Shimmed rocker shafts, roundfin Tonti

[guzzista]

This may have been covered before , but first time I noticed a Tonti round fin( LM1) with shimmed rocker shafts(no springs or bronze washers), something a PO  did a while back.  Any thoughts  other than on a street motor, ( which this is) does not make a whole lot of difference?

[Vasco DG]

The angle of the pushrods ensures that the springs and washers will work just fine. It's a system that was used for forty five years without issue. Why fix what isn't broken?

Pete

[guzzista]

That's what I thought. Back to stock she goes. Thanks Pete

[Vasco DG]

The way I read it was that the spring and washer had been removed and the end float removed by shimming? To me that seems un-necessary.

With a roundfin there is, (From memory, I haven't been inside one for a while!) only one washer and a spring as the steel rocker support precludes the need for a bronze washer on the thrust end. The squarefins with their aluminium carriers require two extra washers to help prevent galling.

Pete

[guzzista]

 Yes, the (bronze) washers and the springs had been packed away and some hardened steel shims were in place. In any case I put  the original bits back. I also found a 2mm steel spacer between the (correct type) rear drive and swingarm ( LM1) . Needless bodgery has taken place on this one...hopefully I wont find alloy gears in the timing case

[rodekyll]

The shim at the rear axle was to space a fat tire away from the swing arm.  I carry a 5mm shim in case I get a rubber-rubber during an on-the-road tire change.