670cc V-twin mini chopper beginning plans

Using a donor motorcycle is in my book cheating, not to mention, im doing this not just for the pride of having a unique ride, but also for the pride of modifying an engine that isn't originally designed for high rpms, to get those high rpms out of it, including having a balanced crankshaft, heavier valve springs, a balanced camshaft, and a billet flywheel, along with stronger rods fabricated, and using carbon steel bearings. My muffler will of course be an absorption, so it gets louder at higher rpms, but reduces backpressure.

Information update, the cassette gearing I have selected on bikecad.ca shows 30t-12t, with 39t and 52t chainrings. At 120 rpms (cadence) this gets me 33.2 mph in 7th gear with the 39t chainring. This gives me a ratio of 7.04 in first gear, using the jackshaft.

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i spent a total of eight hours designing this, getting every detail perfect. Equipped with 180mm discs, a battery box, a gas tank, highest quality rear derailleur, mag rims, 30t-12t cassette, 52t-39t chainrings, and all steel components. cables are routed within the frame, with one external guide for the accelerator cable. High temperature grease will be used to lubricate hubs and bottom bracket, with semi dry chain lube for the chain and derailleur pulleys. Headset will be lubed with light grease. Hub bearings will be carbon steel, as well as bottom bracket bearings. I estimate the total cost for this bike is about 3500. Performance parts for the engine I will wait on, as those will also be expensive. Once the bike is out of the fabricator's, I will put on the engine, which will have a 12t clutch engaging at 2000 rpm. Max RPM until performance upgrades is 4500, which gives me 2500 RPM to work with.
 
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At 4500rpm, your bike is geared for 50mph in 1st.
Keep schooling yourself.
My guess is that you'll run out of $$ before you put gas in the tank.
 
5-7HEAVEN said:
At 4500rpm, your bike is geared for 50mph in 1st.
Keep schooling yourself.
My guess is that you'll run out of $$ before you put gas in the tank.
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That is actually a very good guess. I have to save up enough to have this bike made, from the ground up.

So, this has basically become a sport chopper? I mean, 4500 rpm is the end of redline, so about 3500 at most, giving me 1500 rpm to work with, which I'm estimating is about 35-40? That winds up being about average for a decent sports car. It seems like you guys really want me doing a low gear ratio, but at that point, it'll be more for takeoff than anything else. I'm going to be using this bike for touring, which means speeds of 75mph pretty much constantly. Does your speed calculator take wheel size into consideration? Personally, I think the 7.04 ratio is perfect. 10:1 is too low for this engine, I think, because 212s can easily take off with that. But you say that 7.04 is too high? Though you said yourself that this engine will need a higher ratio, and its triple the size of a 212, so I think 7:1 is a good compromise. ****, I've heard of 212s running 6:1, which is higher than what I've got now...

Hows the design of the bike though? Will it be strong enough?

The upper gap is where the gas tank is, with the bottom one being the battery box. I also have a backup mid drive electric motor, just in case, which is powered by the battery, and ill probably have some other kind of electrical system in place to charge the battery as I pedal. Headlights will be the brightest crees I can put on it, and the tail lights will be hooked to the brakes and headlight. I will also have turn signals on my mirrors, and on the seat stays just above center.
 
I think you're in over your head.zpt

I'd suggest you shelf this project, do more research and improve your fabrication skills.

If you haven't built a motorized bike before, start with a simple China Girl install on a mountain bike first.

Save up for that.
 
5-7HEAVEN said:
I think you're in over your head.zpt

I'd suggest you shelf this project, do more research and improve your fabrication skills.

If you haven't built a motorized bike before, start with a simple China Girl install on a mountain bike first.

Save up for that.
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I'm always in over my head, no matter what I do. But I also always get things done.
I think you misunderstood. I'm not fabricating it myself. I'm paying to have it fabricated for me. I wouldn't even try to fabricate this thing.

I already built a motorized Kent road bike with a china girl, and blew out the spark plug core. I have a couple threads for that. Top speed was 33 mph. And this isn't my next build. I'm working up towards this, after building a couple basic 212s, a 301, and then a 420. Each with slightly different gearing for different purposes. My 420 will be a freight bike, capable of reaching city street speeds and not much else. It will be mainly for hauling a lot of groceries or furniture or that kind of thing. My 301 will be my mountain climber/dune bike. The 212s will be a cruiser and a long hauler. The long hauler will be geared for highway use, but with a poor loaded acceleration. Just as this 670 will be a touring bike, built for highway use and comfort
 
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So you're not building it yourself?
The"fabricator" is doing the bike?
Then for sure you'll run out of $$.

