Power loss at 4000 rpm?

[tagordon]

Watching this for a while to see what resolved this loss of power.
Was the cause determined & I missed it.

Both my Airheads are pretty much dogs in fifth gear, unless wound up tight.
But in all other gears there is a rapid increase in rpm when 4000 rpm is reached, if I am at the same throttle.
I beleive that is when full advance of the ignition timing is reached.
Anyone else have the same happening?

[wiemer]

No, mine pulls from...ah-very low RPM's.
When not on the highways I make very low revs.
We in Holland are the people (of europe) the most fined for speed-doubtless for our own safety.
Really riding is not very funny here.

In Holland one cant judge a bike.
In France, with load, and hills, and twisty three-laners, max 110 kms, it is better to judge a bike.
But I have not had the occasion.(with this bike)

My advance stops at 3000, measured today (because I checked ign after Trolle's story- mine was also some degrees off.
Just one tiny wiggle of my beancan, just visible- on the flywheel 1/4 inch, I forgot how many degs that makes.

After that I had to turn down the idle speed, so I know there has changed something. 8-)



wiemer

[trolle]

Just to report some results:

After having done app. 1000 miles with the new electrical system, new digital ignition module, rebuild carbs and having synchronized the carbs and finetuned the ignition the consumption of gasoline has gone down with 10%, the engine starts without choker, runs very smoothly delivering power evenly from 1000 rpm and upwards to 7500 rpm and idles smoothly at 750 rpm when warm. I am a happy man  

greetings from a sunny and partly clouded north with excellent riding conditions

trolle

[nhmaf]

Trolle -

I don't think that it gets any better than that !!

Good job on your final "tweaks" - I need to check the ignition timing on my LS - though I think that it is at least close to properly
set (performance and fuel mileage is quite good) I am the sort who "just wants to know" if it is correct..

[mikethebike]

I had similar problems with an old BSA Royal Star twin which I fitted with a Boyer Brandsen set up.  It had to be set at high revs (Can't remember actual figure!) in order to check full advance was working. This was a three handed operation and I only have two!  You needed one hand on the throttle to hold revs steady, one hand to hold the strobe and the other (missing hand) to adjust the timing. This was further problematic in that the timing marks and adjustments were on opposite sides of the engine and the engine was revving its bits off whilst all this was going on!  I eventually found that I had been setting the timing too much retarded and that threw out the tickover and pulling at high revs.  The advance was built into the unit and the distributor centrifugal bob weights were no longer needed. (Another job to forget about!)  A call to the very helpful folks at Boyer and help from my son to do the third hand work did the trick.

[Semper Gumby]

My bike has a power loss when it goes over 7K.  I think there's something wrong on the seat.

I think that is where the valves start to float...end of cam and valve train...unless you put in trick springs, retainers and a cam with light pushrods.  Not to mention raising the compression and porting the head and going with bigger carbs.  (lions tigers and bears and oh my)...  

[Ed Miller]

My bike has a power loss when it goes over 7K.  I think there's something wrong on the seat.

I think that is where the valves start to float...end of cam and valve train...unless you put in trick springs, retainers and a cam with light pushrods.  Not to mention raising the compression and porting the head and going with bigger carbs.  (lions tigers and bears and oh my)...  

I forgot about this thread....  I was actually implying that I let off the gas.  I'm the thing wrong on the seat.  I do believe that it takes pretty much all of my R65's considerable horse power to push me, itself, and the big Windjammer through the air at over a hundred miles per hour.  When I ride my naked Triumph at those speeds, it feels like the wind is trying to pry me off the bike.  I try to hug the tank and tuck my legs in, but the kick lever on the right holds that leg away from the bike and my leg flops around helplessly.  That's even with both feet back on the passenger pegs.  Behind the Windjammer on the R65 everything is uneventful, unless there's enough cross wind to make the bike wiggle thanks to big saddle bags.

No I'm not in the Ton Up Club, but I do the try outs fairly often! Is the Reverend Horton Heat rockabilly?