Newsgroup: it.sport.motociclismo
Titolo: De olia (lunghetto)

Memore dei problemi che non fan dormire il perugino RickyRD, quando ho
trovato il seguente messaggio nei miei archivi ho pensato di postarlo in
questa sede, giusto per intorbidire ancor di piu' le acque ...
----------------------------------------------------
     Thanks for the e-mail. I've had a look at the site and it seems the
     oil tests mentioned were done a long time ago (judging from the
     vehicles used and the reference to API-SG being the current car
     standard (it's now SJ)). However this doesn't mean the results are not
     valid today.
     There are several points to bear in mind about oils. First there was
     no motorcycle standard until very recently*, so manufacturers could
     claim anything they liked. A lot of hype goes into so-called "racing"
     oils and one way to make us believe we're getting something trick is
     to sell it at a very high price. Another way is to pay race teams to
     put the oil company's
     logo on the side of the bike. So price and endorsements are not good
     guides.
     Second, we get the same "bike-specific" arguments as those listed,
     especially shear-stable compounds that can live with bike gearboxes.
     Maybe this is hype, maybe there's some truth in it, maybe some
     companies have longer-lasting oil and others simply want you to think
     they have. One argument that sounds reasonable is this: all trick oils
     are expensive but trick oils designed for cars are a waste of money in
     bike engines because they do different things that bikes don't
     necessarily need*, so if you want to buy high-priced oil you may as
     well get a bike-specific oil on the off-chance it will have something
     your bike does need. But...
     Third, the Japanese manufacturers develop their bikes using basic
     quality oils (probably SF or SG, the type, from a reputable
     manufacturer, that's easily obtainable anywhere, at a reasonable
     price). It follows that for normal use, such oils are adequate - if
     you follow the recommendatiosn in the handbook and the oil/filter
     change intervals there shouldn't be a problem. Adding a better oil
     probably won't do any harm but it won't do any good either, unless it
     can extend the drain interval, but to find this out you need to use
     the oil and then measure its viscosity and have it analysed at regular
     intervals to determine just what the new drain interval is.
     *The reason the Japanese manufacturers instigated a bike-specific oil
     standard was that car oils were becoming too good! In particular they
     had anti-friction additives that were causing problems with the sprag
     clutches used in starter motors and the back-torque limiters built
     into some clutches.
     Hope this is of some help.
     John Robinson
-----------------------------------------------
(John Robinsons, gia' editore tecnico di Performance Bikes (l'unico "serio")
e autore della serie di libri Motorcycles Tuning, ha scritto il messaggio di
cui sopra dopo aver letto l'articolo di Motorcycle Consumer News gia'
postato da RickyRD qualche tempo fa.)
--
-- Luca.
--------------
VTR1000-FW
CBR600-FX
Cambridge, UK
ICQ 77956176

Consumer News gia' postato da RickyRD qualche tempo fa.)
In effetti questo messaggio, pieno di considerazioni giustissime, non
fa altro che confondere di piu' le idee.
Dubbi sull'attendibilita', o meglio sull'attualita', del test di MCN
ne avevo un po' anche io, in particolare a riguardo della moto usata,
vecchia e "paciosa". Del fatto che gli olii usati siano "vecchi"
(1994) non mi preoccuperei: il test serviva per verificare la tanto
millantata maggior resistenza degli olii motociclisti alle
sollecitazioni imposte dal cambio. Cosa che non si e' verificata. 
Al momento l'unico dubbio che mi rimane e' a proposito della
compatibilita' delle frizioni in bagno d'olio con olii SH e SJ. Il
discorso sugli innesti dei motorini d'avviamento, fatto notare da
Robinson, non mi preoocupa. Sul Dakota uso olio SJ ormai da parecchio
tempo e, nonostante la nota fragilita' dell'innesto borg-warner usato
su questo motore, non ho notato nessun problema (SGRAAAAAAAAAAT).
Anzi,  sembra che funzioni meglio del solito.
Ma perche' nessuna rivista specializzata italiana si prende la briga
di fare un bel test comparativo tra olii? 
Forse i petrolieri non vogliono!!! >:-)
Ciao
--
RickRD
MitoRD 350 (wow!) + Yamaha RD350 + Gilera Dakota 350 (*1.6)
+ Honda VTR 1000 F in ricostruzione!
Mantignana (PG)   
ric...@virgilio.it
"Amor est magis cognitivus quam cognitio" (Tommaso d'Aquino)

 Forse i petrolieri non vogliono!!! >:-)
... oppure per questo.
--
-- Luca.
--------------
VTR1000-FW Strada
CBR600-FX Streetstock
Cambridge, UK
ICQ 77956176

... oppure per questo.
Ho paura che questa sia la ragione principale! :-((
