- Joined
- Jul 8, 2011
- Messages
- 2,668
Whitworth Ranch said:
The question was asked so I did a google search and now I know
The point is presumably "new carbs".Whitworth Ranch said:There's nothing strange going on with the dip. I turned the throttle too quickly on non-pumper/non-CV carbs with round slides, which just don't respond as well on rapid transitional throttle as other types of carburetors but do respond quite adequately with just a hair of restraint, as indicated below. The carb orifice got too large, too fast to provide signal to the jet, end of story.
Here was a clean run off the bottom. I didn't pick this one to post first because its peak wasn't as high, but is a quite normal run-to-run statistical variation in peak number. You'll note that the good bottom end was run 4, which immediately followed 3 with the dip, because I learned my lesson.
I still contend that the little stumble should not happen. I understand CV carbs, pumpers etc. but your stumble occured well after you whacked the throttle; the engine had already increased 400 rpm. Usually the whacked throttle syndrone occurs right from the start with a flat spot. Yours did not.
Furthermore, there is a significant difference between the 3rd (green) pull and 4th (red) pull at top end. Was the motor significantly warmer on the 4th pull conversely significantly colder on the 3rd pull? The 4th pull had a dramatic drop in power from 5,500 to 6,500 rpm when compared to the 3rd pull - any chance you feathered off the throttle on the 4th pull?
I've had Commandos that would pull clean from 2,000 rpm like a freight train with a quick throttle open and not missing a beat. Same bike in less ideal conditions and it would balk a bit.
