My little race bike
- Thread starter Skyking
- Start date
Rad build so far. It's similar to one of my bikes. I have a Greenline DS-20. Which is a clone of those old duel suspension BMX bikes from the mid to late 70s. Mainly cloned after the most popular one of those times, the Yamaha Moto-Bike. The original Yamaha bikes now days are considered by many the holy grail of the BMX world. Some of the Japanese imported versions go for $5k+.
You can see the initial mock up of my BMX bike here if ya wanna: http://motorbicycling.com/showthread.php?t=55562. This bike is still in mock up and will start again on it when I finish my current build. I have too many bikes and not enough cash to support my habit.
I wanna clear something up that could be a little confusing to some reading this thread. Bicycles are weird in which I mean they use the height of the tire to determine wheel/tire size. In other words BMX bikes are called 20" bikes but the wheels themselves are 16". Mopeds and Motorcycles use the less confusing way when talking about wheel/tire size.
I ended up putting a 7 speed hub on my BMX and used a SBP shift kit. The reason I did this is because when the rear suspension flexes, since the output gear wasn't close to the swing-arm pivot point, the chain will have a lot of slack in it. What do you plan to do to combat that? I'm skeptical about using a spring loaded chain tensioner for this application. I saw another guy on here build a silver fox like yours with just a china girl with no jackshaft or shift kit. Maybe his didn't compress enough to make a difference. It was an older thread so I never got to ask how it was.
You can see the initial mock up of my BMX bike here if ya wanna: http://motorbicycling.com/showthread.php?t=55562. This bike is still in mock up and will start again on it when I finish my current build. I have too many bikes and not enough cash to support my habit.
I wanna clear something up that could be a little confusing to some reading this thread. Bicycles are weird in which I mean they use the height of the tire to determine wheel/tire size. In other words BMX bikes are called 20" bikes but the wheels themselves are 16". Mopeds and Motorcycles use the less confusing way when talking about wheel/tire size.
I ended up putting a 7 speed hub on my BMX and used a SBP shift kit. The reason I did this is because when the rear suspension flexes, since the output gear wasn't close to the swing-arm pivot point, the chain will have a lot of slack in it. What do you plan to do to combat that? I'm skeptical about using a spring loaded chain tensioner for this application. I saw another guy on here build a silver fox like yours with just a china girl with no jackshaft or shift kit. Maybe his didn't compress enough to make a difference. It was an older thread so I never got to ask how it was.
bairdco
a guy who makes cool bikes
I had a yamaha motobike I got from my friend sin (he's on here, can't remember his forum name.)
Rebuilt and restored it and sold it for $550. And that took months of lowballers before someone stepped up to my price.
Dunno about your "5k" estimate. I've seen a few for sale that were still boxed up and found in bike shop basements, unsold, and they were around $1000.
Not arguing, and don't wanna hijack this thread, just sayin'...
Rebuilt and restored it and sold it for $550. And that took months of lowballers before someone stepped up to my price.
Dunno about your "5k" estimate. I've seen a few for sale that were still boxed up and found in bike shop basements, unsold, and they were around $1000.
Not arguing, and don't wanna hijack this thread, just sayin'...
My motor was originally on a GoPed. It's a 2 wheel scooter. Kinda like a big skateboard. I'll post a picture of the motor tomorrow when it's light out.
Thanks. My mount is due Monday via FedEx. They usually deliver here before noon. So I should have it going well before dark. It's not going to be a drop-in fit like was initially advertised. I'll post pics as I go.
Not really a clone. It's a Chung Yang GP460, and they give a new meaning to made in China(in a good way). Very close to Zenoah standards, and a little bit cheaper, and more readily available. All kinds of upgrades available that just are not available for the Zenoah of the same size. Don't ask me why. I would prefer the Zenoah.
