The 2 the Max Project

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matt glascock
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Re: The 2 the Max Project

Post by matt glascock »

Agreed Maxie. What is interesting is that while we are discussing these principles in terms of the entire bike and rider moving along on a speed run, they apply equally, with certain adjustments in the variables, to all moving parts of the motorcycle. For example, within the motor, the resistance to optimal high-performance output (MAX power :-) ) is supplied by the friction at the interface of any moving part to anything else. The upshot being the need to address all these individual moving systems with the same attention to all the individual variables effecting ultimate speed performance as you do for the bike as a whole and to optimize the numerator factors and attenuate the denominator factors since your goal is to achieve ultimate velocity performance by the bike and pilot. This concept readies the table for discussions on enhancing internal engine, drive train, and wheel hub/axle lubrication, heat dissipation, and on and on and on. Good stuff!
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hodakamax
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Re: The 2 the Max Project

Post by hodakamax »

Thanks Matt, a good discussion for sure. I love this stuff. I'm not overly educated but I am a science geek and I do like to stir things up. I lost a very good friend last week and my memories of him will be drinking a wine or two and discussing the origins of the universe and other mind blowers like quantum physics. Not that we were qualified but interesting questions were asked and discussed. All good for the brain and we had a good time. There's more to life than TV we concurred. All strange but fascinating. It's been fun discussing practical applications such as how fast we can go with what we are limited to and Newton figuring this all out years ago to help us stay on track. Wow.

Max
taber hodaka
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Re: The 2 the Max Project

Post by taber hodaka »

wind resistance I think is a big factor, and wheel and tire size. I think Jack could have been a professor or maybe was at MIT. ----------------- Clarence
matt glascock
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Re: The 2 the Max Project

Post by matt glascock »

My condolences, Max. Hopefully the happy memories of times as you've described will replace the sorrow you currently know. Also, I agree - these are great discussions.
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hodakamax
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Re: The 2 the Max Project

Post by hodakamax »

Ok, back to reality and hardware developed to cheat the ever increasing wind force. These posture changing footpegs hopefully will allow the rider to be partially prone and reduce the frontal area of the rider. Sounds good in theory, whether I can fold up on this thing remains to be seen. Our recruited rider will have to be light and small but first things first.

Finally, one rear footpeg bracket has been fitted and the shifter linkage has been fabricated and assembled. There's still cosmetic work to do here but I must say that the mechanism really shifts smooth. It's time to mount the other side and figure out this proposed cable rear brake idea. One step at a time.

Maxie
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Hydraulic Jack
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Re: The 2 the Max Project

Post by Hydraulic Jack »

Matt,

What you are describing would fall under Newton's first law of motion. Objects at rest stay at rest until acted on by external force; objects in motion stay in steady motion until acted on be external force.

The external forces here would be largely drag. Seals, bearings, gear faces, tires, all turning energy into heat, which is a parasitic by-product constituting force applied against the object in motion. If you want to hunt for small fractions of parasitic drag, you can do such things as leaving out wheel bearing seals, and using extremely light weight grease, or even light oil, on the bearings. Not what you would do with a motocross bike, but for a one run, two run speed attempt, why not. It's just a maintenance hassle but can reduce rolling resistance.

Tires should have little or no tread. Flexing tread causes tires to produce heat, which is an energy loss. Tires should have very high pressure to limit flexure. It makes them tedious to ride, but reduces drag. You will notice that your average racing bicycle has ridiculously skinny tires with extremely high internal pressure. There is a reason for this.

Frontal area should be reduced where possible, and contoured where the area can't be further reduced. Spoke wheels generate a huge amount of drag. It's like turning two large, inefficient fans beating at the air, creating turbulance.

Even a small amount of fairing in the area above the front tire and in front of the rider can make a large difference in reducing drag, as can a fairing behind the rider which returns air flow to the slip stream with a minimum of turbulence. Consider the tear-drop shape. This is a very efficient aerodynamic shape, blunt end to the front, slender end to the rear. Even kids on bikes these days have helmets shaped this way even though they don't go anywhere near fast enough to make use of the shape.

