downhull mtb with dirt bike engine

[mdd0127]

Sorry to double post. This is too cool and belongs in both catagories. Maybe with enough interest we can get them here at decent prices. fxbikes.com

[sloman]

50cc's starting @ 100lbs??? most 50cc dirtbikes are only a tad over 100lbs... I didn't see mention of price. Despite it using some mtb components, its still a motorcycle and would not be allowed on hike/bike trails which motorized vehicles (of any kind) are illegal. I guess I don't see the value over an just as agile 125cc or similarly small dirt bike which is PROBABLY (again, didn't see a price) in the same price range. The weight isn't much different, and the added weight of a real dirt bike is justified with added strength of the frame/components. The concept is cool though.

EDIT: Read through the website more carefully, I originally thought it was a modified MTB, which, more accurately its a modified dirt bike. There isn't a whole lot of MTB stuff on there other than a fork??

[ghettojeep]

50cc's starting @ 100lbs??? most 50cc dirtbikes are only a tad over 100lbs... I didn't see mention of price. Despite it using some mtb components, its still a motorcycle and would not be allowed on hike/bike trails which motorized vehicles (of any kind) are illegal. I guess I don't see the value over an just as agile 125cc or similarly small dirt bike which is PROBABLY (again, didn't see a price) in the same price range. The weight isn't much different, and the added weight of a real dirt bike is justified with added strength of the frame/components. The concept is cool though.

EDIT: Read through the website more carefully, I originally thought it was a modified MTB, which, more accurately its a modified dirt bike. There isn't a whole lot of MTB stuff on there other than a fork??
Dude, your comparing a full size bike to a friggen toy... And there is NO way your lifting any real dirtbike over a fence or throwing it around like they are.

Figgen sweet, prolly alot of scrilla though, that think looks like a blast. :smokin:

You can throw it on a bike rack, thats the advatage. Super fun, camping/jib machine, damn throw one on your crawler.

Way diff then a traditional motorcycle.

[sloman]

Dude, your comparing a full size bike to a friggen toy... And there is NO way your lifting any real dirtbike over a fence or throwing it around like they are.

They are comparing a toy to a full size bike..

product ______W(kg)____HP____HP/W
teamfx 124cc___40______17____.425
Honda CR500___100_____52____.481

I think its a great concept and very innovative and probably kick ass to ride. My concern is durability. I break shit all the time on my full size bike, can't imagine what carnage would come of a modified cr50 @17HP on MTB wheels/brakes. If you read the info you would see they changed a lot of things on the test bike that you see in the pics. They used a RM80 front wheel on the rear for durability reasons and upgraded brakes. The bike you an I would get (unmodified) would get mountain bike wheels and avid juicy 7 MTB disc brakes :eek: Yes, mountain bike disc's on a 100+lb bike + rider weight. You do the math. Can't think of any situation where I needed to throw my wr360 over the fence, but then again I try to stay on legal trails.

[B43]

SICK! I want one! :grinpimp:

[4HEAD]

Looking for price? Look harder. 6G for one....fawk that.

[mdd0127]

I found all the parts to make one for about $1200. I'll just have to make a frame,swingarm, tank, seat. I might build one this winter. If it works well and I can figure out the legal issues, I'd like to sell them here. I think I can keep quality up and keep the cost below $2500. Maybe less. 6K is insane and shipping would be about $1200. I'd buy a crf450x for less than that. Would anyone be interested?

[sloman]

Looking for price? Look harder. 6G for one....fawk that.
:barf: :barf: :barf:
WTF $6k!!! no thanks..

[4HEAD]

Id be down for something in the 2500 range. But will yours be titainium? The forks alone on these things are like 1300 or so....and then the rear suspension...looking at 400 -500.....

[4HEAD]

http://www.fxbikes.com/pdf/orderFormJune05.pdf

[mdd0127]

I've found forks with 9" travel on ebay going for around $300. The rear shock shouldn't be much. Do you really need titanium if it can be made strong and light with aluminum or steel? I wouldn't care if one was 110 lbs instead of 100 if I was saving $4k. I think the titanium is an option on the fx bikes too. Most of the mountain bike prices are WAY out of line. I can't believe anyone would buy a fork for $1300. For that much, you could have one built from scratch. I know these bikes and parts are nice but the cost is ridiculous.

[mdd0127]

I just looked at the order form and it's kind of confusing but it looks like the badass one would be closer to $8k + shipping.

[whistler110]

I don't know anyone who pays MSRP on MTB forks, you can pick those forks up new for $1000 canadian and there are lots of used ones around. MTB parts can be mixed with some MX stuff so you could play with wieght and strength. Avid Juicy 7's with and 8" rotor can stop a 50+ pound bike with a 250+ pound rider without problems so they could work, but knew stronger stuff will be out soon enough.

If you build one I'd be interested, but build it out of Aluminum. Ti and steel both have too much flex for this application, that's why no one in the bike industry wants a Ti or steel DH bike.

