Author Topic: 500cc pushrod bike project  (Read 56443 times)

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Offline 1212FBGS

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Re: 500cc pushrod bike project
« Reply #15 on: October 14, 2008, 02:21:39 PM »
hey Jim here is a link to cone eng they have really cheep megs and are off the shelf http://www.coneeng.com/pdf/cone%20list%20PDF.pdf

why dont you sell that h2r fairing on ebay and i'll sell ya a better one for what ya peddal the h2r fairing for

are you using some of the stock cx stearing head?

kent

Offline JimL

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Re: 500cc pushrod bike project
« Reply #16 on: October 14, 2008, 11:45:29 PM »
Hi Kent...the steering head/frame head is stock Suzuki GSX600.  I boxed it to my homemade frame.  Not sure about the fairing idea...this one is nice and wide to cover the goofy engine setup.

I'll drop your steering column and shaft parts tomorrow, if you are around.  I found a really trick 75 degree angle shaft coupler that rotates smooth as silk and fits the upper column and lower slider shaft...it might work really well where the driver is close to the front axle; it's an amazing part!!  I don't need it as my RMR will have traditional steering.

Jonny...the V6 on the bench is for my rear engine mod roadster project, currently hanging from the ceiling over the bike project!  It's an old bored/stroked Tacoma V6 with Hilborn system for E/Fuel (it's about 4.0 liter, and actually is an orphan from long ago USAC development).  It's a fuel only block, and can't be run on gasoline (no cooling below the upper bore area).  As usual, I'm trying to put the car together with old Toyota parts ('cause that's what I have).  I put another pic below.

and...as usual, I have NO idea what I'm doing....just creating weird theories and testing my wifes patience.   8-)

Regards, JimL

Offline tortoise

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Re: 500cc pushrod bike project
« Reply #17 on: October 15, 2008, 10:33:13 AM »
Where are the pistons coming from for the scooter? The unique twisted geometry would seem to require something expensively custom.

Offline JimL

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Re: 500cc pushrod bike project
« Reply #18 on: October 15, 2008, 09:21:30 PM »
My best guess is to keep the stock pistons, mill the heads a little, camshaft change, and spin as hard as it will.  I checked the budget....doesn't say anything in there about custom made, gold plated, diamond jewelled, one-off pistons!  :lol:

It's a "just for fun" project, so I'm enjoying myself.

Regards, JimL

Offline John Noonan

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Re: 500cc pushrod bike project
« Reply #19 on: October 15, 2008, 11:27:04 PM »
Jim,

If you need custom pistons let me know, I give a racer discount.

J

Offline JimL

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Re: 500cc pushrod bike project - another puzzle going on...
« Reply #20 on: October 17, 2008, 02:43:17 AM »
So here's the problem.  I slipped one of Airtechs fairings over the bike (pic below) and the Suzuki forks are wide enough that the handlbar position is right at 6" to end of bar, from centerline of the tube.  The rule book says hands 6" from fork tube, but doesn't say which part of hand.  Width is no problem (well over 10" between closest part of hands).

Is this a case where the fairing has to be cut and bubbled?  Kinda looks like it to me.

It is a pretty good fit for my (relatively) low bike.  1/2" lower and I wouldn't make the front rim height/streamlining fit requirement.

I also need to make a correction and comment, here, for those following along.  Regarding the jackshaft, I discovered that a CB500T or CB450 output shaft is a better fit than the input shaft.  It has a longer broached section for fitting the driven sprocket, and can be shortened to fit inside the fairing.  Also, it is 25mm all the way except the 20mm end.  By cutting off the 20mm end, both pillow blocks (25mm) can rest on the same plane (no tricky shimming necessary) and the overall fit is better.

I'm sure I'll learn more lessons as I go.  That one only cost about $65, which is probably cheap by hourly rate, but pretty tough when counted up in my favorite "chocolate chip cookies" and "senior coca cola" from McDees!!

Regards, JimL

Offline willieworld

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Re: 500cc pushrod bike project
« Reply #21 on: October 17, 2008, 08:56:07 AM »
the rule is the hands have to be outside the width of the fork tubes ----but it is suggested that the thumbs be 10 in apart ---the 6 in is  minimum between the hands not from the tube      read the rule again        willie buchta
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Offline Sumner

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Re: 500cc pushrod bike project - another puzzle going on...
« Reply #22 on: October 17, 2008, 10:32:50 AM »
...................I also need to make a correction and comment, here, for those following along.  Regarding the jackshaft, I discovered that a CB500T or CB450 output shaft is a better fit than the input shaft.  It has a longer broached section for fitting the driven sprocket, and can be shortened to fit inside the fairing.  Also, it is 25mm all the way except the 20mm end.  By cutting off the 20mm end, both pillow blocks (25mm) can rest on the same plane (no tricky shimming necessary) and the overall fit is better.......................................