And so on. These areas of design will gain more in the end than will shaving off a few ounces, even though you do everything you can in all areas. But what you look for is return on investment. How much effort, how much return. Go for the big ticket items first, then work your way down to exotic metals.
Hydraulic Jack
racerclam
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Re: The 2 the Max Project

Post by racerclam »

I just noticed that your building for building top speed , cool! Here is a customer of mine that just set a world record in August this year for 50cc class with his Honda NS 50 . I did the porting and carb work. I'm kinda proud 8o) He definatly got the stream lining thing figured out. You can see pictures that are more clear on the testimonial page of my web site

Rich
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racerclam
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Re: The 2 the Max Project

Post by racerclam »

Oh and The Bike that Greg Watkins built went about 87mph , it kept sucking the carb bowl dry and would have to recover a few times during the run . So I built him a large bowl carb but he hasn't gone back out with it

Rich
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Bullfrog
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Re: The 2 the Max Project

Post by Bullfrog »

Rich,

I may be missing something, but it looks like rising fuel levels will "trap" an air bubble in each of the two added "wings" of the re-worked float bowl . . . and that would limit how much additional fuel will be available. Is there some feature which allows the air in the new "wings" to vent to the original float bowl area?

Was higher flow float valve not an option?

On a VERY closely related digression, one of my mentors at PABATCO once told me the story of how unlimited drag racers had all seemed to bump into an invisible "wall" on top speed. It seemed that no matter what they did, they couldn't seem to gain any more significant speed/acceleration until . . . someone simply installed larger diameter fuel delivery hoses from the fuel tank. The details are foggy . . . but it might have been Don Garlitts???? (and he might have won the national championship on that idea?)
Ed
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racerclam
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Re: The 2 the Max Project

Post by racerclam »

Ed there was drilled holes in the upper part of the walls that were not there yet in the pic , Good call though 8o) and the needle valve was drilled as large as possible .136" and the pet cocks also opened up. . Running 5 miles at wot makes one thirsty. Garlits was a wiz, in 1974 he set the world top fuel record at 5.73 seconds and 243mph. Slow for now days. It was cool the we had that car in our auto shop for us to check out and sit in , at So NV Votech. He also pioneered the rear engine dragster after blowing his foot off

Rich
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hodakamax
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Re: The 2 the Max Project

Post by hodakamax »

Here's the other side mounted up with a front brake plate with a cable boss all modified to fit the rear hub. This in-between linkage has me baffled for the moment and I'm accepting clever ideas, even hydraulic. A brake rod is also not out of the question with a pivot where the old foot brake lever was. :?

Maxie
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viclioce
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Re: The 2 the Max Project

Post by viclioce »

Just looking at it from this one photo, I would guess that if you can change the pedal attachment point so it’s back about an inch to inch and a half further, that you may be able to do it by offsetting the brake rod with two, 90 degree bends, as long as you reinforce the 90 degree bends with something to keep the brake rod from stretching back out. Just a 90 degree triangular piece welded in place, or even just some additional round stock welded in place to hold the 90 degree angle. Seems like that should do the job simply enough. What do you think, Max? :ugeek: Victor

1978 175SL
1976 03 Wombat
1975 99 Road Toad (2)
1973 96 Dirt Squirt (2)
1973 “Wombat Combat”
1973 Combat Wombat
1972 94 Wombat (2)
1972 Super Squirt
1971 92B+ Ace
1970 92B Ace 100B (2)
1968 92 Ace 100
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; D Victor
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hodakamax
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Re: The 2 the Max Project

Post by hodakamax »

Ah, thanks Victor. I think I'm starting to visualize how to tackle the problem. I have to look at things for a while. I think by moving the foot brake arm 180 degrees where it's pulling rather than pushing and installing a bell crank pivot near where the old brake pivot was, it will be a straight pull to the rear hub with a rod much like the stock set-up.

The vertical movement of the swing arm is what complicates the problem for a direct hook up. By moving the transfer point bell crank near the swing arm pivot as in the stock position should alleviate the problem methinks. :)

Max
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Bullfrog
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Re: The 2 the Max Project

Post by Bullfrog »

With the brake lever pivot point and the brake rod attach point being almost at the mid-point between the swing arm pivot and the rear axle . . . swing arm movement makes a brake rod pretty problematic. This may indeed be a situation where cable or hydraulic actuation is called for.

Your last post suggests that you are thinking about linkage from the brake lever actuation arm forward to near the swing arm pivot and then linkage from there back to the hub brake lever? Or did I misunderstand the paragraph? Seems like a lot of linkages - but if the various pivots and Heim joints are pretty "tight" (not much free play), then it may be as good as (or better than) a cable setup.

