Last summer, I conducted several individual timed runs on my 03 P650 at 100' and 300' to test the performance gains of various mods including the DG holeshot, P700 belt, P700 primary spring and EPI black secondary spring. I had so much fun that I thought I should do some more timed tests.

This time I did a combination of mods all at once and timed my P650 before and after. The mods that I tested this time included Dial-a-Jets, Nyroc Muffler Mod (drilled four 1/2 inch holes), Napa hose air snorkel and Twin Air filter. I spent a total of $220 on these mods (I did the installation work myself), so these are relatively cheap mods.

SEAT OF THE PANTS IMPRESSIONS
My seat of the pants impression of these mods is that it pulls wheelies from a dead stop a little easier than before and it has a little bit better throttle response, but overall its NOT A HUGE DIFFERENCE in how much faster it feels. The louder pipe gave me the impression that the engine is revving a little faster than it used to rev at the same speeds, but I don't have a tach to verify this.

TIMED TESTS
Now for the good stuff! Below are the avg recorded times of at least 3 runs for each measured distance plus a top speed run at approx 1/3 or 1/2 mile. All tests were conducted in 2wd in high range (unless otherwise stated) while riding on a dry, level asphalt road. Elevation was approx 95 feet above sea level and temps ranged from 48 to 60 degrees for all testing below.

BEFORE MODS
100' ...................3.12 sec
300' ...................6.30 sec
top-speed...........62 mph
(top-speed for low range....44mph)


AFTER MODS
100' ...................3.07 sec
300' ...................6.21 sec
top-speed............62 mph
(top-speed for low range....44mph)

I did notice during AFTER MODS testing that its easier to pully big wheelies. In fact, I had to let off the gas and start over several times b/c I pulled a big wheelie off the start line...whereas I only had to do that once during the BEFORE MODS testing due to pulling a big wheelie off the start line.


***CONCLUSIONS***
From the above time differences, I would guestimate that I improved my 100' runs by 1/2 quad length and my 300' runs by 1 quad lenght. This is NOT A HUGE DIFFERENCE...But for only $220, I feel like I got my money's worth. I think the Nyroc muffler mod with only 4 1/2 inch holes sounds a little louder than I was expecting...If I had to do it over, I might have used 3/8" holes in my muffler to see if that made it sound a little quieter. Otherwise, I'm pretty happy with the mods.

FURTHER TESTING NEEDED
Its worth noting that the AFTER MODS timed runs stated above were recorded using the middle setting (setting #3) on the DAJs. The DAJs have 5 pre-set settings and I did timed runs for setting #1 (leanest), setting #2 and setting #3 (middle setting). Setting #3 netted the fasted times and those are the times I recorded above. However, I ran out of time and did not get a chance to test settings #4 and #5. I hope to do that soon (possibly tomorrow if the rain holds off) and I'll report back if I found an significant difference using these other settings. One interesting note is that setting #1 (leanest) resulted in a maximum top-speed run of only 61 mph after several attempts, whereas I was able to reach 62 mph at least twice for each settings #2 and #3. This tells me that the DAJs are working properly b/c the extra fuel is apparently helping it go 1 mph faster at top-speed. I did notice that settings #2 and #3 occasionally resulted in a back fire thru the muffler when I let off of WOT whereas I never had a back fire thru the muffler with setting #1.

FUTURE TESTING
For my next round of tests, I would like to measure the performance gains of the new Dyna CDI. Can't wait until they finally start selling them!

Happy trails...[img]i/expressions/face-icon-small-smile.gif[/img]

 

MIKEY... as always an excellent, relivant & professional report... Thanks...

 

Mike W.,
One interesting thing that I discovered during this round of testing was that low range beat high range in the 100' times. Before Mods testing showed the difference was about .05 secs and After Mods testing showed the difference was about .13 secs. Of course, high range beat low range at 300' b/c low range would top out at 44mph while high range kept going to about 50ish before hitting the 300' mark.

Happy trails...[img]i/expressions/face-icon-small-smile.gif[/img]

 

mikeyboyesq that was an excellent report. one question though. did you have your holeshot module on or off? i did the #7335,nyroc muffler, 145f148r jets and .066 shim on the needles. but i lost my top end, it would go to 63 mph with me(280lbs) my son(130lbs) and a 50lb bag of dog food, but know i can only get up to 55mph in the same striaght away,long and flat. i have a feed market wright buy my riding area thats why i had the dog food, i was heading home. its a sport utility right. i was just using both the sport and the utility at the same time.

any ideas whould be greatly appr.

02 650p
#7335 hose
nyroc muffler
145f/148r
warn
snow plow

 

Thanks Mikey. that was the kind of information I was looking for in my post a couple of weeks ago. I will be looking forward to comparing my time and yours. Unfortunately, I did not time it before I redegreed the cams. I am going to have trouble finding a level road around here, though!

 

Deerchopper,
Good question...Yes I did have my DG holeshot turned on during the test runs.

As far as losing your top end, I recently read someone else's post that did some mods like the Napa hose and Dial-a-jets who also lost their top speed...I think he said he couldn't get over 40mph all the sudden. Anyway, I seem to recall that his problem was that he was too lean and he needed to go up a size on the main jets. I would hazard a guess that you also need to go up one size in your main jets. You can read your plugs to see if its lean...you know how right...run it at 3/4 throttle and hit the kill switch while still holding the throttle at 3/4. When you stop, let the motor cool and then check the color of the plugs...if white, you are too lean, if black, you are too rich...if light brown, you are perfect. Give that a try first and see what you find.

Happy trails...[img]i/expressions/face-icon-small-smile.gif[/img]

 

Customfab,
I look forward to seeing your timed runs...especially at 100' and 300' It will be interesting to see how your 100' compares to mine as I believe you said you lost a little umphh off the bottom end with the degreed cams...I'm also guessing you will more than make up for that in the 300' times. Too bad you didn't do timed runs before your mods...obviously, that would've been the best way to see the effects of your mods.

Happy trails...[img]i/expressions/face-icon-small-smile.gif[/img]

 

I did not do any timed runs but today I tested top speed level pavement at 61 mph. First run since installing web cams flywheel key and dial a jet was 58 mph, 27" mudlites killed top speed some came back[img]i/expressions/face-icon-small-cool.gif[/img] Nyroc exhaust mod next.

 

when you are doing a plug test do you have to be riding like you normally do or can you just rev it at about 3/4 throttle in neutral and do a plug test? thanks for your help.

 

Nope. It has to be wide open for about 30 seconds, under load, then shut off igintion, while holding throttle full open.