My first hot rod Norton

I should have said Cool, but I think I've already said that about Gene's project several times.

I'd like to apologize to all the dirty used black oil out there.

Could have been worse. I could have said Bitchin'
I think you’re supposed to call it ‘sick’.
 
One of my departed friends in Texas had a discription of "slick". "Slicker then cum on a gold tooth". He had no gold teeth so I don't know how he knew!
It has no color, but maybe a little off color. LOL I'm going to the basement and work on project!
 
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One of my departed friends in Texas had a discription of "slick". "Slicker then cum on a gold tooth". He had no gold teeth so I don't know how he knew!
It has no color, but maybe a little off color. LOL I'm going to the basement and work on project!
Texans have some pretty good ones. Almost never hear the same one twice.

How about "cooler than chrome dog shit on my dashboard"?
 
Ok got the rear frame extension fabricated. Using aluminum for the pan. Hope to get everything but the coil under the seat, that should be easy. As I said earlier the seat is exactly as I ordered, but after putting it on it didn't suit. So after cutting it apart the pics show what I ended up with, 2 inches shorter and an inch wider. The lines between the tank and the seat didn't flow the way I liked also. So I used a Slimline style, it's easier to cut off then to add on latter. Now we have all seen pretty glass matt when you have a mold to work with. Without a mold and you are hanging curtains it's not nearly as pretty, as a matter of fact it looks like shit! A couple additional layers and final trimming, I promise it will be fine.


My first hot rod NortonMy first hot rod NortonMy first hot rod NortonMy first hot rod NortonMy first hot rod Norton
 
Along with Ti studs to save weight I purchased a Lithium ion battery. The sales person was very knowledgeable and said this small one will do everything I need since it is not an electric start. that's 1 pound 8.8 oz. $90 plus $39 for charger. I have easily pissed more that that away.


My first hot rod Norton
 
Along with Ti studs to save weight I purchased a Lithium ion battery. The sales person was very knowledgeable and said this small one will do everything I need since it is not an electric start. that's 1 pound 8.8 oz. $90 plus $39 for charger. I have easily pissed more that that away.


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Good way to get some weight off your ride.

Plenty of doom and gloom out there about LiFePO, but you won't have any issues with the LiFePO battery with a minimal electrical system you make up. Don't short it though. It will melt quick.

My Antigravity battery is about the size of a fat wallet. It's been sitting for over a month in circuit while the motor is out of the bike and is still strong as ever. I put the charger on it because it was sitting so long and it went full green in 2 minutes. That's 14.5V.

Unsolicited thoughts: Use a reg/rec that supports LiFePO. I use a TriSpark MOSFET reg/rect and it is on the edge because it is not specifically designed for LiFePO, but on long rides it never gave me any over charge problems. I use it because it is small. Rick's Motorsport sells small foot print reg/rects that support LiFePO. Then of course there are the expensive ones that are huge. Your call choose wisely.
 
Been in one of those slumps. Trying to get frame ready for powder coat. Only got seat cut out and tail light mounted, needs some finishing touchesMy first hot rod Norton
 
I like that F-18 twin afterburner brake light. Bright and stylish. Should keep people off your rear end when you hit the brakes.

Your project is shaping up to be a one-off hot rod show piece. Impressive :cool:
 
thank you 50 feet or fifty mph. Taking a little break to finish up a ES2 that I have been gathering final parts for should only take a week
 
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Mick Hemmings believed that an alloy cradle flexed too much.

When looking at the cradle, and imagining the forces acting on that swinging arm pivot point when cornering etc. I concluded he might just be right.
Flexing occurs by lateral force acting at the rear wheel (spindle), not by differential vertical load. Resultant bending moment is taken up as a force couple in each cradle plate, so there will be no twisting of each plate, as one might think.
Transverse load acting at the (Commando) cradle S/A spindle support (via bushes) will indeed induce an out of plane bending deflection of the plates between spindle support and the isolastic support tube, and will also act as a tilting load on the engine.

Transverse load is acting on a very short length of plate, so I am tentative as to magnitude of the resulting deformation. No doubt any out-of-plane deflection here will magnify at the rear wheel!

Deflections of an alloy cradle can be reduced to a magnitude lower than a steel cradle by increasing the plate thickness over steel by a factor 3. Unfortunately, the weight advantage of an alloy cradle would be lost by this measure.

If wanting a very stiff (steel) cradle, the area between S/A spindle support and iso support tube should be closed by a web plate, forming a "beam" together with the two "flanges" (affected parts of cradle plates). Wall thickness of the web plate can be quite low, and I suggest keeping to the thickness of cradle plates. This mod will reduce cradle deformation significantly, and will reduce or eliminate tilting at the engine mountings.

