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Following on from the individual technical specs posts, here's some more camshaft details.

Here are the details of the "alternative" camshafts used by Honda on the Swiss and Austrian restricted RD04, RD07 and RD07a AFrica Twins. Also, for comparison, are the camshaft details of the Transalp and the NT650V (Deauville). By the way, all the figures are what Honda call "1 mm lift". Not sure whether that is of the camshaft or the valve (if indeed there is a difference) is not clear. I'll just have to strip an engine one day and find out.

There appear to be three different camshaft profiles used in the Africa Twin -

1) Part Nos 14110-MS8-000 (Front) and 14120-MS8-000 (Rear)

2) Part Nos 14110-MV1-000 (Front) and 14120-MV1-000 (Rear)

3) Part Nos 14110-KW0-000 (Front) and 14120-KW0-000 (Rear)

These will be referred to from here on in as the "MS8", "MV1" and "KW0" camshafts.

Now then, as to which bike has which camshafts fitted -

RD03 -

These all have the MS8 camshafts.

RD04 (XRV750L 1990, XRV750M 1991 and XRV750N 1992) -

All Swiss market bikes have the KW0 camshafts.

The XRV750M and N (1991 and 1992) Austrian market bikes have the MS8 camshafts. However, the 1990 Austrian bikes got the standard MV1 camshafts.

All other markets got the MV1 camshaft.

RD07 and RD07a (1993 to 2000)

All Swiss and Austrian market bikes got the KW0 camshafts.

All other markets got the MV1 camshaft.


Valve timing details for the different camshafts -

View attachment 22092

Key -

BTDC - Before Top Dead Centre
ABDC - After Bottom Dead Centre
BBDC - Before Bottom Dead Centre
ATDC - After Top Dead Centre.

As you can see the restricted KW0 camshafts are quite different to the standard camshafts. These camshafts are also fitted to the 1998, '99, '00, '01 series of VT750 Shadow cruisers and, surprisingly, the Japanese market 400cc Bros (NC25).

The fourth camshaft shown above (14110-MBL-G00 and 14120-MBL-G00) is used on the NT650V Deauville (RC47) from 2002 onwards. Earlier Deauvilles had camshafts 14110-MN8-000 and 14120-MN8-000 which appear to have the same timing as the later camshafts and which also appear in the Japanese market 650cc Bros (RC31).


Oh, and by the way, the MS8 camshaft is used in all the following models -

NT650 Hawk GT (RC31)
NTV600 Revere (PC22)
NTV650 (RC33)
XL650V (RD10/11)
XL600V (1991 to 1999)

XL600V (1987 to 1990) had a different camshaft again - Part Nos: 14110-MF5-840 (Front) and 14120-MF5-840 (Rear) but I've not found the timings for those yet. These camshafts are from the VT500C of the same period.




 

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The 1 mm lift Honda uses for the lift durations is at the valve. That means the cam duration is measured from when the valve lifts 1 mm off the seat until 1mm before it sets back down. That's supposed to take out ramp and lash variables to make cam comparisons easier. The problem is, not every manufacturer uses the same mark for duration specs.
 
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