Author Topic: 500cc pushrod bike project  (Read 56438 times)

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Offline JimL

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500cc pushrod bike project
« on: September 16, 2008, 03:13:31 AM »
Been tinkering for a while.  I'm not really sure this will work, but I've turned a shaftdrive engine sideways to run through a jackshaft (to get a better gear ratio).
- New engine came from an auction about 20 years ago (I think it was $35 or so)
- 68" wheelbase
- 27.5 degrees rake using Suzuki GSX600 front end, swingarm, 17" wheels (donated bike that was "beat up" in parking lot of a bar!)
- trail is 7% of wheelbase
- still much work to do on the fork springs, etc.
- main frame tubes are 1 5/8", .122 wall DOM
- bottom tubes and members are 1", .120 wall DOM
- more stiffening to come
- output drive will be to an old Honda countershaft (set up to allow easy countershaft sprocket changes (many choices).
- Kawasaki H2R fairing, that will need lots of modifying, but we use what we've got in this business

This projects name should be "Willitrun?"
Regards, JimL


Offline oz

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Re: 500cc pushrod bike project
« Reply #1 on: September 16, 2008, 11:49:00 AM »
Cool What is the engine it looks like a CX500 but its a bit hard to tell from the photos if it is there is a Turbo version of that motor but you probably knew that anyway.I like to see something away from the norm and you certainly have it there NICE ONE.
TTFN OZ.
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Offline Nortonist 592

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Re: 500cc pushrod bike project
« Reply #2 on: September 16, 2008, 03:05:23 PM »
Thats an interesting set up.  Its great to see another push rod coming out.  Where are you located?  Is this a Bonneville only or will it see El Mirage?  Good luck with the build.
Get off the stove Grandad.  You're too old to be riding the range.

Offline 1212FBGS

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Re: 500cc pushrod bike project
« Reply #3 on: September 16, 2008, 03:41:18 PM »
the output shaft and trans cover are not strong enough to support a sprocket...you will have to build a bearing support to support the other side of the sprocket... i will try to post some pix of ours
kent

Offline JimL

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Re: 500cc pushrod bike project
« Reply #4 on: September 17, 2008, 12:13:24 AM »
The engine is same as CX500.  I've got CX650 carbs for it, and found the guy that has cam grind as used on the Honda flattracker for Freddy Spencer (they built a 750 out of one, turning it sideways like mine, but got rid of the "left" case).  I lucked out and found an old Hooker exhaust that I can cut and turn.  A few years back Hooker found some old motorcycle exhaust systems while cleaning out a warehouse (true story).  They sold them off for the scrap metal weight and I picked up several oddball items.  Fun stuff!!

I'm keeping it simple by using the jackshaft method, since the engine will fit behind the old AirTech H2R fairing.  I make most stuff by hand, and do a lot of machine work with a file, which keeps me happy in my spare time!  So far the biggest expense was an $85 gasket set.

I'm building this in Long Beach...planning to run Bonneville next year (if it works, of course).  That will be the "40th year" since I ran a 450 Honda out there....seems like as good a reason as any, don't you think? :lol:

thanks for the interest...when I get the jackshaft system set up, I'll post some pics...I will be using an outboard bearing, in the sleeve I cut off the driveshaft (there's a dampening system inside that causes some trouble, as described by Kent).
Regards, JimL

Offline panic

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Re: 500cc pushrod bike project
« Reply #5 on: September 17, 2008, 01:03:34 PM »
Are you planning on sectioning the H2 fairing to reduce the width?
If yes, straight through the center, or???

Offline 1212FBGS

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Re: 500cc pushrod bike project
« Reply #6 on: September 17, 2008, 06:44:04 PM »
jim
before you get too deep, you should come down and see what we did on randy's bike.
kent

Offline JimL

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Re: 500cc pushrod bike project
« Reply #7 on: September 18, 2008, 02:22:14 AM »
Thanks, Kent...I'll give you a call when I'm done with next weeks travel. 

JimL

Offline wolbrink471

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Re: 500cc pushrod bike project
« Reply #8 on: September 18, 2008, 08:44:51 AM »
the output shaft and trans cover are not strong enough to support a sprocket...you will have to build a bearing support to support the other side of the sprocket... i will try to post some pix of ours
kent

first off.....thanks for the fenders! Great stuff and helped us see 132+ on the KX!

i would love to see pictures of your jackshaft!

ummmmmmm.............errrrrrrrrrrrrrrrrrrrrrrrrrrr

I meant to say.....It would be great if you could post photos of the final drive assembly you use.

seesh...sorry everyone

Is there a noticable loss/drain of horsepower?

Do you use it for gearing reasons also? or to reduce the span of a single chain?

