Belts have come a long way in the last 20 years. The Gates polychain GT types, like you see on all modern Harleys, are functionally as stiff as chain and are, in the case of Harleys, rated for the life of the bike.
The GT2 profile on these belts are involute, so they are much quieter than the HTD profiles. The benefits of chain are diminishing with time, and at this point cost is the only advantage to people like us doing one offs. N. Christopher Perry > On Aug 10, 2015, at 9:46 AM, Peter Blodow <[email protected]> wrote: > > Ma first car, built in 1956, was a Fiat NSU 600, 600 cm³, 19 HP. It had > a 4 cyl. motor with a chain drive for the camshaft. I would never let me > down. Only thing was: to eliminate play, there were little weights > attached to every 4th chain link, forced outward by centrifugal force > and thus shortening the chain by excentric chain bolts. Once they were > pretty far out, they ground a channel into the alu casing and there went > my oil... took me too long to notice... > > Peter > > Am 10.08.2015 14:34, schrieb andy pugh: >> I recently replaced the cam-chain on my motorcycle. >> >> I am not sure I needed to, the new one I bought wasn't very much >> shorter than the old one. >> Examining the drive, it appears to be zero-backlash and to work with >> normal involute-toothed gears. >> In fact, it seems like an ideal drive for a CNC axis. It should be >> stiffer than a toothed belt, much stronger and (according to >> http://www.promsnab.info/catalogues/bosch/tooth%20chains/inverted%20tooth%20chains.pdf >> quieter too). They are also known as "silent chains" so there might be >> some truth in this. >> >> The requirements of a camtrain drive are very similar to those of a >> CNC axis, and it is interesting to note that the other main-player in >> camtrain drives is the toothed belt. >> >> An inverted tooth chain can run in oil. There are belt-in-oil camtrain >> drives on some engines, but I think that they are specially >> formulated. >> >> The cam-chain I removed had done 100,000 miles, most of it at 5000 rpm >> or more. (and up to 14,000 rpm) > > > --- > Diese E-Mail wurde von Avast Antivirus-Software auf Viren geprüft. > https://www.avast.com/antivirus > > > ------------------------------------------------------------------------------ > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
