Newsgroup: it.hobby.motociclismo.scooter
Titolo: Modifica forcella Burgman faidate! (lunghetto in inglese)

Girando per la rete disperatamente cercando lo scibile sulle modifiche
per la fiacca forcella dell'AnBurgher ho trovato questo:
Front Forks
Simon Evans writes
Ok so after 276 miles yesterday testing, here are the recommended
settings for the fork modifications. The soft springing has not proved
to be the problem I expected, and I put it down to the increased
spring effect supplied by the new viscosity of the fork oil and, more
significantly, some actual preloading of the spring. With more preload
and the far greater compression and rebound damping action in the
forks the light springs have not turned out to be too much of a
limiting factor. Good news really, as nobody does replacement fork
springs for Burgers - and no, they aren't progressive or rising rate
springs!
OK so assuming you REALLY, REALLY want to tune your bikes forks what
are the changes..? Well, the standard settings are as follows (these
are as measured on my bike alone and may not be representative of all
400 Burgers. I also haven't tried a 250 with the same mods but given
the lighter weight of the 250 I have little doubt that these settings
will be even more effective as the spring weight is less of an issue):
Fork oil weight and volume: 10weight 102mm air gap with forks
compressed
Fork Spring length and weight: 259mm, 1.2 Kg/mm 
100mm total spring deflection (measured on the spring rig, just before
coilbound)
Static sag (before modification) 35mm 
Full travel deflection for fork slider (i.e. Total available for wheel
travel, from bike on center stand and weight off forks to full
deflection): 110mm (suggesting that the last 10mm is absorbed by the
bump stops as the spring cannot deflect that far. So that explains the
`thumping` thenů)
Spacers in front forks length - standard 73.5mm 
Sag with rider sat - 65mm 
Phase One Modifications: Changed fork oil for 20weight Silkolene fork
oil, retained 102mm air gap (actually 275cc's per leg if you just want
to measure it out)
Fork spring length and weight - unmodified, apart from increasing the
preload spacer length to 79mm (used plastic plumbing pipe - a perfect
fit for 41mm forks, lighter than the aluminium standard spacer and an
old racers trick as it can easily be cut to length) ů and that's it.
Told you it wasn't rocket science! Total fork travel is now just past
90mm, but all of that is now usable (i.e. no banging down on the
stops). The static sag has been reduced by 40 percent to just 21mm
(that's the ride height of the bike on its wheels with half a tank of
fuel, but without rider, versus its ride height with all weight off
the wheels).
With 200lb me on board the sag is now just 41mm - it was 65mm before.
The importance of preloading the spring! This therefore means that in
total suspension travel terms, the `useful` travel has gone from
little more than 35mm (I'm not counting that 10mm of bone-jarring bump
stop) to about 48mm - an increase of 37 percent.
In the dynamic state the gains are even more obvious: Much smoother
fork control at town speeds, fewer `sharp` impacts coming up through
the seat or steering and much more steering stability at higher
speeds, with no trade-off in terms of handling `nervousness`. You can
also use far more front brake in confidence now that the thing isn't
plummeting down on the stops at the first sight of a brake pad! The
key result for me in speedhump strewn Surrey is the improved
performance over speed bumps - plenty of bump absorption with firmer
control - matched with greatly improved compliance over the rutted
goat tracks that pass for roads in this neck of the woods..!
Curiously, ultra-slow speed control is also improved - I've doubled
the `feet up` stationary time from 3 to 6 seconds - very flash at
traffic lights!
HOWEVER - to maintain the stability I had to increase rear preload to
around 12-10 clicks from maximum. Below that there is a hint of a
`wander` coming through the steering stem at about 40-50 mph and a
definite hint of a weave if cranked over at 70+... Now the cause for
this could simply be the worn tyres on my bike (6,116 miles at start
of test) or it could be a function of the increased precision of the
front end or the change in relative `set` of the front and rear -
we've already seen that raising the back end actually improves
stability on this machine so I think that's the most likely reason.
In any event, I am now much happier with the front end of my bike and
am happy to recommend it to anyone who can take the time and trouble
to get the forks off the bike in the first place. Just don't blame me
when the cursing starts!
Molder
Burgman400 - Zena

Ho deciso domani faccio la modifica, poi il road test e poi vi racconto. 
 
Molder
Burgman400 - Zena