Just another nit, but it gets more complicated than that. Up thru 2012 BRP said the 998 RT's should be 1.0mm minimum. Then in 2013 they changed it to 0.5mm minimum.
Since this thread started with a question about 1330's, it gets more complicated. The spec for the 2014 and 2015 1330 RT's is as follows:
Quote:
The gap between the belt and the
sprocket internal flange should be
sum of "X" + "Y" = 3.25mm ± 2.75mm
(.13 in ± .11 in). If belt goes beyond
the outside edge of sprocket, have the
belt properly aligned by an authorized
Can-Am roadster dealer as soon as
possible.
NOTE: Belt can be in contact with
ONLY ONE flange from ONLY ONE
of the sprockets.
(Here BRP shows a diagram of the front sprocket which I wasn't able to paste successfully. It shows Gap "X" as the gap between the belt and the outer flange of the front sprocket. Below the diagram it is captioned as follows)
TYPICAL - FRONT SPROCKET
1. Front sprocket teeth
2. Belt
3. Sprocket internal flange
A. GAP "X"
(Here BRP shows a diagram of the rear sprocket. It shows Gap "Y" as the gap between the belt and the rear (inner) flange, i.e. the gap we're talking about in this thread. It is captioned as follows)
REAR SPROCKET
1. Rear sprocket teeth
2. Belt
3. Sprocket internal flange
A. GAP "Y"
End Quote
So what does this all mean? Well, if the front gap "X" were at its minimum, that is, zero, the rear gap "Y" could be at its maximum allowed per the equation:
3.25 + 2.75 = 6.0 mm. So that defines the maximum rear gap. 6.0mm. Assuming that does not put the belt outer edge past the sprocket outside edge which is not allowed.
To get the minimum allowed rear gap, we'd have to know the maximum front gap "X" that could occur if the belt were against the inner front flange. I don't know what that measurement is without pulling off the side panel and measuring the front sprocket versus belt width. However, since 3.25 - 2.75 is only 0.5mm, any gap "X" at the front greater than 0.5mm could result in the minimum rear gap allowed being zero or less than zero; logically speaking it would be zero. I'm sure there is enough width at the front that the outer gap "X" could be greater than 0.5mm (not having actually measured it). If we say the belt is touching the inner front flange, and since we're only allowed contact with one flange, then the logical minimum rear gap in this case would be "not touching" the inner rear flange. If we can get a 0.5mm gap "X" at the front and not be touching the inner front flange, then this spec tells us that the rear could be zero and would be allowed to touch the rear flange (one flange touching is allowed).
Why oh why did BRP make such a simple concept so complicated? Does it really make any difference compared to the old 1.0 or 0.5mm spec's? Only BRP knows...
Practical example: Right now my rear gap is about 3.5mm. Is that within spec?? From the rear of the bike and just eyeballing the front sprocket, I'd take a WAG that the front outer gap "X" is 1mm. The belt is not touching either front flange. So my rear gap "Y" must fall within the range:
Y = 3.25 - 1.0 +/- 2.75
Y = 2.25 +/- 2.75
Y = max of 5.0 and min of zero. Not touching either front flange, it would appear I would be allowed to touch the rear flange. I personally would not feel comfortable with that but that's just my gut preference.
In any event, since my measured gap of 3.5mm is in between 5.0 and zero, my belt placement is in spec. Now wasn't that simple?