View Full Version : 05 1200c dyno sheet

10th August 2008, 03:30

I posted this in the wrong forum a couple days ago and couldn't get the pic to work so here we go agian. This is the sheet for my 05 1200c. It has Andrews N3 cams, a NRHS huricane flow A/C, and V&H shortshots. I am running a 45 pilot, and 190 main jet. It looks like I need to do some more playin with the idle side. But it runs real nice, so I hate to mess with it much.

10th August 2008, 03:56
Nice square motor. Looks like it is running fine.

10th August 2008, 04:01
Those N3's really make for a fun torque curve.

14th August 2008, 00:09
I would like to flatten out the A/F ratio at the bottom end. It seemed to run a litle lean with a 42 idle jet. So should I go back to the 42 and shim up the needle, or try the different taper needle? Anybody got any advice?

15th August 2008, 14:03
A dyno is run at WOT from beginning to end. That is, the slide is fully lifted, and the primary influence is the Main jet. Needle position and taper come into play mostly at partial throttle (when the slide is partly open). The idle/pilot jey has primary influense only at idle (slide closed).

It appears as though at lower RPM's, the A/F ratio is ok, then it gets rich at about 3,000? (no scale--guess) rpm before returning to normal ranges. Something either enhanced the fuel flow (unlikely), or the air flow was restricted in relation to the fuel.

The solution may not be carburation. Could be the cams, could be the exhaust. I would suggest changing back to stock cams and running the dyno again. The stock cams on the rubbermounts are very good, and hard to improve on for all around performance. Going to a "hotter" cam will typically degrade performance in the low to mid-range rpms, but improve it at the top end.

Are you sure that the tech had it at WOT the whole time? The bottom half of the run just looks a little odd for thiis model bike?

I just posted the dyno on my 2005 1200. Similar peak result (within 1 HP/ft-lb of torque), but the shape of the torque/power curves is very different. Unfortunatly, the dyno on my bike did not include the A/F ratio):frownthre.

Daytona Twin tec TC-88a Ignition
Dyno jet kit with slide
42 Pilot
165 Main
SE II slipons with Thunder Monster baffles.

I'm not an expert, just an interested amteur!

15th August 2008, 22:35
Swapping the old cams back and re-dyno isn't something I'm willing to do. As good as the stock cams are, there was a noticible boost with the N3's. Not at the top, but all thru the mid-range. The bike runs rich at idle now, if you let it idle and stand behind it the exhaust is gassy. But as I said, it seemed lean on the 42 jet, I'm going to go see if I've got a 44 in the shop an try that.

16th August 2008, 00:33
WHOA!! I guess this is why you should write stuff down. I've been jetting on both my bikes lately. Turns out I put the 42 in the 89. I had put a 50!! in the 05. I just backed it off to a 48, still smells gassy but it's gotta be better.