Thanks for the tip with the valve springs. I´d never of thought that they would have that large an effect on performance (unless totally saggy)
My D shadow performes very much the same as Ducdude has explained, although i´m running 7.3:1, MK2s, 30mm Mk1 Concentrics and twin spark ignition (28° full advance).
100mph is max (this on the flat laid on the tank), although pick-up and low down torque seems acceptable. It comes onto the cam at around 2200, pulls well to 3800 and then seems to tail off dramatically (it will still accellerate up to 5000, but it takes so long in comparison, it feels like i´m punishing the beast).
I´ve learnt to use it well within this "power band" but am sure that more should come above 3800?
With ref to running in, i´ve read some interesting articles on running in cylinder/piston ring combinations where short hard runs with cool off periods in between seems to glean the best results (and make the most sense when you understand the mechanical theory behind this practice). Important to remember is that the bedding process causes only a minor removal of material from the rings/cylinder (high spots) whilst maintaining as much of the cross hatching as possible in the cylinder for the purpose of oil retention. To "soft" a run in will most likely cause glazing, increased friction/heat generation (causing expansion) and piston skirt to cylinder contact.
On the other hand, it sounds like Duc has new bearings, bushes, transmission, crank etc installed, and i´m pretty well convinced that the "slowly/slowly approach is going to achieve the best results here.
The best running in practice for the various mechanical assemblies seems to cause a bit of a dilemma with a complete new engine. (fast and hard for rubbing/sealing surfaces and low load conditions for bearings, shafts and bushes etc.)
On another note, i believe formula 1 engine clearances are so small, they are actually "siezed" in a cold condition. The engines cooling system is purged with hot coolant causing enough expansion to free off contacting parts before starting!!
My D shadow performes very much the same as Ducdude has explained, although i´m running 7.3:1, MK2s, 30mm Mk1 Concentrics and twin spark ignition (28° full advance).
100mph is max (this on the flat laid on the tank), although pick-up and low down torque seems acceptable. It comes onto the cam at around 2200, pulls well to 3800 and then seems to tail off dramatically (it will still accellerate up to 5000, but it takes so long in comparison, it feels like i´m punishing the beast).
I´ve learnt to use it well within this "power band" but am sure that more should come above 3800?
With ref to running in, i´ve read some interesting articles on running in cylinder/piston ring combinations where short hard runs with cool off periods in between seems to glean the best results (and make the most sense when you understand the mechanical theory behind this practice). Important to remember is that the bedding process causes only a minor removal of material from the rings/cylinder (high spots) whilst maintaining as much of the cross hatching as possible in the cylinder for the purpose of oil retention. To "soft" a run in will most likely cause glazing, increased friction/heat generation (causing expansion) and piston skirt to cylinder contact.
On the other hand, it sounds like Duc has new bearings, bushes, transmission, crank etc installed, and i´m pretty well convinced that the "slowly/slowly approach is going to achieve the best results here.
The best running in practice for the various mechanical assemblies seems to cause a bit of a dilemma with a complete new engine. (fast and hard for rubbing/sealing surfaces and low load conditions for bearings, shafts and bushes etc.)
On another note, i believe formula 1 engine clearances are so small, they are actually "siezed" in a cold condition. The engines cooling system is purged with hot coolant causing enough expansion to free off contacting parts before starting!!
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