If you think this bike's gonna cost you $3500.....
double that amount.
 
The only parts that aren't really custom are the forks, the front wheel, the handlebars, the seat and post, and the tires. The chain, rear wheel, frame, and cassette will be custom, so that drops the price down a few hundred. I contacted a bicycle fabricator for a quote. Should be receiving one in a few days. I included the cad file that was made with the model for bikeCAD.ca.
 
xXNightRiderXx said:
The only parts that aren't really custom are the forks, the front wheel, the handlebars, the seat and post, and the tires. The chain, rear wheel, frame, and cassette will be custom, so that drops the price down a few hundred. I contacted a bicycle fabricator for a quote. Should be receiving one in a few days. I included the cad file that was made with the model for bikeCAD.ca.
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Did you mention to the fabricator what you intend to do with this frame? If you did, I'll bet he refuses to do it.
 
xXNightRiderXx said:
The only parts that aren't really custom are the forks, the front wheel, the handlebars, the seat and post, and the tires. The chain, rear wheel, frame, and cassette will be custom, so that drops the price down a few hundred. I contacted a bicycle fabricator for a quote. Should be receiving one in a few days. I included the cad file that was made with the model for bikeCAD.ca.
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Better make that front wheel custom. That way, when you hit the pothole at 70mph, it won't "taco" and kill you..duh.

You talk about your $15 cassette being custom. How much will it raise the cost? Another $15? If the fabricator does it, that's another $50.

You best be customizing your brake system to stop this 140mph bicycle.

Tires need to be custom. There's no 140mph speed-rated bicycle tires.
Check with Goodyear. Ask for Bonneville tires.

I've never heard of a custom-made chain.

You could place your order at the SRAM Industries. Ask for Jess Joaquin at 244-373-2637. Just make sure it's made in America, not foreign countries. Quality control.
 
Use Mag Wheels.
Use hydraulic MOTORCYCLE calipers.
The limits of bicycle tires haven't really been tested, but if any tire explode son a motorcycle, you're going to get injured.
 
5-7HEAVEN said:
Better make that front wheel custom. That way, when you hit the pothole at 70mph, it won't "taco" and kill you..duh.

You talk about your $15 cassette being custom. How much will it raise the cost? Another $15? If the fabricator does it, that's another $50.

You best be customizing your brake system to stop this 140mph bicycle.

Tires need to be custom. There's no 140mph speed-rated bicycle tires.
Check with Goodyear. Ask for Bonneville tires.

I've never heard of a custom-made chain.

You could place your order at the SRAM Industries. Ask for Jess Joaquin at 244-373-2637. Just make sure it's made in America, not foreign countries. Quality control.
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Thanks for the resources.
I've hit potholes at 40mph before my gasket blew and had no damage whatsoever come to my 700x32c tire or rim, but I will take that into consideration. Five spoke Mag wheels are already on the order for this bike. The brakes are 180mm hydraulic disc brakes with cross cut rotors.

All the customization really is is just slightly wider spacers to accommodate the slightly thicker chain. The links, instead of being .2mm will be .6mm thick on each side.

I'm going to be taking courses at UTI's motorcycle institute on phoenix, so I can be a factory certified Harley Davidson technician, both early and modern models. That's my funding right there.
 
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xXNightRiderXx said:
Thanks for the resources.
I've hit potholes at 40mph before my gasket blew and had no damage whatsoever come to my 700x32c tire or rim, but I will take that into consideration. Five spoke Mag wheels are already on the order for this bike. The brakes are 180mm hydraulic disc brakes with cross cut rotors.

All the customization really is is just slightly wider spacers to accommodate the slightly thicker chain. The links, instead of being .2mm will be .6mm thick on each side.

I'm going to be taking courses at UTI's motorcycle institute on phoenix, so I can be a factory certified Harley Davidson technician, both early and modern models. That's my funding right there.
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Yeah, there's not that much difference between 40mph and 70mph.

Your custom cassette and derailleur will easily accommodate .8mm(.031") wider chain.

"That's my funding right there."

