Old Guys V twin & sidecar

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indian22

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Dec 31, 2014
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For those who have followed my Old guys Simplex & Harley "Peashooter builds, thanks for your continued support. It is a marathon post and with the V twin & sidecar thoughts thrown in it has become cluttered & perhaps it is past time to start a new thread for what I hope is an entertaining & fun build.

I'm glad I delayed starting a new thread because enough time has passed that I've consolidated my options and have settled on using the Yamaha V-Star 250 cc V twin 5 speed for power. My wheels are 17" custom DOT certified 36 spoke units to which I've mounted 2.25" front and 2.5" speed rated rear tires. The sidecar will also run the same wheel with a spare wheel and tire mounted on the sidecar as well. Disc brakes on all wheels. The car will also feature spring and shock suspension.

This will be a soft tail design, with a single spring over air mono shock. The fork is a single spring girder much in the style of many early British manufacturers. The main frame shop built.

I've begun this build by concentrating on getting the moving parts right. I'm still working on these and will be until I get them right. Both the Simplex and Harley builds are 80 mph bikes riding on bike tires. Scary ride even for a brief time at those speeds. I hold both at around 40 mph during rides, with the occasional brief burst to 60 mph. The V twin should be a 90 mph bike at the least & I'm building it with this in mind 'cause I'd like to feel safe cruising at a steady 70 mph. This is to be a light motorcycle that exhibits some early classic styling, but safety trumps classic when appropriate.

I'd think the bike will weigh in at 200 lbs. or less and the sidecar will add 75 lbs. or so. The stock V-Star Yamaha weighs in at 325 lbs. & no sidecar. The V-Star Yamaha is listed at a max speed of 85 mph so 90 mph is probably a conservative estimate for the bike solo. Daredevil's, from the land down under, Yamaha V twin build on this forum cites right at 100 mph speed by the current owner, but I don't recall the weight of that build being recorded in his posts.

As an Old guy I'm less concerned with me pressing the speed boundaries for more than the brief burst, but other owners might some day. So I plan on building strong with good handling...manners. Wheelbase of 60" or less (V-Star 250 is 58") should complement higher speed stability & I plan on running a steering stabilizer when running solo (no sidecar).

Hope this post catches new readers up without having to go back to the Old Guy's Simplex thread. I will post photos as I go. Rick C.
 
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Ludwig II

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It is commonly agreed among sidecar pilots that the spare should be a back wheel as that's the most likely to puncture/fail. I can't state this from experience, but it makes sense to me.
 

indian22

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I had given this some thought & arrived at no conclusion. I really appreciate your input Ludwig, It makes sense & now verified I will proceed in that direction. Though the build involves 4 wheels I purchased 6 (3 front & 3 rear) all 17" and now I'm really glad I did. Now is an appropriate time to decide if the side car wheel should also be sized with the 2.5" tire mounted on a rear wheel since the rear axle bolt is a 12 mm and the front 10 mm, so the spare could then be employed on either rear or side car using a 12 mm axle. Flats on front are easier to break down and patch on the roadside of course...and there's always the auto club.

A couple of posts and already getting good feed back! Photo shows the drive sprocket & adapter to bolt up to the 6 bolt disc brake pattern with extra long 11 grade bolts. The 3 bolt hub adapter on the off drive side will secure a 6 bolt disc rotor adapter...to mount a 160 mm disc rotor. There is enough room to mount a second 3 bolt hub adapter to the drive sprocket as well which would really lock the sprocket to the hub. Rick C.
1106171540.jpg
 
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indian22

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Wheels and swing arm coming along and the forks came in. I will need to widen 1" to as much as 1.5" to mount a brake rotor.or two. Thick wall 3/4" tube used in both legs of the girder, brazed where appropriate and some nice TIG work on other fitments. Only 4" between drops, the legs are just 3.5" ID. As I thought before ordering it's pretty simple work to widen as much as required to fit wheel& tire. The spring is a big barrel 8" x 1.75". Since I'll be doing some fab work on the forks I'll probably beef up the drops enough to run 12 mm axle up front as well fo a bit more support.

I don't know how they will ride, but it's quite obvious that the Sunlite & Monarch forks, which I've used in the past & like, are pretty light weight in comparison to these, but then that's what I was looking for, a light weight motorcycle fork.

It's nice to have parts coming together both front and rear on the V-twin. Now if I can just get them to work together. Rick C.
1109171513a.jpg
 
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PeteMcP

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Rick,
I'm following this thread with interest.
With my DECOLINER build now wrapped-up, I too just purchased those same girder forks from a Far Eastern eBay seller for my next build. Scheduled to reach me here in the UK on Wednesday. Have to say I was really satisfied with the forks/frame/tank I previously purchased from cnolmotorsport in China for my Indian boardie tribute. Your overview here inspires me with confidence, so I'm expecting no nasty surprises.
 
