Sir Eddy's Rocket

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Hortons Norton said:
Awesome looking!!!!! May be heading back to the salt this year, Are you still on track for this year??
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I am keeping my fingers crossed but with the crank just showing up we have still a lot to do to make it ready for August.
We are going to push hard until the June 15th deadline to signup and if all looks good I will register and continue on.
If the motor is assembled by June 15th we will be taking the bike to the salt!
 
We have also been able to make a jig to hold the swing arm in place so we could cut it down two inches so that we would be legal for the new rule that the overall length of the bike can't be over 10% longer than production.
Eric at Alt metals in Vancouver WA did an amazing job cutting and welding, note that the mono shock mount is gone to make room for the tire moving forward 2 inches, what a great job!
Don't stare too long our you will burn your eyes...

Sir Eddy's Rocket


Sir Eddy's Rocket
 
Ive looked at the staggered cranks advertised on the MAP site, and wondered how they are balanced for racing ? Does anyone know what factor is commonly used in a commando fitted with one ?
 
Son of Siredward said:
We are going to push hard until the June 15th deadline ....
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Thanks for taking the time to make these posts, this site and posts like this one really helps keep me going until I get back. That crankshaft is a thing of beauty for sure & the swing arm "aint bad either" :D
 
acotrel said:
Ive looked at the staggered cranks advertised on the MAP site, and wondered how they are balanced for racing ? Does anyone know what factor is commonly used in a commando fitted with one ?
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I am not sure about the MAP cranks. We balanced this one at @ 50.49%.
I made the mistake of not dropping it into the cases before I shipped it off to be balanced so I contact Ro-Dy Cranks and asked him how much meat was left on it. We were needing to take off a total 150 grams to get it to come into balance.
Should work out that we remove about .100 TH off the OD of all 3 counter weights and it will come right in.
I sent the old bolt up crank to Ernie so that he can make sure it will fall in when I get it back.
I should have slowed down a little but it looked so nice that I boxed it and shipped it...
 
If that crank is short stroke , intended for a 500cc motor, isn't it over all smaller in diameter at the bob weights ?
 
Yes it is, it was already cut down and has only 553 grams for the bob weight. You can see how much in the pics.
 
It is certainly a beautiful piece of work. I've looked at the MAP site , and I believe that there is a long wait for their products, and I cannot afford a new crank anyway, However I might win the local lottery. With a staggered crank like that I'd consider building my motor to deliver top end power. It would be a real weapon with a decent set of cams, revving to about 8,500 .
 
Loooking Goood . But I think you need a Biafran for a Pilot , or existing needs to go on diet / hunger strike . ! :p :lol:

With feet Hard against Frame Sides , you should be able to loose six inches of Fairing Width , whichll be worth 5 or 20 mph .
Young Williams predisposition was to loose Frontal Area , anything here is free horsepower .
Theres confusion as to width / volume . The 6:1 Ratio for low drag , is for Volume , subsonic .

Seeing were not after 200 Gallons , the drop tank shapes unnessesary . The Supersonic Drop Tank shape is probly more relevant .

Elbows in , or forearms Straight Back from bars , elbows tucked in ( seating possition ) so no unnessesary protrusions will help too.
Then theres the toes . This is what the Brittens little wings afore the feet are fore , :oops: , despite Cathcarts nonplussings .

Can I have a Ride . :D
 
Weight doesn't matter for land speed but you need to get as narrow as possible. Stay out of the wind. I know you've been dreaming of taking yoga classes and now is your chance!
 
Son of Siredward, nice project and that is a great picture of your dad. That is also a great looking crankshaft, I googled Greg Blagus at Ro-Dy Cranks and read a lot of good stuff about him and his business. Did he copy the dimensions off your built up crank or did you have to supply him with blue prints? MAP cranks are in the $1700 range is this similar to Ro-Dy give or take a bit...thanks, Mark
 
Had a look at the vid of Ernie balancing the crank. Looks like he attaches appropriate weights to the big ends then spins it up on the dynamic balancer ? The question is does he use similar balance factors re the reciprocating weight ? A balance factor of 50% seems to indicate he only balances one half of it. I can't get my head around what effect the staggered crank has. Does he simply balance for minimum vibration/bearing loads ?
 
