Cobrafreak's board track racer project, has ended

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Re: Cobrafreak's board track racer project, never ends!

Yeah, on the right you have the flywheel, but it is farther forward in line with the crankshaft. Easy to avoid. On the left you have the Comet and if the crank arm was shorter you ankle would be next to the rear pulley shaft, and it moves fast. Putting a set of small rear sets would fix all the problems. The pedals will probably never be used, ever. They are just needed for the look and for moped legality reasons.
 
Re: Cobrafreak's board track racer project, never ends!

Thanks Cobra.... maybe ill just have to not pedal, and wear my steel caps just in case :)
 
Re: Cobrafreak's board track racer project, never ends!

Hi Cobra-

Just found this site and your project today- very nice work and your narrative of the progress is most interesting and helpful!

I have a survivor '15 Indian Twin and I might just have to fab up a bike like yours for everyday use...

Anyway, the comment I wanted to make was, you mentioned at one point that the steering was not stable. With your newfound performance and speed I imagine you'd want very predictable chassis dynamics. Due to my super slow dial-up net I haven't seen every pic, but it appears to me there isn't enough rake and trail for really stable steering. To get more rake you either need offset head bearings (I guess they are available for motorcycles) or reposition the head tube on the frame. You may not want to hear that but on the other hand you have shown willingness to get back in there and cut whatever is necessary!

One more thing: CA has a 150cc minimum for highway vehicles; since you are now over that, why not go whole hog and get a regular motorcycle registration on it so you can ride it anywhere with no restriction?
 
Re: Cobrafreak's board track racer project, never ends!

This bike is looking TOO RADICAL. That new engine is an inspiration... The whole bike is an inspiration, to be fair.
I've been helping a friend tear down an old 70's Super Bronc mini bike, runs a very similar belt transmission.
Very Cool.

Frank Lee said:
To get more rake you either need offset head bearings (I guess they are available for motorcycles) or reposition the head tube on the frame. You may not want to hear that but on the other hand you have shown willingness to get back in there and cut whatever is necessary!
Just a comment here: off the top of my head, I know Cane Creek makes an adjustable offset headset ("AngleSet") for threadless stems, but I guess you probably went threaded here. Happy riding!
 
Re: Cobrafreak's board track racer project, never ends!

Actually the bike is very stable since I have a complete ridged front end. When I was using the spring link front end the bike was scary in the turns. The problem was in order for stability from this fork the links had to be very tight at the pivot points. If they were tight the pivoting action was not very much. As wear set in on these joints it became impossible to get a stable ride. You could not ever take your hands off of the handlebars. When I put the new faux leaf spring front fork all the handling problems went away. I can in fact take my hands off of the bars and turns are inspiring. Very stable. But it is a rough ride as the only suspension is the pneumatic tires. It's ok though. A lot nicer to operate than with the old fork. To tell you the truth, leaf spring forks scare me because if the leaf cracks you are going to crash and there is nothing you can do about it. You are going down. As I said on previous posts I am considering re-registering this as a scooter. I would need to add turn signals and a high/low beam, and be inspected pay more insurance and pay a yearly registration fee. I have to look for any loopholes in the above, but I personally have to weight what I have now vs. what I will gain with the switch. Right now I never need to pay registration fees, ever. Lifetime plate. This is the ultimate "sticking it to the man". It makes me all warm and fuzzy that I never need to pay CA registration vehicle fees, the most costly in the Country. My Insurance right now is about $160 a year. Pretty low. I do have to stay on the edge of the far right or bicycle lane, but when I'm around my community or the downtown grid I just ride in traffic anyway because their speed limit is 30 and I just blend right in. The 45 and 50 mph zones I stay in the bike lane. People usually speed too fast on these sections anyway. I basically get to go anywhere I want to right now. With the newfound speed and quickness of the new engine it is actually much safer to ride as I am as quick as cars off the line and cant get in the way. I don't really think I really want to ever go on a freeway or highway because of my tires and brakes. They are fine for what I do now. We will see.
 
Re: Cobrafreak's board track racer project, never ends!

Frank Lee said:
Hi Cobra-

Just found this site and your project today- very nice work and your narrative of the progress is most interesting and helpful!

I have a survivor '15 Indian Twin and I might just have to fab up a bike like yours for everyday use...

Anyway, the comment I wanted to make was, you mentioned at one point that the steering was not stable. With your newfound performance and speed I imagine you'd want very predictable chassis dynamics. Due to my super slow dial-up net I haven't seen every pic, but it appears to me there isn't enough rake and trail for really stable steering. To get more rake you either need offset head bearings (I guess they are available for motorcycles) or reposition the head tube on the frame. You may not want to hear that but on the other hand you have shown willingness to get back in there and cut whatever is necessary!

One more thing: CA has a 150cc minimum for highway vehicles; since you are now over that, why not go whole hog and get a regular motorcycle registration on it so you can ride it anywhere with no restriction?

It would be easier for you to fab up a replica because you have the real deal and it would be much easier to reverse engineer by having a sitting pattern right in front of you. Please post some pictures. The ability to ride the real thing or replica every day is really something special. You would become famous overnight.
 
Re: Cobrafreak's board track racer project, never ends!

The '15 is apart at the moment so pics right now wouldn't be that impressive.

Thanks for relaying your experience with that springer fork. There must be some way of making it work though...

I totally understand the motivation to stay out of the "pay to play" class. I've been napkin engineering various moped schemes for quite some time now (and had been considering that HF engine too!) but due to geography it seems I need two vehicles: something for bopping around town, and something highway legal, and it seems there isn't an in-between. My town is quite small and rural so for now a regular bicycle and a Chinese electric bicycle are quite adequate for that, and a regular motorcycle takes care of out-of-town trips.
 