Could you post a picture of the new jackshaft if or when you have it.  Nice build,

Sum

Offline JimL

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Re: 500cc pushrod bike project..thanks Willie
« Reply #23 on: October 18, 2008, 12:44:20 AM »
As those who know me, know...if I read something twice it'll have a completely different interpretation.  Thanks for the guidance.
Like my daddy used to say, "Time sure does fly when you're confused!" 

Ill post pics of the jackshaft setup when I get the new pillow blocks (hopefully doing the fit up next Monday night).   In all honesty, Monday nights are often the time I undo or redo what I did on Saturday.  I kid a lot, but this is actually how my projects seem to go. 
The "Saturdays and Monday nights" has been a decent method for me, for quite a while. 

On another note; I've been doing a little studying about "torque induced gyroscopic precession".  After a lifetime of riding 2-wheels, this is the first I ever new what keeps the things from falling over.  It also explains what radical geometry combined with enough wheel/tire mass can do to generate "speed wobble" after change in torque input (a bump, a steering input, or sudden increased power application to the driven wheel).  From what I've learned so far, gentlemen, SHIFT/POWER UP GENTLY when the speeds are high! 

It also explains the wiggle that often occurs on drag bikes, late in the run when tires and shifting hook up together.  In fact, the light bulb went "on" (reading the articles) about a vicious wobble my Buell M2 threw at me, one day, on the 91 freeway.  It was a full throttle 4-5 upshift, and the shaking and wobbling was unforgettable!  I hadn't experienced that since my days riding flat-trackers on the 1/2 miles.

I'm suspecting this is an ugly deal if the bike has to be leaned while running in a straight line (weight balance off)....any hard shift, at speed, will create torque induced gyroscopic precession because the rotating wheels are not at right angles to gravitational pull (precession will try to turn the front wheel into the lean angle). 

If you think it can't have that much force, try the simple "ten-speed bike wheel, spun by hand, trick" (described by physics instructor) for a real shock....don't hurt yourself.

Maybe everyone knew but me, but the good articles I've found on physics websites have really opened my eyes.  I need to pay attention to the side-to-side balance (anybody old enough to remember Vespa wobbles?)

Have a great weekend, folks!
JimL

Offline JimL

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Re: 500cc pushrod bike project - megaphones fabbed and footpeg mounted.
« Reply #24 on: October 19, 2008, 12:10:17 AM »
Just one quick pic.  I had to build the megs, before I could figure out where the right footpeg lives.

JimL

Offline willieworld

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Re: 500cc pushrod bike project
« Reply #25 on: October 19, 2008, 12:48:09 AM »
jim  looks good  keep the pics coming    willie buchta
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Offline generatorshovel

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Re: 500cc pushrod bike project
« Reply #26 on: October 19, 2008, 06:48:31 AM »
Jim, I'm following your build closely from OZ , it great to see someone thinking outside the square , well done mate.
Tiny
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I would prefer to make horsepower, rather than buy, or hya it, regardless of the difficulties involved , as it would then be MINE

Offline 1212FBGS

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Re: 500cc pushrod bike project
« Reply #27 on: October 19, 2008, 11:09:32 AM »
hey jim
I have be inquiring about the spinning mass and will probably put a juicer on the gyro... i need order a bunch of megs from cone next week for those 4 Motobi's i need to build, give me a size and i'll order ya a couple.... i also have a set of handle bars for ya...
kent

Offline sockjohn

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Re: 500cc pushrod bike project - megaphones fabbed and footpeg mounted.
« Reply #28 on: October 19, 2008, 11:45:59 AM »
Just one quick pic.  I had to build the megs, before I could figure out where the right footpeg lives.

JimL

I'm asking for my own knowledge, does the lower megaphone meet the 7.B.20 rule as being pointed away from the course surface?

I've always assumed it could point straight back, but not downwards, but how much angle down is allowed?

Offline 1212FBGS

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Re: 500cc pushrod bike project
« Reply #29 on: October 19, 2008, 03:43:10 PM »
jim
What cha hiding behind the curtin oh great and powerfull Oz.?....
kent