In the Open Special Construction class no streamlining or devices to direct or redirect the air flow are allowed. Basically it`s just out there in the open. There is a Special Construction/Partial Streamlining class.
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New Last Build Thread "maybe"
- Thread starter halfmile
- Start date
Good stuff Phil.
I made a poster board template for the main center tube. Laid it out on the bike to visualize the fit and bent the center tube to match. A even 60 degree bend. I borrowed a 49mm hole saw and notched the front (steering neck) and 1 1/2" for the bottom cross tube. The best part of working with tubing is it`s impossible to make a mistake.
Everything always turns out right every time.
Well anyway the tube is bent and fits really good for a change. Tomorrow I`ll install the motor mount bungs and start tacking it together (running out of duct tape) so I can remove it from the jig and put it on it`s wheels to make sure everything lines up, mainly the rear wheel and chain. Haven`t decided on the rear upper frame tubes yet. Have to wait until the rear wheel is in the frame. With the center tube done it should go a little faster, besides 50+ degrees all next week.
Everything always turns out right every time. Well anyway the tube is bent and fits really good for a change. Tomorrow I`ll install the motor mount bungs and start tacking it together (running out of duct tape) so I can remove it from the jig and put it on it`s wheels to make sure everything lines up, mainly the rear wheel and chain. Haven`t decided on the rear upper frame tubes yet. Have to wait until the rear wheel is in the frame. With the center tube done it should go a little faster, besides 50+ degrees all next week.
Drilled all the holes for the motor mount bungs and cut some 188 wall tubing to length. Still have to drill the tubes out to 10mm. Need to find a laser cutter to make some steel mounts. Plan for tomorrow is to finish the front mounts and start on the rear frame uprights.
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Curious thought. holes dremeled in the fins or diagonally cut slots at a specific angle to direct airflow??? 
cra z?
cra z?
You need heat transfer for cooling. Too much velocity may cause a stagnant boundary layer. There was a cycle/cycle world article about oil break-down in the 80s. Then, the temp of 320f IIRC was OK, much higher caused viscosity break down. So an oil temp monitor would give a decent indication of how effective the cooling system is working.Curious thought. holes dremeled in the fins or diagonally cut slots at a specific angle to direct airflow???
cra z?
I got the rear uprights bent but I need to get another piece of 2" square tube (or grow 6 more arms) to make a fixture to hold the tubes the correct distance apart. They have to be parallel with the bottom rails for chain clearance then the tubes get bent (narrowed) towards the center main tube and coped to fit. For some reason I can`t seem to hold, measure, bend and notch the tubing at the same time.
My life long friend came by today and said it is no problem to write CAD programs for the motor mount plates. I`m really anxious to tack this all together, put the forks and wheels on it and set it on the ground to see if everything lines up so I can change my mind on most everything I see.
My life long friend came by today and said it is no problem to write CAD programs for the motor mount plates. I`m really anxious to tack this all together, put the forks and wheels on it and set it on the ground to see if everything lines up so I can change my mind on most everything I see.
What is the top speed you are aiming for?
What is the record speed in the class you are building this bike for?I haven`t even thought about that yet. I`ll be 77 yrs old when and if I get this project finished so we`ll have to see if I have "chicken feathers" where my competitive edge used to be.
You may need a "hot shoe" but don't ask me, I get scared at 70mph......we`ll have to see if I have "chicken feathers" where my competitive edge used to be.
Just finishing the bike will be a accomplishment. Making a run would be a cherry on top of the cake!
Seems very do able. I do not know the regs but a cam, tuning and a low profile should hit it.The record in the Open Special Construction 650cc Vintage Gas (AVG) is 134.422 mph. Seems awfully fast doesn`t it?
(Ignoring a real top speed of an XS650 at ~ 105 (or so). Another 30mph, a HUGE increase (Exponential Aerodynamic wise) . I might be available as parts runner, windshield wiper, general waxxer, washer and bratwurst griller when this happens...
What's the land speed record for a bratwurst grille?
@gggGary are you taking the Pi$$ out of The Brat GS1200 I love so much?
293 BPH (brats per hour).