Re: Cobrafreak's board track racer project, never ends!

Just came across your build. Awesome build and lots of great info. Thanks for sharing. I'm in the middle of building up a bike and will go the same route to register my bike as a "MOPED" create a vin as you did and necessary safety stuff items to make it legit. Again thanks for sharing.
-Brian
 
Re: Cobrafreak's board track racer project, never ends!

Hey Cobra, Did you get a chance to ride your bike more over the weekend? If so how did it go? Dying to know......
 
Re: Cobrafreak's board track racer project, never ends!

cobrafreak said:
harry76 said:
Hey Cobra what is involved in registering yours as a moped? Do you need a headlight, blinkers, taillight etc? And what about the frame, wouldnt it need a VIN number or at least have to be approved by an engineer to get registered. At least that would be the case over here.... :x

You need a headlight and taillight. No blinkers are necessary. You do need to use hand signals. You need a horn and a mirror. That's it. You do the form online. They ask what the VIN is so you make a VIN plate. I used my initials with 1911 and a numerical sequence. I stamped a nice brass plate with the VIN number and affixed it to the frame. The DMV mails you your plate. I also had to get Moped Insurance through Progressive. It's just $160 a year. It was approved by an engineer, ME! :lol: I've watched Star Trek enough to know what Scotty would do in any situation.


So you used your first and last name initial and 1911, and stamped that on Brass? Like ex. Cobra Freak= CF1911?
 
Re: Cobrafreak's board track racer project, never ends!

Also on the DMV form under "MAKE" did you just write down the engine make?

Thanks again
-Brian
 
Re: Cobrafreak's board track racer project, never ends!

harry76 said:
Hey Cobra, Did you get a chance to ride your bike more over the weekend? If so how did it go? Dying to know......
I rode about 130 miles all over town. I wore my old time clothes and started in Old Sacramento. They have living history there with horse drawn wagons, black smiths, rail road conductors, you get the idea. I must have posed for a dozen pictures and a few videos. Lots of good conversations with people. It was a lot of fun. I went to Old Folsom and did the same thing. The bike is super reliable. I operated it for 8 hours. I changed the oil and half a quart came out. I put one quart in. I noticed a little oil is coming out of the breather tube at the valve cover. Just a drop at a time. This is probably normal. I should probably check the oil level every 50 miles to top it up. The oil was not dark but you could tell it was mixed with Chinese assembly lube and no namo oil. Change the oil early the first time. It was 80 degrees and no heat problems at all.
 
Re: Cobrafreak's board track racer project, never ends!

Great to hear Cobra, you must be having a blast. And now you get to enjoy the fruit of your labours.
Youll have to post some pics with you in your vintage clothes on the Indian in its current setup....

If it was 80 degrees and no heating problems do you think it would be worth testing my motor with standard flywheel and plastic veins removed or would the motor definitely overheat?
 
Re: Cobrafreak's board track racer project, never ends!

You mentioned you had a laser temp guage (if thats what they are called), did you get a reading off your motor? And if so do you know what the upper temperature range for these motors are?
 
Re: Cobrafreak's board track racer project, never ends!

One more question i have reguarding the CVT.... How did you go with lining up the chain sprocket on the CVT? Is it adjustable to line up with the rear wheel sprocket? Or do you need to position the motor to suit? And if so did your motor line up central to the frame?
 
Re: Cobrafreak's board track racer project, never ends!

harry76 said:
You mentioned you had a laser temp guage (if thats what they are called), did you get a reading off your motor? And if so do you know what the upper temperature range for these motors are?

I hadn't even bothered as the engine was not even in the realm of overheating. And I was putting around for about 2 hours at a slow 8mph. You can tell if it is overheating by not running well, detonating, and the sound the engine is making. I'll do a temp reading in the future, but it is well within safe limits. If I didn't have the fan on it may be a different story.
 
Re: Cobrafreak's board track racer project, never ends!

harry76 said:
One more question i have reguarding the CVT.... How did you go with lining up the chain sprocket on the CVT? Is it adjustable to line up with the rear wheel sprocket? Or do you need to position the motor to suit? And if so did your motor line up central to the frame?


You need to position the engine to suit. You can angle the chain sprocket to sprocket too, which is what I did. I wanted to get the engine as center mass as I could get away with and in order to do that I had to angle the engine about 1 to 2 degrees and then angle the rear wheel 1 to 2 degrees so the chain lines up perfectly. You can hardly tell and the bike still goes in a strait line. The majority of the engine case is off to the right side, but with the Comet on it is balanced on both sides. The valve cover is about 2 to 2 1/4 inches off center. No big deal. To angle the engine I just put a thick washer under the right two mounting bolts to the engine plate. The only way I could have completely centered the engine in the frame perfectly is if I had the left crank arm out farther that the right and for me to run a jackshaft to move the final drive chain over two inches. Too much work just for two inches. Any more and I would have run a jackshaft. Buy a go kart engine mount plate as it will be a lot easier to work with.
 
Re: Cobrafreak's board track racer project, never ends!

Thanks again Cobrafreak. Also did you have to take the CHP motorcycle course or did u just go to the DMV and take an eye exam and basic traffic law and sign test for a M2 license, and fill out the DL 44 form?
 
Re: Cobrafreak's board track racer project, never ends!

Thanks Cobra, your help is much appreciated. Thank you.

You mentioned buying a Go cart base plate? How would this help?
 
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