Canon VI-L - 1/30 and 1/15 running too long

[02Pilot]

Just picked up a VI-L that needs, well, a fair bit of work. Most of it is pretty straightforward, but I've got one issue I haven't encountered before. Speeds are good with the exception of 1/30 and 1/15, which are running much too long. I've cleaned the speed control mechanism and the slow speed escapement, and I'm not seeing anything obviously out of place. Anyone got any ideas what might be going on here? Thanks.

 

[nhchen]

I remember that on the canon cameras some of the speeds only work properly with the body shell on, could those speeds be the ones affected?
Nathan

 

[02Pilot]

Could very well be - I've only tested with the shell off thus far. I'll check it out. Thanks.

 

[02Pilot]

Yep, that's it. There's a secondary brake for the trailing curtain that acts on a linkage on the front plate that in turn works on the slow speed escapement. Thanks for the help.

 

[Peter Jennings]

7 series Canon's work that way as well. I was stumped by the same problem while cleaning a 7S recently.

 

[Ranchu]

You guys are awesome.