New project, need some opinions

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I have bits and pieces laying around and would like to make use of them.
First, I have an 850 motor that needs to be built. I also have a Megacycle 56000 cam and lifters in like new condition. I do not have any experience with this cam. Is this streetable? Does it have a good idle, approx 1200? I am mostly in the 4000 rpm range or lower. Is this cam impractical? I have no complaints with the original Norton cam. What is your experience?

2nd...Molnar products sells engine plates to fit a Commando engine in a slimline frame. I can either have the motor sitting vertical or sloped. The sloped version allows the Norton logo on the timing side to sit horizontal instead of vertical which, visually, is a big deal. I also see that it requires the use of the Commando primary cover. Try as I might I have not found any pictures of this arrangement. Can anyone out there locate photos and post them? Done it yourself? Pros and Cons?
 
If you are mostly in the 4k or lower rpm range, a stock cam would be your best option.
 
"fit a Commando engine in a slimline frame".
You might want to fit JS motorsport light weight pistons and con rods to reduce the vibration in a featherbed frame because vibration will be an issue.
 
Make your own engine plates not a hard job to do the plates for a Featherbed frame, sit the motor in the frame where you want it sitting and make cardboard templets, I made all mine for my 850 in the Wideline Featherbed, I used 5mm steel plates if you go alloy plates they need to be thicker, I can use the same plates for my Slimline frame if I go with a Commando motor but will have to change the front plates as the Slimeline has 4 mounting brackets on the lower front frame where the Wideline only has 2, just easy to make to suite.
The first 2 pics are my spare alloy plates but I now use steel plates as well make sure you have a very strong top plate from head to top of frame this is very important as well have your motor as far to the front of the frame as you can, mine has been set up this way since 1982 and have had no problems at all.
My crank has been balanced at 72% and is quite smooth and I run a 2S cam profile with flat top 40thu over size Hepilite pistons, head all ported and open exhaust system made for the Featherbed frame all tucked in so no scraping, didn't go overboard with my motor and is a great street rideable motor and has plenty of torque midrange.
Jim's light weight parts weren't around back in the early 80s when I built my Commando/Featherbed in fact no internet as well, I did 12 months planning in 79 when I brought my Featherbed frame off a mate.

Ashley
New project, need some opinions
New project, need some opinions
New project, need some opinions
New project, need some opinions
New project, need some opinions
New project, need some opinions
 
Yes that top plate up to the steering head is very important. I had lots of trouble on a slimline with a racing Dommie engine. Would literally tear the bolts out of the head.

Ended up taking the brace from the steering head back onto the frame. Like this. This is a new McIntosh Manx frame. My old slimline frame kept cracking down around the swinging arm.
 

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So the advantage with a vertical motor is I can retain my current plates and just make new front plates, the easiest of them to make.
also, I can use my current exhaust system with no modifications. That's two very good reasons. I still can't get around the tilted logo. is there any way to get the letters filled and the cover painted or powder coated. Has there been any powder coat compatible bondo developed?
Your motor is leaning forward..I assume it was necessary to remake the main plates to do that. Did the position of the transmission change?
 
I used a Commando head on the Atlas motor so I could get a three point bracket on the head for extra strength. I made my head steady bracket patterned after the original. So far, for regular riding there's been no problem. Then I made my own oil lines.
 
When I first set up my Commando motor in the Featherbed frame I used the old Commando rear plates you have to cut them up and I welded bits on to fit the Featherbed, I still have these rear plates hanging in my shed.
I used these for a few years before making new plates, I have my motor all set up if I need to work on my motor I can just remove the top engine mount and carbs and just undo bottom bolts the engine plates from the frame and I can lift my whole motor, GB, primary and all my bottom engine mounts all out at once and put up on the bench all within less than 30 minutes and even easier to drop back into the frame.
Also the bottom engine mount on the rear and the front engine where it bolts to the frame I have cube spacers that sit between the fame mount and engine plates where the bolts go through so when you tighten the mounts up you don't pull the frame lugs in.
A well fitting ridged motor to frame is all part of a Featherbed frame and handling.

Ashley
New project, need some opinions
 
Has anybody in this forum group tried the FeatherLastic frame mod ?
Running a rubber mounted motor in a Featherbed frame will upset the handling of the Featherbed frame as well the swinging arm can't be rubber mounted, mounting a ridgit motor is all part of a Featherbed design it becomes part of the frame.
I looked into the Featherlastic concept when they came around and you don't hear much about them these days so I say they failed, if you want a islastic Norton you stick to a Commando frame as well a Featherbed frame is a lot shorter than a Commando frame in the wheel base, but there are better ways to make a Featherbed run smooth with very little vibrations, I have done it and can ride mine all day, in fact it was an everyday rider till 2013 (I retired at the end of 2013) and most of its life was my only transport.
 
A sleeper , where it looks like ' an old Domi ' , isnt a bad idea . Stockish . With other bits , too .

However , if you MUST be awkward ;

New project, need some opinions


New project, need some opinions



and a tarted up old dog . https://www.oldbikemag.com.au/dunstall-norton-atlas-boomerang/

Met a straight who was selling the spare chain etc , 20 years later , to a atlas He'd riden down from Europe . 90 m.p.h. on the motorways , was its sweet spot .

HOWEVER , the angle of voitical , as regards PISTONS , if canted , aint . So as the resultant , being more inline with the frame down toobs , the action inem might be more ideal .
whatever , No paint in the joints , and no cheap tinny bolts , pulled up firmly , it might stay in . Plenty of room for a weber of DHLA in there , and a oil tank with enough oil .
 
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Running a rubber mounted motor in a Featherbed frame will upset the handling of the Featherbed frame as well the swinging arm can't be rubber mounted, mounting a ridgit motor is all part of a Featherbed design it becomes part of the frame.
I looked into the Featherlastic concept when they came around and you don't hear much about them these days so I say they failed, if you want a islastic Norton you stick to a Commando frame as well a Featherbed frame is a lot shorter than a Commando frame in the wheel base, but there are better ways to make a Featherbed run smooth with very little vibrations, I have done it and can ride mine all day, in fact it was an everyday rider till 2013 (I retired at the end of 2013) and most of its life was my only transport.
Do you have a picture of your bike from the left side?
 
Do you have a picture of your bike from the left side?
Here is a pic from the left side, been raining today so been up in the shed giving the old Norton a good clean and polish, been awhile this pic was take a few years ago from my phone, have gone back to my old Amals since.
Not the best pic but if you like more I will pull out the SLR camera and take better pics, pics taken from my phone lol, if you need any help at all I am only too happy to help, also under my tray under the seat I have now mounted a small bike 12v bike battery just so I can have a bright rear brake light, I share the battery with my Honda dirt bike, the round alloy oil tank I got from Lowbrows over your way, super light and fits so well, matches the round section of the frame.
IMG_20190414_173559[1523].jpg
 
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I want to use the lightweight JS pistons and get the motor balanced. He offers lightweight pistons for stock rods now. The balancing cost is about $300 including shipping.
If you’re going that far, IMO it’s worth going the extra mile and getting his rods. Here’s my recent thoughts…

 
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