Dyno run

Got my slides back from Bruce at Triton, swapped the Boyer for a Pazon and ran it over to Twinline for a Dyno run this morning.



Good numbers - and interesting... 49.1 hp and 53.3 lb/ft at 5500 rpms. Twinline claims their dyno's off by about 3%, so 50 hp at the rear wheel = 60 hp at the crank. Torque curve was very flat. 37lb/ft at 3000 rpms.

Felt like a good clean pull, but fuel/air ratio plummeted from 2500 rpms, bottoming at 11:1 by 3500 then climbing back to a perfect 14:1 between 5000 and 6000. If I can iron out the jetting, I can probably eek out another couple of ponies.

Typical 4th gear roll on type run. Bike ran impressively there and back.

I need to scan the dyno sheets when I get to the office on Monday.

what you got in the motor dr

Motor's pretty similar to a Combat setup in carbs, comp ratio and cam. Some neat stuff in the engine, but that'd be easier for you to find in the archives than for me to re-write. Some photos of the build here: http://www.villagephotos.com/pubbrowse.asp?folder_id=1144453

The good news is that it was pulling strong all the way to 6k and will probably keep making power right up to 7k rpms. It also pulls really well down low.

Put the needle in the top groove. Hope it help with the over-rich condition (see the lower of the two sheets below - FAR falls of the face of the earth). It's the light blue line, and it corresponds with the dip in the dark blue HP line.

Neat

Is that a brake type dyno or an inertia type?

Jean

"You're spinning a 350 pound drum at 100 mph" was what Ian said. Would that make it inertial? I'll ask him on Monday.