Now there you go! Financing this project's all taken care of.
 
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5-7HEAVEN said:
Yeah, there's not that much difference between 40mph and 70mph.

Your custom cassette and derailleur will easily accommodate .8mm(.031") wider chain.

"That's my funding right there."

Now there you go! Financing this project's all taken care of!dance1
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Do I sense some sarcasm?

I think that's a bit more sarcasm.

I honestly can't tell if that is actually sincere. But I think that is also sarcasm because of the dance thing.

I did say no damage came to my 32c tire at 40mph. The new tire is larger by 6mm, and thicker than the cheap crap that came with that WalMart bike.

.6mm added on each side is a grand total of 1.2 mm thicker chain, which increases the strength of the chain a lot. The custom cassette is designed to accommodate this while also being able to fit on a normal freewheel. So no, it wont easily accommodate the wider chain because the spacers have to be exactly .7mm wider. I mean, 700 microns is small when you are comparing it to something that is already 2.3mm. The derailleur cage will need to be 1.4mm wider, but the size of the sprockets need not change.

As a factory certified Harley Davidson technician, I can diagnose any problem with any Harley and have the capability to fix it. Which gets me paid. I can go to any Harley Davidson dealer, and be hired on the spot (possibly, not definitely), getting paid by the end of the week. That will be two years from now however, as the courses provided by the motorcycle mechanics institute take 14 months to complete with a factory certification. And Harleys are common here in Vegas. Particularly because there's a hells angels club on my street. I've seen a lot of Harleys in that driveway.
 
I'm sorry for the"dance emoji".
I take it back.

However, don't confuse 700 microns with .7 mm.

700 microns x 1,000 =.7mm
 
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5-7HEAVEN said:
I'm sorry for the"dance emoji".
I take it back.

However, don't confuse 7 microns with .7 mm.

7 microns x 100,000 =.7mm
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1m=100,000µm. 1mm=1,000µm. Therefore 700 microns equals .7 millimeters. 700,000 µm is 7 meters. 7 µm is .007 mm. It's a badass number for sure, but not the right one.

I'm sorry if I couldn't tell whether that dance was sincere or sarcasm, its hard to read tone in text.

Ultralight, I put things in text so I have it out of my head. The way my head works makes it very difficult to retain any thoughts, so I have to put them down on a screen or paper to be able to keep it on track. I also have a hard time with memory, but then again, I am a stoner, lol.

However, that doesn't mean I idle down the road or drive faster than I should, or drive like I'm drunk. Fµ(k the government for making pot as bad as alcohol. If anything, alcohol and tobacco have much higher rates of dependency than marijuana, and cause much more harm than good. I'm self medicated, for depression, autism, and ADD, and pot has worked ten times better than any prescribed medications. And POT DOESNT KILL, right?
 
Oooh.....you GOT me!!

Sorry, I'm so used to being right.:-||

Thanks for letting me know you have issues, stoner.

I'm not gonna be sarcastic any more.

Hey, did you get the joke:

Jess.....Just.....
Joaquin.....Joking.

Ok, no more. All in fun.
 
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5-7HEAVEN said:
Oooh.....you GOT me!!

Sorry, I'm so used to being right.:-||

Thanks for letting me know you have issues, stoner.

I'm not gonna be sarcastic any more.

Hey, did you get the joke:

Jess.....Just.....
Joaquin.....Joking.

Ok, no more. All in fun.
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Hahaha, I didn't get that.

Yeah, knowing someone has issues changes a lot. I'm still learning how to cope with them, even though I've had them all my life. My parents started me on prescription medication at 5 years old, and took myself off them at 17. Soon as I did, I noticed huge improvements related to my attitude, and aggression, but I also noticed that I had major depression and anxiety.

All those pills did was cover that up. I started smoking weed two years after that, and I noticed that I was happier, less anxious, and could actually think properly. I still need prescription medication though, to truly treat my depression and ADD, such as Prozac and vivanse, but for my social awkwardness brought on by my autism, I don't think there is any medication besides THC that can help.

I don't catch on to social cues very well, so I try to keep myself out of situations where I need to be able to read those cues, but it doesn't always work. So I use my business attitude, which is straight to the point, and always honest.

Thanks for trying to understand 5-7, but there are some things that are very hard if not impossible to understand without dealing with it yourself. I don't really understand my own conditions that well.
 
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