Hello: i am about to take 2 frames to the welder both P11a, Can anyone supply me with a few photos detailing all the tabs which are usually cut-off when you find an old frame ex one has the front seat mounts cut "almost off" the both seem to be missing the tab for mounting the ignition switch . I am concerned about seat mounting stub/hook I have seen on a few pictures on-line this is shown at the front of the frame between the two lateral tubes. I can't find any decent drawings on the net there are many for commandos but not the 3/4 variants of P11. Any help would be appreciated a photo from the front looking down on the frame and one from the back and one from each side would be ideal.Then I will make the effort to do a drawing and put it out there on the net. tks. martin.
P11A frame details
- Thread starter canadel62
- Start date
Thanks for the pictures,... of course the trip to the welders prompted a few more questions:
1.0 Are the two lugs swaged into the frame for the gas tank mounting at the top of frame front available anywhere as parts or must they be fabricated.
2.0 Are the bottom engine mounting fixtures, two of them, basically a Tube between two triangular pieces of steel, on the frame available as parts anywhere or must they be fabricated.
both the lugs and one of the bottom frame mounts have been cut-off my "project" frame. thanks. martin.
1.0 Are the two lugs swaged into the frame for the gas tank mounting at the top of frame front available anywhere as parts or must they be fabricated.
2.0 Are the bottom engine mounting fixtures, two of them, basically a Tube between two triangular pieces of steel, on the frame available as parts anywhere or must they be fabricated.
both the lugs and one of the bottom frame mounts have been cut-off my "project" frame. thanks. martin.
grandpaul
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I wonder how similar/different my G15 frame is for the parts you mention?
For sure, none of the parts are available as sub-components.
I cut off the formerly raked headstock and obtained a replacement that I was thinking of welding back in place.
I'd sell the frame pretty cheap if you can use it.
For sure, none of the parts are available as sub-components.
I cut off the formerly raked headstock and obtained a replacement that I was thinking of welding back in place.
I'd sell the frame pretty cheap if you can use it.
Ron L
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I don't believe the cast lugs are available as separate pieces anywhere. The only other frame with similar pieces would be a Matchless G85. G15 frame is quite different and much heavier than P11. Also it is not made from Reynolds 531.
If you look closely at the construction of the P11 frame, the frame tubes are brazed into the cast lugs or the smaller down tubes are slipped inside the larger lower tubes and a cross tube "pins" the tubes together where they are brazed.
Also be aware that those pinched tube fuel tank mounts are pinned into the cast lug and brazed.
I have an early P11 frame where a previous owner tried to arc weld a side stand lug and blew apart the frame tube (Reynolds 531). To repair I need to find a donor frame that contains a good section of lower frame rail to above the left engine mount so I have enough straight tubing to insert a reinforcing tube before brazing. This frame also had the tank mounts cut off the neck casting, but those can be replaced.
If you look closely at the construction of the P11 frame, the frame tubes are brazed into the cast lugs or the smaller down tubes are slipped inside the larger lower tubes and a cross tube "pins" the tubes together where they are brazed.
Also be aware that those pinched tube fuel tank mounts are pinned into the cast lug and brazed.
I have an early P11 frame where a previous owner tried to arc weld a side stand lug and blew apart the frame tube (Reynolds 531). To repair I need to find a donor frame that contains a good section of lower frame rail to above the left engine mount so I have enough straight tubing to insert a reinforcing tube before brazing. This frame also had the tank mounts cut off the neck casting, but those can be replaced.
Thanks for the replies, if anyone would part with the lugs or engine plate mounts let me know, my guy said he would just fabricate them, he seems to be pretty good at this and works by day at a large comprehensive Machine shop with lots of tooling equipment etc. Let me know as I am in no rush , and the less he fabricates the fewer hours he will bill me for. Martin.
Welding R531 tubings will ruin the alloy. This particular alloy was developed specifically for brazing.
The alloy was developed initially for racing bicycles.
Selecting R531 fitted nicely into the manufacturing technology of the Plumstead Works, who brazed most of their frames right up to closure of the works (fabrication of the Commando frame was outsourced).
-Knut
The alloy was developed initially for racing bicycles.
Selecting R531 fitted nicely into the manufacturing technology of the Plumstead Works, who brazed most of their frames right up to closure of the works (fabrication of the Commando frame was outsourced).
-Knut
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pierodn said:
In English, the term "alloy" is often applied to aluminium/aluminum or other lightweight non-ferrous metal, however, that's not the actual meaning as many metals including steel, are 'alloys'.
'Alloy'
https://en.wikipedia.org/wiki/Alloy_steel
https://en.wikipedia.org/wiki/Reynolds_531
BillT said:
Not so. Assuming Piero meant G80CS, the main section (p/n 026070) was shared by the 500/600 AMC twins and the 350/500 roadster singles up to 1963 only. No G15/N15 at that point in time. For 1964, the roadster twins and singles, as well as the G15/N15 models, got a new main section (p/n 030090) to accomodate Roadholder forks, including a much sturdier headstock and a steering lock. The old frame main section was retained for the 1964--68 G80CS model because it was designed for the lighter Teledraulic fork which provided two-way damping as well.
It has been claimed that introduction of Roadholder forks on AMC models was an act of standardization. Not necessarily so. The likely answer is that increased weight, power and speed of the G15/N15 twins demanded a sturdier front end and front brakes (Teledraulic forks and 7in wheel hubs are a bit flimsy). Rather than developing an improved Teledraulic fork, AMC went the easy route and adopted the sturdier Roadholder fork and Norton's 8in hub, albeit with some changes to the former. In line with previous year's practice, all the heavyweight models received the same frame section and front end.
Regards,
Knut
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