50 % of the Vertically inclined Mass . :p ( piston & 1/2 the rod & er , ' things ' ).

If you balanced it 100 % , the fore & aft imbalnce would be complete , 100 % .

Fairly safe to call that crank a Masterpiece .

presumeably Ea Side is balanced & the Center is ' both ' , as in cumulative overlapping counterweights for the vertical half of the about right bit .

Wonder if he's running a Combat Head . ! :p :D
 
marksterrtt said:
Son of Siredward, nice project and that is a great picture of your dad. That is also a great looking crankshaft, I googled Greg Blagus at Ro-Dy Cranks and read a lot of good stuff about him and his business. Did he copy the dimensions off your built up crank or did you have to supply him with blue prints? MAP cranks are in the $1700 range is this similar to Ro-Dy give or take a bit...thanks, Mark
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My Dad had a bolt up crank that he had made and we were going to run this until we had plans to turn it over 9000 rpm. My dad was talked into making a billet crank after talking with others turning Norton's over 9000 rpm and crank failure happening. I have the bolt up crank available if you have a road racer or something that you are not planning on pushing over 9000 or to 10500 to 11000 rpm. Nice crank, you can see it in the pics.

Sir Eddy's Rocket
 
acotrel said:
Had a look at the vid of Ernie balancing the crank. Looks like he attaches appropriate weights to the big ends then spins it up on the dynamic balancer ? The question is does he use similar balance factors re the reciprocating weight ? A balance factor of 50% seems to indicate he only balances one half of it. I can't get my head around what effect the staggered crank has. Does he simply balance for minimum vibration/bearing loads ?
Click to expand...

We ended up sending it back to Greg at Rody Cranks and had him rework the crank after we found that it was too far out, my dad said to make it identical to the bolt up and not to worry about balancing it. He didn't take into consideration the large cutout in the stock center counter balance for the oil passage in the Norton Cranks have. Ernie balances the cranks for minimum vibration/bearing loads. He was known back in the 70's and 80's for balancing Harleys and lightening two strokes. Any one that was racing would send his cranks to him and he was the wonder man. He is a blast from the past from his place out in the woods to his mellow laid back demeanor. One of the people that you meet that you never forget. He is not in the phone book and works off the grid... I was able to go to Greg shop out in Detroit and have a beer, he sent the crank back to us balanced and ready to set in the cases so I never had to go back to Ernie to have him rebalance it. I would highly recommend Greg Blagus for any crank work, he knows what he is doing.
 
Matt Spencer said:
Loooking Goood . But I think you need a Biafran for a Pilot , or existing needs to go on diet / hunger strike . ! :p :lol:

With feet Hard against Frame Sides , you should be able to loose six inches of Fairing Width , whichll be worth 5 or 20 mph .
Young Williams predisposition was to loose Frontal Area , anything here is free horsepower .
Theres confusion as to width / volume . The 6:1 Ratio for low drag , is for Volume , subsonic .

Seeing were not after 200 Gallons , the drop tank shapes unnessesary . The Supersonic Drop Tank shape is probly more relevant .

Elbows in , or forearms Straight Back from bars , elbows tucked in ( seating possition ) so no unnessesary protrusions will help too.
Then theres the toes . This is what the Brittens little wings afore the feet are fore , :oops: , despite Cathcarts nonplussings .

Can I have a Ride . :D
Click to expand...

Hey Matt,
I am working on not being so thick... We are built a little wide but I will get behind the fairing.
 
Amazing to see that chunk of steel the crank came out of, looks liked 3 cranks worth in mass. It would be interesting to see the blank as it progressed thru the machining stages.

Thanks for info on the bolt up crank but I like the billet crank whether I would ever need the rpm potential or not, I'm not sure if one of Gregs cranks is in the budget but maybe someday for another project...Mark
 
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