Hey Flyman, did you get the P.M. with my number? If not let me know I will send it again. It would be way cool to talk bikes when you're in town.
First build, hopefully fast.
- Thread starter LandSpeedRecord
- Start date
Well the bottom end rebuild is done. It was extremely difficult to start a after putting it back together. With help from Cannonball2 here on the forum I figured out that the rotor magnet was installed upside down. Once that was correct it still would not start, so out of desperation I took it to the top of a parking garage and got it going about 20 and it started right up. I have a cylinder base gasket leak that I know the cause of. It's time to try some big gearing on this thing and see where the limit really is. Giving credit again to Cannonball for the idea I plan to add a Sturmey Archer 3 speed hub as a jackshaft. This I think is the best way to have the gearing for the speed I need for Bonneville and still be able to come away from a dead stop.
Heres a pic of the classic position. From 1954 I believe, notice the T shirt!! Im amazed he is wearing a helmet.
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Hey forget all the flattery and all the marvel over how the 66 will run. I'm guess you are working with that of the two or three engine sizes. First things first most if not all big shot builders are not going to mention that more likely than not the engines crankshaft rotation is too long creating unreasonable vibration. Well be it a few millimeters longer that it should be or not the stroke appears to be cause in my view. But at any rate if this piston is cut back to the second ring using that as a guide once the piston is lighter keeping in mind you must keep the exhaust port closed with a portion of the piston all that is remaining should be removed. That's it forget about the fancy port and polish for a minute and figure on cutting as much fat off the piston as possible and using the lower of the rings as a guild once cut remove the second ring. Hey there has got to be at least one person of the thousands of kits sold able to get one of the long stroke 48's to run near smooth for at least a few weeks of normal use. Any guessing ?,yeah I've not heard any complaints from anyone one the excess vibration and the causes of it but without correcting the stoke the alternatives few if you want the thing to turn on.
Boygofast, I took the weight off the piston side of the crank while balancing and it is now quite smooth from about 6000 to 10000 rpm. I get some harmonic vibration in lower revs that I can't explain but the rotating assembly is quite true and balanced now. I am still seeking pure horsepower for one of the two classes and I am hoping the pipe I am building will let some if not all of that power happen. I am far from a master builder but have experience and help in aero and general race bike building.
Cannonball, I got use of the computer we used to measure air resistance and have another friend running simulations on different positions. I am converting the rear axle to motorcycle style and could add pegs if the rules allow us to change foot position. It does say rear pegs must be removed I think but I need to 're read it and see if there is a loophole. The pedaling positions look strange in the motor world but they can be extremely aero when perfected. Think time trial bike maintaining 40+mph with .5 horsepower. Things change a lot doubling speed but for tucking and making the bike aero and upper body I want to keep as close as possible and maybe incorporate the lower from the pic?
If the rules don't allow rear pegs just add extensions to the axle and make a work stand for the bike to sit in, the extensions(pegs) are part of the stands assembly.
Cannonball, the rear pegs on the axle should work and be pretty easy to set up. For some reason I am worried about the cranks just free wheeling as we race down the salt. Any ideas on having the cranks lock in place once we are done pedaling?
I will say it again kid - BUY A RULE BOOK.
7.B.7
Footrests... and the rider shall use them for the entire run.
Only one set of rests is allowed.
.
7.B.7
Footrests... and the rider shall use them for the entire run.
Only one set of rests is allowed.
.
The AMA rule book is downloadable, I have it saved on the laptop but usually post from the phone and don't have it open to reference. There are several records set with rotating pedals, the most recent and likewise highest I have seen was the Sportsman Flyer guys with records above 73mph in the 175cc pushrod class. The records and rules often seem contradictory but there are at least 3 recent records that have been broken on bikes with operating pedals and one of them was bicycle based like mine in a special construction class also. The info is difficult to find but ite there.
This is not easy, I have done several forms of AMA sanctioned racing and I understand how to build and get thru tech inspection. This will be the most difficult I have ever attempted. I am chasing a life long dream to run there, not influenced by movies or media or any such thing, just my own passion for engineering and speed. I had no initial plans to break a record just to run and learn. The records in my classes are 93 and 94 mph and I think I have a good shot at one but not the other. I have begun a serious build, ground up for the next year to really go after special construction 100cc gas and fuel. For now I am going to see how fast a CG will go on a bicycle. It still has to get steering stops and a stabilizer and I'm converting to MC style axles. Anyway it's all still fun, happy motoring!
Sportsman Flyer's bikes had the pedals locked in place as pegs so they were
not used to propel his bikes because rotating pedals are not allowed in the classes he was in.
See no pedal chain and the crank arms are both locked pointing backwards.
This was the first 175 cc record bike.
Motorcycle rims and speed rated tires.
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I absolutely stand corrected. There are 3 records with crank arms not operating pedals. Actually simplifies some things I went over a bunch of times trying to figure out. That brings on plan C ha ha. Wet clutch here we come.
Just got the back up bike last night. Going to transfer this motor to it and start a ground up motor for this one basically duplicating it fresh. Then going over transmission options to get it off the line. My favorite is leaving the single speed manual clutch CG set up, adding a pull or drill starter and running the motor into a 3 speed Sturmey Archer fixed hub as a jackshaft. Another member on here did a great build with that hub and I think it's a brilliant idea for a transmission.
It appears that you are confusing SCTA records & rules with the BUB/FIA/AMA rules.
If you actually had read the BUB rules you would have already known you were only allowed 1 set of pegs. Chapter 2 2.C
Even under BUB rules, your bike will have to run in "A", and the engine class will be AG or AF - if you can convince them it is a "motorycle" engine. 66cc displacement put you in the 100cc class. Currently the BUB A-AG 100cc record is 92.422 mph.
That brings us to tires. If you intend to run in that class, you will need tires with a 112 mph DOT rating.
Nothing that has been done in SCTA BNI racing has any bearing on AMA / BUB racing or rules.
Talk to Pat Dolan (Sportsman flyer) He is a nice guy and will give you some good advice. I have some of his stuff, including a SF200 bike, and parts from him on a motorcycle I am building.
I had only meant to use the pedals with no additional pegs. That was scrapped a while ago to use fixed pegs on the seat stays. I thought the record was a touch over 93 in the fuel class and 94 in the gas class. Still hoping for August. Obviously tires are still the real problem. I had a friend who was an automotive tire engineer who put me in touch with Michelin engineer's. We went back and forth for three months to have them provide their E-Bike tires and state them capable of the speed and they just backed out. I am scrambling with two other brands to build tires but it could leave me where the others have been with motorcycle tires.