Hi Piero,
Could you post a photo of your bike? There are several possibilities why your bike looks the way it does. It's anybody's guess. A previous owner may have fitted Mk2 and G12CSR parts due to a collision, or in an attempt to combat mudguards from cracking. I assume your frame number is genuin no e? The factory certainly didn't build 1965-67 M33CSR's like this.
If the front fender has the narrow type bridge, this points to a "homemade" conversion. There is a reason why the factory fitted two Y-stays for the Mk2 and M33 /export model rather than a U bridge with the big ribbed fender.
As far the rear fender goes, the short support tubes and grab handles 029440/41 was a poor decision by AMC for the G15 Mk2 and M33, which led to rapid fractures at the fixing points. You say the rear fender has the correct long chromed upper stays. However, the CSR came with a closed loop and a C-section alloy mudguard, equally susceptible to cracking.
The long chromed handles NM22634A together along with the chromed ribbed mudguard was standard fitment on the G12CSR. Thus, I believe a previous owner changed the rear mudguard along with the support tubes/grab handles of this bike into parts off the G12CSR, maybe off a wrecked bike. In my opinion, these look and work far better. It's a mystery why AMC offered these two bikes (the G12CSR and the G15CSR) with different cycle parts, but the ribbed steel fender theme seems to have been a mantra back then and it does provide far better lateral stiffness than a non-ribbed alloy fender. The non-chair version of the Mk2 (G15 Mk2 /home and /P) had black ribbed fenders front and rear, the front fender being identical with the G12 standard model.
029522 was a rear mudguard developed in 1962 for the 1963 model year to suit all roadsters including the G12 STD and the G15 Mk2 (either chromed or black). While it works well on the singles and maybe on the G12, it doesn't work well at all on the G15, as noted.
The G12CSR rear mudguard carries p/n 030194, which indicates it was designed in 1963 for the 1964 model year. It is less valenced than the previous one and I guess it was designed primarily to market the G12CSR as a sportster model against the 1964 BSA Lightening Rocket and the 1963/4 Triumph Bonneville rivals. (This goes along with an increased compression ratio). AMC were of course half-hearted in their attempt - they couldn't match BSA-Triumph's more modern unit construction engines introduced 1962 and 1963 respectively. AMC may have had an edge on chassis, forks and brakes though.
https://www.bike-urious.com/1965-matchless-g12-csr/
-Knut[/QUOT
Hi Knut.
If i look at pictures:
http://www.eurooldtimers.com/eng/galerie-stroj/3489-1965-ajs-33-csr-750-ccm.html
i can see that this bike is like mine: the front 33 mudguard has not the Y stays like my G15 but the simple bridge; same pictures showed the long chromed grab rear fender support.
What i have not understood?.
The only issue seems to me that my bike has the original 33 wear (like in the pictures) but has the engine stamped CSR.
The previous second owner said he bought it in the last of 70th and had never changed parts.
Thank you for letting me know better.
Piero