New 750 Land Speed motor Herb Becker is building (with pics, for real this time)

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Herb is building a new 750 motor to run at Bonneville Speedweek this summer. This 750 will have the same bore as our 920 engine (81mm), with a 73mm stroke. Here are some pics.




Cylinders. Pistons from JS Motorsports, to Herb's design. Cylinders sleeved with LA Sleeve FL80 sleeves, bored to 81mm.


One piece crank, 73mm stroke, machined manually by Herb Becker.


Here you can see the ring lands have been moved down to accommodate the considerable valve pockets, shown below.

 
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Lifters have been extended to maintain stability during high lift.
 
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Using Jim Schmidt's JS Motorsport 480 lift "Stage 4" cam


44mm intake and 38mm exhaust valves.


"Big block" Chevy pushrods.
 
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The head. Ported to 37mm. Intake face modified to accommodate larger intake tract.







 
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Steel plate to help re-inforce the cases on the "drive side".




Cases bored to accept high lift cam


The whole "Kit". Can't wait to hit the Dyno and see what it does!
 

Fast Eddie

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Beautiful stuff, especially that crank !

Interesting that you’ve gone for the long rods even with that short stroke.

Should rev like a 2 stroke on amphetamines !!

What cam are you using?
 
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Beautiful stuff, especially that crank !

Interesting that you’ve gone for the long rods even with that short stroke.

Should rev like a 2 stroke on amphetamines !!

What cam are you using?
Jim Schmidt Stage 4, .480"
 

lcrken

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Very nice, as usual for Herb. Interestingly, we will be running an engine with similar design philosophy, but with 75 mm stroke and 79.5 mm bore, in the same class here on the West Coast. Actually, we plan to run both the gas and fuel classes at El Mirage, but probably only the fuel class at Bonneville. Should be a good year for landspeed Nortons.

Ken
 

lcrken

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SCTA Bonneville record for 750 MPG is decent 137 mph... 60 rear wheel HP should do it..
Might take a little more than 60. Back in 2001 the best we could do with 61 RWHP was 131 mph in perfect conditions at Bonneville. But Eldo's bike looks to have lower drag than ours, so 60 might be enough. In any case, I'm sure he'll have WAY more than that with this engine.

Ken
 
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Might take a little more than 60. Back in 2001 the best we could do with 61 RWHP was 131 mph in perfect conditions at Bonneville. But Eldo's bike looks to have lower drag than ours, so 60 might be enough. In any case, I'm sure he'll have WAY more than that with this engine.

Ken
Hard to make comparisons, my 650 Triumph MPG bike has run 133 mph on 1-1/2 mile pavement in Maine at 1800 foot air density with 55 RWHP on a Superflow dyno...There's more drag with the salt but a bit less wind resistance.. And you need to make the 65 HP at Bonneville air density..But you know every bike and every run id
sdifferent...
 
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Hard to make comparisons, my 650 Triumph MPG bike has run 133 mph on 1-1/2 mile pavement in Maine at 1800 foot air density with 55 RWHP on a Superflow dyno...There's more drag with the salt but a bit less wind resistance.. And you need to make the 65 HP at Bonneville air density..But you know every bike and every run id
sdifferent...
Yeah, we ran this set up in 920cc congiguration (95rwhp & without the front fender) at Loring and did a 146.7 in the 1 mile and 149.2 in 1.5 mile. We felt we were still accellerating. Did a 154.2 on the salt, at the 2 1/4 marker and at the 3 mile.
 
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Yeah, we ran this set up in 920cc congiguration (95rwhp & without the front fender) at Loring and did a 146.7 in the 1 mile and 149.2 in 1.5 mile. We felt we were still accellerating. Did a 154.2 on the salt, at the 2 1/4 marker and at the 3 mile.
Interesting ,with less power at Bonneville than Maine you run faster on the salt despite the softer surface because of the longer distance I assume ?
 
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