Lateral displacement at the rear wheel will reduce but not be eliminated by this measure, the remaining lateral displacement being attributed to low stiffness of iso bearings.

- Knut
 
Flexing occurs by lateral force acting at the rear wheel (spindle), not by differential vertical load. Resultant bending moment is taken up as a force couple in each cradle plate, so there will be no twisting of each plate, as one might think.
Transverse load acting at the (Commando) cradle S/A spindle support (via bushes) will indeed induce an out of plane bending deflection of the plates between spindle support and the isolastic support tube, and will also act as a tilting load on the engine.

Transverse load is acting on a very short length of plate, so I am tentative as to magnitude of the resulting deformation. No doubt any out-of-plane deflection here will magnify at the rear wheel!

Deflections of an alloy cradle can be reduced to a magnitude lower than a steel cradle by increasing the plate thickness over steel by a factor 3. Unfortunately, the weight advantage of an alloy cradle would be lost by this measure.

If wanting a very stiff (steel) cradle, the area between S/A spindle support and iso support tube should be closed by a web plate, forming a "beam" together with the two "flanges" (affected parts of cradle plates). Wall thickness of the web plate can be quite low, and I suggest keeping to the thickness of cradle plates. This mod will reduce cradle deformation significantly, and will reduce or eliminate tilting at the engine mountings.

Lateral displacement at the rear wheel will reduce but not be eliminated by this measure, the remaining lateral displacement being attributed to low stiffness of iso bearings.

- Knut
Tusen Takk Knut - I assume you have an engineering
background … or is knowledge gained from eating gjetost ?
 
That Ti piece calculates at 70% of the steel bolt weight.
Strange, I've read that Ti is around 50% of steel weight. That's probably the internet getting it wrong again!
There are several sources that claim 50% however the Engineering toolbox lists it at about 60%.
Glen,
those two bolts measured by Gene are not identical (the Ti one being longer).
Matweb data tells us Ti grade 5 vs. bolt steel grade 10.9 have a density ratio of 0.568:1 .
Considering the need for nut(s) and washers(s) made of steel, the weight advantage of using Ti replacing a small number of rather small bolts is marginal.

- Knut
 
Quick ck on the swing arm before filling cut out for tire and then off to the powder coater!


View attachment 104358
Hi Gene, I noticed the final swinging arm has a rectangular transverse member (as per 850 Commando), while the one pictured above has a circular one. Did you work on two different swinging arms?
Also, could you please explain the advantage of the tie rod which acts like a rope or wire? Provided the tie rod is well anchored and the pillar mount doesn't collapse, it will provide a nonlinear stiffening effect for the tubes in the vertical plane, thus limiting bending in that plane.
However, given the location of schock absorbers close to the wheel spindle, bending of the (stock) swinging arm in the vertical plane is rather marginal.
In my opinion, stiffening the swinging arm against torsion and horizontal bending would be far more desirable.

Did you reinforce the swinging arm internally at the tie rod pillar? Thin tubes will benefit from a stiffening plate crossing the tube or encirceling it in the style of a collar.

Another issue is the detrimental affect of welding a heat treated swinging arm. You will have to monitor the S/A for development of cracks.

- Knut

Edit: Conservatively, a swinging arm can be considered a simple supported beam of length L and flexural rigidity E*I subjected to an end moment (M). The latter is the result of the vertical load P acting at the rear wheel axis times the distance shock mount (projected) to wheel spindle (L1).
M = P*L1 . Maximum deflection is of magnitude M*L^2 / (9*sqrt(3)*E*I) acting at L/sqrt(3) which is about 59% of L, counting from the S/A tube. (M) is low due to L1 being small, about 4" only. In modern monoshock bikes with a linkage, (L1) is usually much larger, hence (M) is much larger as well, resulting in the need for increased flexural rigidity.

For the reason explained, the tie-rod stiffening isn't really required. Lengthening a S/A is best accompanied by internal overlapping tube reinforcements.
 
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Same swingarm MTD-SON your a week to late. I used this swing arm design on a couple drag bikes, stiffened swing arm when I lengthened them 2 inches. I doubt this will make enough HP to flex this length swingarm, but some things just add to visual effect! The cradle suggestion sounds good but I just got the powder coating done, will be saved for the next hot rod project. If you weld on heat treated objects it is proper to run an annealing pass down the center then grind it off. DOD, Nuclear, Army armor X-ray qualified!
 
I like the crouching tiger hidden dragon Nija paint.

I applaud anyone that makes the classic Norton swing arm stronger. 👍
 
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