[mdd0127]

I saw a fuggin awesome rear wheel today at the bike shop. The tire was 3.7" wide. It looked mean! It had a single sprocket on one side and an 8" disc on the other. I talked to the guys at the bike shop and they seemed very optimistic about the idea. I agree that aluminum would be the way to go for the frame and swingarm. It's on. Get ready for spring release next year. I'm not quite sure if I can keep the cost under $2500 but it will be close. People are going to have to start riding something like these because of the gas prices.

[4HEAD]

Hey Mudd...Like i said. If you can build one that will hold up for under 3G. I will be in line for the first purchase. WERD

[mdd0127]

It's on like donkey kong! I'll try to have a tested prototype by next spring.

[ghettojeep]

It's on like donkey kong! I'll try to have a tested prototype by next spring.
Need some help? I bet that thing can do wheelies for days :smokin:

Man it looks like a good time.

[mdd0127]

The only help I need is a small business loan! LOL I don't make much money in Cortez so I'll have to save up for all the parts and build the frame/swingarm/tank in the meantime. I'm kind of in a catch 22 right now. I don't make enough money to get my rig going but as soon as I get it going, I have a second job at a body shop waiting for me. I've been looking into making them street legal but I'm not coming up with much. If I go to a 4stroke 200, the bike will weigh too much to make it worth it. Any ideas on tagging a 2 stroke? If I made one 49cc and put a centrifugal clutch and some dumy pedals on it it would be considered a moped by CO law. I was looking at getting a hobby title for them but the only state that does that is Wisconsin. Any lawyers reading this? HELP!!!

[mdd0127]

Update! The engines I'll be using in these will be 10hp 4 stroke 125's. My bikes will have enduro computers for speedos and led lighting. They will be street legal. I've found different gears available too. Right now it looks like the top speed with the gears and wheel size I'll use would be 55mph. Wheelies all day and 100 mpg. Who could ask for more?

[1985CJ7Laredo]

I want one of these! I used to a have a bike with a motor on it, but this is wayyyy cooler! :grinpimp:

[mdd0127]

The local bike shop is going to help me get all of the parts rounded up for the prototype. The D.O.T. just got back to me today about street legal tires that will fit the mountain bike rims. There aren't any---yet. I'm working on a couple of manufacturers. I'll update when I find a tire. These need to be street legal. I've figured out how to get vins and titles issued and the lighting won't be a problem. The tires are the only hold up. I'll be using aerospoke carbonfiber wheels, marzocchi 888 forks, hydraulic 8" discs(not sure which brand yet), fox 5.0 rear shock and a lifan 125cc 4stroke with a 4speed. As soon as I get all the parts rounded up and the legal issues figured out, I'll start working on the frame/swingarm/tank. I really need a business loan to start production but I can't expect any help until I get the prototype done and beat the crap out of it. Buying all the parts at retail would make the bikes really expensive and I want to build something that a regular joe can afford and ride to work if necessary. I'll have to order straight from the manufacturers in bulk to get the price down. I don't want to skimp on parts quality.

[ghettojeep]

I've been searching around for tires for my DR 350.

I'm not sure what size rims you are gonna run, I would assume a 21" as these are standard bike rims.

There are several front tires that would fit on a MB rim I think, for instance the Dunlop D606 is a tubed DOT approved tire that is recomended to fit on a 1.6" wide rim.

I'm not sure if this would be ideal to run F and R as you usually want a smaller back tire on a dirt bike, but on a mountian they are the same size.

I'm not sure what the bead differences are. But another option would be to lace MTB hubs to a motorcycle rim.

You can find rims in many different spoke patterns, and ones that are blanks. So basically if you can drill and lace a rim, you can hypothetically run anything that will fit between the forks and swingarm.

Wheels and tires can be done I think :D

[mdd0127]

The bead seat diameter on the mountain bike rims is 22". That's a great idea about lacing up a new rim. I want to use aerospoke wheels on this thing. I think they're stronger than spoked wheels. I would like to use the same diameter tire on the front and rear. When I get some money, I want to call aerospoke and see if they can make wheels specifically for this project. I really don't want to get into using dirtbike wheels because they are so heavy but I'm not sure the regular mountain bike spoked wheel can handle the torque. The carbon fiber wheels should be much stronger and they never need trued. Plus, they look really cool.

[mdd0127]

This has become a dream that isn't going to happen anytime soon. I hope somebody starts building these things at a decent price. They'll make a ton of cash.

[Kyron]

:D They need to be like mopeds,............. where you can pedal and/OR use the motor.

That way alot of the legal red tape is GONE :cool2:

[mdd0127]

Colorado law says to be a moped it has to have pedals and be less than 50cc. It's not worth building a 50cc. There really isn't much red tape. I need to find dot legal tires that will fit the wheels I want to use and file 3 forms with the mvd. This project has gone to the bottom of my priority list since the divorce problem. Unless I find a decent job soon, I'll probably be playing catch up for a couple of years. If someone wants to take this idea and run with it, I am available to design, build, and promote it. I'm want to relocate anyway. I just don't have any money. This will be a serious form of transportation here soon and the person that gets it going first will rake it in.