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Old 04-06-2011, 03:19 PM
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halfevil333 halfevil333 is offline
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Join Date: May 2010
Location: florida, USA
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Default Re: Crazy Speeds

I cruise an easy 35-40 all day, trying never to slow for anything less than certain doom!...
Take into consideration however; I only weigh about a buck fifty, I've cleanend and port-matched both intake and exhaust, better plug &wire, tuned carb', better airfilter, good grade oil I think is pretty important too!...& of coarse, 36t. sprocket
I'm hoping to reach Bairds' speeds once I do some more kanoodling!!!

...oh, and as far as the suspension issue, I can adjust the spring tension on me home-made monarch-ish forks according to how springy(for beach cruising) or stiff(haulin azz) I want!

Last edited by halfevil333; 04-06-2011 at 03:23 PM.
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Old 04-06-2011, 10:32 PM
5-7HEAVEN 5-7HEAVEN is offline
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Default Re: Crazy Speeds

My friend Hawaii Ed runs crazy speeds over 50 mph on the flats. He's tricked out his HT engine and runs a shift kit.

I run either a 4.25 hp GP460 engine or a 2.8hp Tanaka 47R on my shift-kit bike.

My top speed was 45 mph. The engines have power to spare, but the rider backs down. I love the cruising speeds between 25 mph and 35 mph. Over that, and it's a race with Death for me.

Besides, how am I going to explain to the judge that I was going over 10 mph past the speed limit?
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Old 04-07-2011, 10:14 PM
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ToxicAz520 ToxicAz520 is offline
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Join Date: Mar 2011
Location: Tucson,Arizona
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Default Re: Crazy Speeds

I have the suicidal coaster brake. I been trying to find a good brake or at least save up for a regular one.Then I can get a hd wheel with a freewheel. Wanna try to figure out how to put disc brakes on
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Old 04-14-2011, 02:54 PM
djnutz djnutz is offline
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Join Date: May 2010
Location: South Dakota
Posts: 19
Default Re: Crazy Speeds

I have the 66/80 Flying Horse. It is in a 15 yr old Raleigh mountain bike frame. I have also recently upgraded to the CNS racing carb. The old bike frame was 20+ year old heavy steel frame with steel rims. The "new" frame is aluminum with aluminum rims. The old bike would just barely hit 30mph on the flat and there was a lot of vibration. With the new frame and other changes I can easily cruise at 35. This really feels plenty fast enough for me. Everything rolls smooth with no vibrations at all. My top speed on a bicycle was on RAGBRAI last year on my Trek road bike. (yes I am a spandexter) I hit 50mph on a downhill and it was the scariest thing I have done on a bike. If I wanted to go that fast on a MB, I would just buy a motorcycle.
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Old 04-14-2011, 03:30 PM
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DaveC DaveC is offline
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Location: Boise, ID
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Default Re: Crazy Speeds

I don't think my bike could hit 30 going downhill Then again, I have 28" wheels and the first thing I did was replaced the stock 41 with a 56 tooth gear. Speed here is not inportant, getting up hills is. From what I've read in the bike forums I might have one of the most modified motors as far as bolt on's go. Everything external has been up-graded. When I get a new 49cc I'll be tearing into the 66cc and modding everything possible to make more power and the up-grades needed to handle the output. Right now I've started on that; clutch improvements were needed with what I've done already. It now wants to wheelie when I start it! I have to lean forward to keep weight on the front wheel.

New motor the first of June, hopefully Spooky Tooth is back online by then
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Old 05-04-2011, 08:25 PM
Shorty Shorty is offline
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Join Date: Apr 2010
Location: McKinleyville, CA
Posts: 30
Default Re: Crazy Speeds

My first bike would hit 43 according to the radar sign by my high school. I was running a 66cc Raw motor, well tuned CNS carb, port matched, straight piped, and a 36t sprocket. I only way around 140, and took as much weight of my bike as possible. It also had really low front forks and the handle bars were low so I could lay down on it.

It was a rush goin that fast, man! Especially with only a coaster break to slow me down. And no, I'm not suicidal. I just really like going fast a lot. And if a wreck, I consider it my homage to the Holy Mother of Internal Combustion. LOL!

My new bike doesn't go nearly as fast... It hit 26 today according to the same sign. It has a 66cc RAW, not ported yet, stock muffler, 44t, and stock NT carb.
Im waiting til it broke in to try for a speed record!

Good luck, my fellow speed demons! And be safe out there!
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Old 05-05-2011, 04:13 PM
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James912 James912 is offline
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Location: Florida
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Default Re: Crazy Speeds

I have a 26in Shimano Deore mountain bike with a silver slant 2.67-2.89hp 80cc(technically 66-69)motor slanthead, stock spark plug, 44t, nt carb, stock exhaust and i used an app on my android phone and it said 23mph and it was still trying to catch up to my speed, and i still had like half throttle to go,but i backed off because of all the vibration. My hands were numb in seconds. I went a block in like 5 seconds. lol When i get the sbp expansion chamber and a better carb, airfliter itll go probably atleast 35mph.
Just my bike alone is worth $200. I got it at a yard sale for $40.00. Its one of those professional top of the line mountain bikes. I use the rim breaks that came on it. They work great. I can stop easily using either one seperately. The back takes a second or 2 longer.
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Last edited by James912; 05-05-2011 at 04:17 PM.
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Old 05-05-2011, 05:02 PM
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fall_down_stand_up fall_down_stand_up is offline
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Location: granbury
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Default Re: Crazy Speeds

I have a 26in cruiser bike with a 66cc Raw engine on it with a 44 tooth sprocket with stock everything....On flat ground without the wind blowing I have gotten up to 30mph once....
IF I CANT FIX IT,IT ISN'T BROKEN!....ummmmmmm so I thought....
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Old 05-05-2011, 09:31 PM
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mapbike mapbike is offline
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Location: Central Texas
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Default Re: Crazy Speeds

I GPS 39MPH with a 66cc slant HT, head has been seriously shaved, transfer ports polished and matched, intake deburred and cleaned up, exhaust depurred and polished real nice, manic port matched intake, good plug, boot, wire, extremely free flowing exhaust and I'm running a 36T sprocket.

This thing sounds like it's turning 10,000 RPM's at 39mph, I still dont know how people are getting these approx. 40+mph speeds out of bikes with a 36T sprockets.

I'd like to know what I'm doing wrong or maybe just failing to do to get over that 40mph hump....because I can't seem to get there with mine and it is a very strong high torque engine that pulls hills like crazy and is just a very good running engine, with a nice cruise speed of 30-32 with very little vibration, I hit 39MPH and it goes flat and she wont turn another rpm period, I would love to have it cruise nice on the flats at 35mph and top out at 40+mph maybe I need to put a 30T or 32T sprocket on it to get those speeds, not sure.

I dont always ride WOT, but when I do..I do my best to keep the rubber side down..Ride safely my friends!
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Old 05-06-2011, 06:29 AM
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Greg58 Greg58 is offline
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Location: Newnan,Georgia U.S.A.
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Default Re: Crazy Speeds

To be street legal in Ga. i bought a 48cc grubee, after break-in I have got 31 mph on flat roads 35 on downhill. The vibration is what i don't like, 23 to 25 is a nice ride for me.
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