Ed
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Bill2001
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Re: The 2 the Max Project

Post by Bill2001 »

Looks good Max.
I thought that a cable-actuated rear brake was on the menu? As BF notes, the relationship betw the brake rod and the swingarm pivot is critical.
At any rate, the use of bellcranks and tight pull rods is a good setup. Large-scale R/C aircraft use heavy, snug components so you may be able to swipe ideas or hardware from there.
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on a '72 Wombat 94

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MWL
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Re: The 2 the Max Project

Post by MWL »

You may have already covered this but I guess you're not planning on kick starting with the rear set in the way? Maybe one of those roller starters or just bump starting?
An easy solution for the rear brake would be to use the cable set-up and run up to an extra lever on the clutch side. Could be a shorty type lever below the clutch lever. Most of your stopping power will be from the front brake anyway.
Mike
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Re: The 2 the Max Project

Post by taber hodaka »

Are we shying away from a cable or did i miss something? -----Clarence
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hodakamax
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Re: The 2 the Max Project

Post by hodakamax »

Bullfrog wrote: Your last post suggests that you are thinking about linkage from the brake lever actuation arm forward to near the swing arm pivot and then linkage from there back to the hub brake lever? Or did I misunderstand the paragraph? Seems like a lot of linkages - but if the various pivots and Heim joints are pretty "tight" (not much free play), then it may be as good as (or better than) a cable setup.

Ed
Hey Ed. These ideas are are certainly flexible. A shaft and crank near the pivot point of the swing arm would only be a change of direction for the brake rod and only one step away from a direct connection. I'll try to fake it with a mock-up for our satisfaction. I kinda have to see things. :? The cable idea is still on the table as I've got a front brake plate mounted on the rear which is a start.

Maxie
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hodakamax
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Re: The 2 the Max Project

Post by hodakamax »

MWL wrote:You may have already covered this but I guess you're not planning on kick starting with the rear set in the way? Maybe one of those roller starters or just bump starting?

Mike
Hey Mike, Thanks for your comments. We haven't discussed the starting system at length yet. The kick start shaft, lever and gear will be non-present, I guess is the word. I haven't weighed the components but these parts probably represent nearly 1% of the total weight of the vehicle. Removing the starter gear from the crankcase adds a small but significant power gain from not having to spin the partially submerged gear in the transmission lubricant.

I'm getting too old for bump starts and envision a stand/starter mount to start the engine with some battery powered device which would be easier on the old guy. 8-)

Maxie
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hodakamax
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Re: The 2 the Max Project

Post by hodakamax »

Hey Bill, thanks for the tip on RC components, I'll explore that today!

Maxie
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hodakamax
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Re: The 2 the Max Project

Post by hodakamax »

Hey Ed and all. Here's a really quick and dirty mock-up of the pivot point I envision. I probably could have incorporated the original tube shaft if the DPO hadn't cut off the bracket. Pretty clunky looking now but could be precision made. :shock:

I'm still trying to envision the cable hook up which is still a possibility but the vision has not come to me yet. 8-)

Maxie
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Bullfrog
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Re: The 2 the Max Project

Post by Bullfrog »

It may be photo perspective . . . but is there any reason to be concerned about the toe end of the lever swinging down and contacting the actuating rod?

Yeah, while a cable seems easy on first thought, creating the "anchor" spots for the cable housing ends won't be easy. And there is the worry about rear brake cables which aren't nearly stout enough to do the job without housing "compression"/deformation.

Ed
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hodakamax
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Re: The 2 the Max Project

Post by hodakamax »

All clear here Ed. Now that I take a closer look, the Heim joint probably could be on the inside of the brake arm giving even more clearance.

Maxie
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Bullfrog
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Re: The 2 the Max Project

Post by Bullfrog »

Kewell!

. . . and it occurs to me that my concern about a truly stout rear brake cable housings is coming mostly from a dirt biker perspective . . . prolly not a big deal for speed record type of bike.

Ed
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hodakamax
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Re: The 2 the Max Project

Post by hodakamax »

To really be serious on the record attempt theme some other serious mods will have to be made. Don't forget the dual purpose road racer identity with its large heavy front brake and some corner turning tires which it will have first. The general design should lend itself to both purposes. Top speed can extensively tested in the road racer guise and should one want to try some record attempts other wheels could be fitted. Skinny aluminum rims and tires would be needed for less weight and rolling resistance along with less frontal area. Real gains would be noticed along with a reduction in billfold thickness. Just putting things in perspective as the project moves slowly along. :roll: Meanwhile one of the main objectives of entertaining me is being met as this is a really fun project without deadlines. Having it in the shop also gives me a feeling of well being at least in the motorcycle department. Just philosophizing here. :D

Maxie
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