ANOTHER Dyno Graph

[vfrman]

Ok, guys....I still have a dip at 5k. Standard airbox, K&N filter in stock housing, aftermarket needles (no idea which ones). Everything else is stock...don't ask me the size of my mains, because I can't remember.

Anyways, what do you all think of these graphs? I have a theory but wanted to bounce it off of the forum first.

On a positive note, after going down several sizes on the mains and 2 positions on the needle, the power climbed from 49 to 54 hp...






Here is a link to the old dyno graphs...and a pic of the needles. I am using the gold, thicker ones, but I have the thin ones as well.

https://www.flickr.com/photos/vfrman1/s ... 996305195/

[Cammo]

The dip in power and torque at 5k revs is not so bad in my opinion (some standard bikes are far worse), it's probably caused by being extremely rich in this rev range. Normally these revs would be associated with the needles.

Personally I think spending on known working needles (such as Risk O's road needles) is well worth it. I'm not sure what brand yours are, but Factory Pro brand for example are known to give very poor results.

The results are far better than the original graphs! How does it feel to ride?

[Ben_OB1]

Anyways, what do you all think of these graphs? I have a theory but wanted to bounce it off of the forum first.

Wouldn't be anything to do with the altitude of 1600m in Albequerque would it?

I live at sea level +8m, Adelaide Aus. When I had 110 main jets I took my NC35 to Australia's highest roads around Charlotte's Pass and The Alpine Way in the Snowy Mountains area, up to 1835m.

Above about 1500m elevation there was a very noticeable loss in performance and I had to gear down to maintain power delivery and speed
I am certain that I was running rich.

I now have 112 main jets and whilst the bike is running great around home I dread the next trip to the mountains!

A friend of mine did a motorcycle tour over the Himalayas, the highest road in the world, on an old Royal Enfield... they'd have to regularly stop and change jets as they climbed and descended the mountain!

I reckon if the bike is feeling good then 54horsies and only a small dip in torque is not too bad at all. Would be curious to know what mains you are running now.

Another thought, air correction contributes to the "emulsion" of the fuel to the needle jet. At lower atmospheric pressure you may need to open up the air correction to allow a little more (less dense air) and sustain the emulsion.

Ben.

[vfrman]

Well, I have only been able to ride it up and down the street for a sec after I changed over the mains and moved the needle clips. It is night and day. Before the bike would fall flat on its face at 5k coming out of a corner. Now it pulls right through without much trouble.

Check out that last graph...it is a/f vs time. The operator marked on the graph where he went from 3/4 throttle to WOT (like coming out of a corner). See how it goes from lean to rich at WOT? Also, the other graphs show the a/f going from lean-ish on the needles to rich on the mains, with mega-rich at the 5k transition. This makes me think I should go down one more size on the mains...

[vfrman]

I just checked my notes...I'm running 108f/112.5r on the mains. Maybe I should try 108/110...

[slo12]

Wish I had notes from the Shell bike. It pulled a clean 60hp at 4000ft + (Salt Lake). Drop the mains down.

[Cammo]

I just checked my notes...I'm running 108f/112.5r on the mains. Maybe I should try 108/110...

I would go further - try 105f / 108r.

[vfrman]

Wish I had notes from the Shell bike. It pulled a clean 60hp at 4000ft + (Salt Lake). Drop the mains down.

I wish you did too..