I am Happy your results were positive but more power as a result of gear drive vs chain drive.? You must of had lots of chain lash or cam timing issues to feel a benefit of gear drive vs chain assuming cam profiles on each set of cams were the same. (maybe?) I would think a correctly set up chain system vs gear would deliver equal H.P.
Back at sturgis in 2000? i went to a dealer display, selling the gear drive over the chain style cams in the new harleys 1999 and on.
the booth was set up simple with a hand crank turning a mock-up engine (see thru type) one engine set was the stock chain drive and the other was the gear type...
Believe me Hoople the cranking difference was HUGE....
I could effort less ly turn the gears drives over , mind you BOTH were set up the same doing the same valve and spring operation.....
The chain drive was VERY hard to turn over and I mean hard.. I think they were using the term robbing "6/8 hp out of the engine".
I cranked on both back and forth trying to find a gimmick but found none.
I did go with the GEAR drives when i rode my bike back home... my crank never measured 0.001 out at the oil pump, (crank in block).. now that was good.
crank run-out wasn't as much a problem then on the older bikes... that was my first GOOD experience with gear drives in my 2000 hot rod.. The gears were quiet like they should be and I was happy.
but mind you, PLENTY more needs to be done to the older twin-cams than just the change out of the old shoe tensioners that have a problem.. ie; high volume oil pump is needed and better cam plate and or gear drive or chain drive with newer hydraulic conversion.
Hoople,
I hope you trust my opinion as I really did FEEL the needed power to crank the chain vs; the gear.......... LOTS
signed....BUBBIE