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indian22

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Pete because of my special application requirements I will be making several alterations to this fork, though none directed toward adding strength to the basic design. The fork is way overbuilt for motorized bicycle use, but 4" between drops, 3/8"/10 mm axle & 26" length make it pretty clear that matching to cruiser style bikes was the design intent. I'd been searching awhile for fork alternatives & finding this one & at what I consider a bargain price, $100. less than the Ruff & $300. + less than similar Enfield style small motorcycle forks from India (nice ones though), shocked me. I was reluctant to order because of the low price, but fortunate I did.

I've actually orders in for a solid girder fork, which I plan to use in fabricating a Indian style girder/ leaf spring fork and another fork which is a rendition of the Schwinn Panther style single spring fork, both forks using what appears to be the same 3/4" tube diameter as the fork I just received.
I've two bikes already built that I'll likely use the two forks on. I'm kinda' spreading myself thin on projects, but given time and health I'll see them through.

I very much admire your Decoliner & look forward to following your future builds.

Rick C.
 
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Ludwig II

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Will you be adding a friction damper like here, using a hydraulic concealed in the spring or doing without one?

 
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indian22

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Ludwig I'd think the leather disk friction would be my choice for this one, but depends on how hard this fork rebounds. The problem is not so much the quality of ride or I would be using spring over air design to start with. The safety issue is my real motivator, so damping is important as well as adding additional fork stabilization for control at higher speeds. My Simplex Copper Gator doesn't exhibit control issues at 70 mph plus, even on rougher surfaces & the dual spring Sunlite fork does not feature damping, though I do run a steering stabilizer. For the V-twin I'll use both damping & a stabilizer.

I really like the collection of forks in your last post, yours? Rick C.
 
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Ludwig II

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No, these were from a page selling old Norton parts I think. It's a shame you're not close to me, you could spend days trawling through the stock at Yeomans.
 

indian22

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Ok Ludwig now I have directions. If I could borrow Pete's fine Morgan replica I'd be set for holiday!

Steve the heft is impressive. Width between the fork legs & the diameter allowed for axle bolt are really the only issues I see for light motorcycle use & both those are simple for a fabricator to remedy. Damping with traditional friction leathers, one on each side is also easily settled. The fasteners and toggles seem to be up to the task, yet lack an appealing classic look...also easily addressed.

I've started on & am still working on the rear of the bike, but will share some of my time with the forks as well. I suspect the "Keystone" style motor mount will also start to occupy a bit of my attention too. Unlike the true "Keystone" mount I fabricated for the Harley "Peashooter" this one will, though detachable, also serve as the pivot for the swing arm bearing assembly & jack shaft. The Keystone will also be the primary support element for my sidecar. As you can readily understand the Keystone mount has a lot going on & must function well for my V-twin/sidecar to be a successful design. I will invest some time with it.

As for the main tube frame I'll be using twin drop tubes from the neck to the Keystone motor mount both for additional rigidity and to allow front cylinder exhaust to exit between the two structural tubes . The Virago engine exhaust port is dead center of the jug & I'd like to not end up fighting tight bends to make the exhaust fit, been there....

Of course I also expect the finished work to be aesthetically pleasing so keeping proportions & contours in mind are as important to me as those issues dealing with safety, functionality & dependability. You can hide all manner of poor bike or auto construction with cosmetics, but bad proportions just can't be successfully masked. Rick C.
 
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indian22

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Another small victory in the war of the wheel. Disk brake adapter and 3 bolt hub adapter to locate & securely hold it and the rotor in position. The fasteners shown will be replace with button head/socket grade 11 fasteners. Rick C. 1114171433.jpg 1114171435.jpg 1114171436.jpg 1114171438.jpg
 
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PeteMcP

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Rick,
My girder forks arrived bang on schedule in today's mail.
No complaints whatsoever - other than grinding my teeth at the 33 pounds sterling duty I had to pay UK customs prior to taking delivery.
I ditto your comments re the excellent quality of these forks. They will be perfect for my upcoming build.
Carry on.
 
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PeteMcP

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Whisper this, right. But the 33 quid customs charge on the forks was based on the seller under-declaring the shipment's value (at my request) as being only US$60. Imagine what I'd have had to pay otherwise.!
So let me get this straight Rick. In the US you pay zero duty to import stuff like this from China? Seriously? I understand that certain imported stuff is 'zero-rated' so far as customs duties are concerned - but why do motorcycle forks slip under the net?
Last thing I want is to get all political - (this is NOT a thread hi-jack) - but it makes me wonder why we dumb asses here in the UK put up with this kind of legalized 'mugging' from our government. And don't get me started on petrol (gas) prices. Which means that thanks to exorbitant taxation, we in the UK pay more than double the price of our stateside bretheren. It's not that long ago when petrol in the UK was the equivalent of US$9/gal. Tell me your country wouldn't grind to a halt with gas priced at that level.