Thanks

Mark
« Last Edit: September 18, 2008, 08:48:25 AM by wolbrink471 »
more information about the World's Fastest Dirt Bike at...... www.wolbrinkrace.com

Offline JimL

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Re: 500cc pushrod bike project and definition of "reverse learning"!!
« Reply #9 on: October 04, 2008, 02:37:27 AM »
Yesterday I learned the definition of "reverse learning".  I got to visit Kent at AirTech, who was kind enough to show me around his projects.....also had a visit with his friend, Randy, who's already figured out what I was trying to accomplish (though I sure had some of it wrong!)  I experienced the "reverse learning" process in just a few hours....where all your "for sure" conclusions turn around on you.

I had thought I had some pretty good ideas....but left his shop feeling pretty humble.  For any readers of this board:  About the time you think things are going along well....that's the time to talk to the folks with the real experience.  Your time will be WELL spent.Big thanks to Kent and Randy for steering me away from some difficult troubles!   :-) 

I'll post some more pics, soon, I forgot my camera this evening.

Regards, JimL

Offline isiahstites

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Re: 500cc pushrod bike project and definition of "reverse learning"!!
« Reply #10 on: October 04, 2008, 10:00:50 AM »
Yesterday I learned the definition of "reverse learning".  I got to visit Kent at AirTech, who was kind enough to show me around his projects.....also had a visit with his friend, Randy, who's already figured out what I was trying to accomplish (though I sure had some of it wrong!)  I experienced the "reverse learning" process in just a few hours....where all your "for sure" conclusions turn around on you.

I had thought I had some pretty good ideas....but left his shop feeling pretty humble.  For any readers of this board:  About the time you think things are going along well....that's the time to talk to the folks with the real experience.  Your time will be WELL spent.Big thanks to Kent and Randy for steering me away from some difficult troubles!   :-) 

I'll post some more pics, soon, I forgot my camera this evening.

Regards, JimL


Kent and Randy helped me with lots of advice and parts for my bike and steered me clear of many mistakes I would of made, hell they even told me something wouldn't work and I forgot or tried it anyway only to find out that they were right, you really can't find much better help or dedication to the sport than those two.

Randy's 500 is a pretty dam fast 500..........

Offline guttley782

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Re: 500cc pushrod bike project
« Reply #11 on: October 05, 2008, 12:25:26 PM »
It looks great! I like singles myself, and think sometimes the simplicity just seems right. Keep up the good work and keep the information coming! Gabriel.
An eccentric Englishman building a motorcycle streamliner with the help of a few friends!

Offline JimL

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Re: 500cc pushrod bike project
« Reply #12 on: October 14, 2008, 02:25:53 AM »
Oops...trouble with a post.  I'll try again.  Hopefully I'm not doubled up, here....

A little progress on the bike project....added a 1" x .125 wall tube to pick up the other engine mounts on right side of the block.  I also added a steel shelf under the engine to slide it in and out the left side of the frame.  The steering head area is now boxed to the 1 5/8" x .125 wall top tubes and 1" down tubes.  Some additional braces have been added.

The header pipes are tacked together at 27.28" from valve seat to end of primary....there will be 27" megs (shallow angle) at max 3" (my '69 LSR 450 ran 5 degree megs at 3 1/2").  The forward header had to jog around the clutch, in order to keep the end of the meg behind my right foot.

I'm using the Suzuki front brake master cylinder for the rear brake, because I don't have enough room for my brake foot with the two megaphones.

The jackshaft is started, using the trans input shaft from a Honda CB500T (450 would work).  The clutch basket broach is the same as the countershaft sprocket, so sprockets are cheap and easy to get (13T to 17T).  I'm using 15T on the engine output shaft and 16T on the jackshaft (525 chain), with 530 chain and "whatever works" on the final drive.  I'm wanting to enclose both chains and set up a "metered feed" chain cooling system, draining into sumps during the run.  I'm considering using brush type distribution on the bottom run, to get good application without too much volume.

The jackshaft bearings are 20mm and 25mm pillow blocks (which fit the 500T shaft perfectly), rated for 5000 RPM continuous at up to 455 lbs (can't make that much with my little engine!).  At lower RPM, the load rating is much higher on these pillow blocks.  I'll use a 1.250" pillow block on the outboard side of the output shaft, sprocket carrier, to reduce bending load on the output shaft/bearing in the left case.

Here's two pics.

Offline oz

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Re: 500cc pushrod bike project
« Reply #13 on: October 14, 2008, 11:59:49 AM »
Looking Good
Newcastle born and bred a City built on Coal and Steel and a people built of stronger stuff

Offline Jonny Hotnuts

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Re: 500cc pushrod bike project
« Reply #14 on: October 14, 2008, 12:12:38 PM »
What is that motor sitting on the bench?

Love the project.


-JH
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"Sometimes it is impossible to deal with her, but most of the time she is very sweet, and if you caress her properly she will sing beautifully."
*Andres Segovia
(when Im not working on the car, I am ususally playing classical guitar)