not necessarily increase top speed. On some it may and others not. Tire sizes and accessories added weight factor in also. Dynatek spoke to me about the extended rev limiter and said a stock machine will never see it and possibly not the OE limit either. Clutch work, cams, intake and exhaust work will get you up there.
For what it is, the CDI is a great if not the best mod available. It releases the stock engines potential. I have one on the way.

 

Hey where do you ride localy?

 

I gained 4mph on top end with mine.

 

I am getting very inpatient waiting for UPS.

 

therock, Beasly ****, Davenport, Rock Creek, Windy Gap, Oakey Mtn, Anderson Creek and Rich Mtn (both closed for now), and less frequently Telico and Coal Creek.

 

Along with PRAIRIE633's question, I'd also like to add, what did your top rpm go up to, & how much of an improvement did you see in rpm, after the CDI's install... if any of you have a tach installed...

 

Well today I finally got the time to open her up! Topped out at 77mph on the speedo and 8780rpms on the tach!

It really halls some a$$ in a hurry, I still am alittle rich. I could have gone faster but I took it easy, I was worried about getting it jetted right! At about 60mph. it feels like at shot of nitrous the way it accelerates and pulls! Out of the hole it doesn't wheelie any more just spins the tires for 30ft. (on asphalt).

By the way, my terrible shake at 70 mph. has gone completely away thanks to my new set of MAXXIS Alltrac's! Those ATR's had great traction period. They leaked and were bad out of round!

I was able to open up and lean out my dial a jets all the way, so I had to order some more smaller jets today. My new setup with the 04 airbox, jethot exhaust and repacked silencer is running leaner than my last setup! I have noticed a greater increase in performance with my new setup though! My last had to much air intake with fatter jetting which didn't have the right air to fuel mixture. (I think?)

In my new testing I have noticed with a fatter main I can turn my airscrew in and out to lean or richen the main. Right know I have mine at 2 turns out and there is no annoying backfire after letting off the throttle either. Anyone else try the airscrew?

My fan did come on after I let some friends take it for a rip, but that was after 6 to 8 70mph.+ blasts. It ran for 30 seconds and shout off. That Evans coolant is GOOD STUFF!!

I have noticed after my runs the jethot is not so shinny close to the heads. That stuff is good for up to 1300* I think, I should be close to 1500* when properly tunned. I should have gone with the 2000* stuff, but thats not as nice looking? So I must be getting close! Jethot is a coating so you loose air flow volume but gain air flow velosity with hotter exhaust. I some cases you may have to lean down some! I think the Alien system for the v-force is like that?

If you could see the big smile on my face through the moniter right know![img]i/expressions/face-icon-small-happy.gif[/img]: I still have to try that modified clutch from Alltoys yet. That should be something!

Happy belated B-day to me!!!

 

wildwill, thanks for the info. Your Prairie has about every high speed trick I have heard of, CVT work, high compression big bore, cams, heads, etc. Your results will be a good benchmark for a stock Prairie 700 with the Dyna cdi only. I am really interested in what dominates the V-twins ability to get to, and past the stock rev limiter at 8500 RPM.

 

will, how do you come up with 1500* on your egt? (when properly tuned)?