I think around 4HP out of the box. This one is far from being out of the box. Fully ported, and port matched for the reed valve. Cylinder reed valve, and ported piston. Stuffed crank. 19mm Walbro with a 16mm Venturi. I would like to put a bigger carb on it, but I haven't found the right set-up yet. It's got a DDM Dominator side bleed pipe that's like a three speed transmission. It's an amazing phenomenon to experience. It has three distinct power increases as the rpm's rise to more than 14,000., and it all starts at around 6,000. It's not even broke in yet.
I think around 4HP out of the box. This one is far from being out of the box. Fully ported, and port matched for the reed valve. Cylinder reed valve, and ported piston. Stuffed crank. 19mm Walbro with a 16mm Venturi. I would like to put a bigger carb on it, but I haven't found the right set-up yet. It's got a DDM Dominator side bleed pipe that's like a three speed transmission. It's an amazing phenomenon to experience. It has three distinct power increases as the rpm's rise to more than 14,000., and it all starts at around 6,000. It's not even broke in yet.
Oh yah, FedEx delivered my mount kit. It's a piece of ****, but I may be able to make it work. Three pieces of cut, and bent cold roll plate. Sharp ragged edges, and corners everywhere. The only hole that is pre drilled is for the right side bearing. A bag of nuts and bolts, and washers. A couple of plastic chain rollers, Two little predrilled strips of alumininum, and a spring for making a chain tensioner out of. 3 exhaust pipe clamps that are the wrong size, and a 9, and 10 tooth primary gear to run the chain down to the BB. I am underwhelmed to say the least. So far I've only filed all the edges and corners smooth. I've got a bunch of holes to locate and drill. It looks like I'll probably just weld the plates together instead of trying to drill, and bolt them together. I may even go ahead and weld it to the bike instead trying to use the exhaust clamps to hold it in place. It's gonna take some time no matter what route I choose.
Sorry for the confusion bairdco. What I said was, some of the Japanese imported models can get up to $5k(mint condition). Not the standard model like you are thinking of. These where imported Japanese models that are fully decked out with drum brakes front and rear, bigger better fenders front and rear, different handlebars as well as a few different paint jobs and accessories that only came on those models. Last summer i saw two on ebay that where mint and they where asking and getting ~$5k. I cant find one for sale right now in that condition but this one (http://www.ebay.com/itm/VINTAGE-BMX...2708-RARE-GREEN-YAMAHA-MOTOBIKE-/361248329333) is despite saying its a rare color its not the rarest color. This one is missing quite a bit and is quite beat up and they are asking $1,400 with shipping.
Sorry to get a little off track sky. Great choice on engine. Those GP460s scream! Looks like you've got a good project going. Your mount sounds like most "kits" in this hobby(most hobbies) haha. They'll do the heavy machining for us but we gotta do all the finish work! Lookin forward to see this one come along.
Got any paint plans yet?
Hey, no prob Rob. It's all interesting, and basically the same subject matter, but I think a lot of folks may miss out on this info because of it being in my thread. I think you should re-post it under a new header so that everyone has the benefit of seeing it.
The thing with my kit, is that when I ordered it( about 2 or 3 months ago), it was going to be basically ready to install, and adjustable for varying bike frames, and a choice of the clamp sizes to accommodate the various seat post, and down tubes. Have since been told that the 1" clamps that I ordered are not available. BS! This vendor says one thing, and later something entirely different happens.
BTW: just for information purposes; you can buy these motors in stock configuration, and includes the Walbro carb, air filter, pull starter, engine cover, fan cover, muffler cover, the three shoe clutch, clutch bell, clutch bell housing with sealed bearing, and the muffler, for $265 plus shipping from davesmotors.com. They are rated at 4.2 HP, and the quality is far superior to the ChinaGirl motors. They sell different clutch springs to change the rpm's that it engages at, along with many other performance parts to upgrade the horsepower, and torque. They also keep a full line of replacement parts, and they are an excellent company to do business with.
Seems like a no brainier to me.
Seems like a no brainier to me.
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UPDATE: not even cold roll, just some piss poor mild steel plate. Put a little heat to it, and warps all over the place.