The HF Greyhound Challenge

GoldenMotor.com

michaelgrav

New Member
Sep 14, 2009
122
0
0
sf bay area
Awesome Man
I grew up with 55 chevys & daytona chargers but I love this bike hobby!
and you guys blow me away!.flg.
2 engines there be a lot of shaken goin on! Like to see you make commuter out of that
 
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MaxPower

New Member
Jul 1, 2009
551
1
0
Sierra Vista AZ
Does anyone happen to know the dimensions of the harbor freight engine with and without the gas tank? Just trying to figure out if it’ll fit in my bike. Also, what is the idle rpm of the engine? The user manual says it’ll max at 3600 RPM stock.
 

tyrslider

New Member
Sep 26, 2008
958
2
0
RainCity
Max,

It idles at around 1200, I'll get you dimensions this eve if no one else has by then. This motor will fit most adult bicycles.

brnot
 

tyrslider

New Member
Sep 26, 2008
958
2
0
RainCity
Max,

Height is 8.5" w/o tank and exhaust, length is just over 11" and width is 11". It sits high in the frame. If you measure from the point where the seat tube meets the top tube forward 11" (level) and down 8.5" (perpendicular) and have not run into your down tube, you've got room. Less height is required if your top tube angles or curves up from the seat tube. Evan.
 

MaxPower

New Member
Jul 1, 2009
551
1
0
Sierra Vista AZ
Thanks a lot. I really like the set up. I'm having a hard time waiting for the production kit. If its under a billion dollars I'll buy one. I'm guessing you have no preliminary price estimate. just thought I'd try again. Peace
 

tyrslider

New Member
Sep 26, 2008
958
2
0
RainCity
Max,
It's no secret that we're trying to keep this kit at right around $500 for basic, everything you need, 1 speed kit. The idea is that everything you get is an upgrade (by "upgrade" I mean wrought from the callused hands of your hard working neighbors) from the usual Chinese kit items and you get it all at a midrange price ( a little more $ than Chinese kits and a bit less than the domestic alternative). You'll get, in addition to the WhisperDrive system, a custom, sprocket, airfilter, exhaust and motor mount. An upgraded throttle and Tsubaki #41 chain will also be included. The gas tank as seen on my test bike will be from the motor. There'll be further upgraded kits available w/ frame mt tanks etc. Thanks for the feedback! Evan FBC

Also thanks everyone for taking a sneak peak at the youtube video of our 1st test bike!

YouTube - firebellycycles's Channel

P.S. forgot the NGK Plug and Cap
 
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Hi Max,

HF motor approx $80.00 on sale.
Q-Matic drive $259.75
Subtract $329.75 from $500.00
Leaves $170.25 for gas tank, motor mount, throttle controls, chain, rear sprocket, etc.

Bet ya can build a nice 4 stroke MB for $500. or less using the well known & well tested Q-Matic drive.

PS. Several have already tested the HF motor with the Q-Matic drive system.

We now return this post to the original concept the "challenge"

Have fun,
 
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tyrslider

New Member
Sep 26, 2008
958
2
0
RainCity
Quenton,

Seems there're a couple substantial parts that you included in the "etc" moniker . e.g. custom exhaust & custom airfilter.

Motor is 89.99 on sale and 109.99 reg price. Which leaves $140-$160 left over to buy a custom sprocket, airfilter, exhaust, and motormount, aftermarket throttle and Tsubaki chain. Good Luck!
 
Hi Evan,

I will gladly include a custom exhaust, motormount, American sourced #41 chain, throttle, rear sprocket, and even a gas tank for $160.00 with the purchase of our $259.75 Q-Matic drive if anyone wants to use the HF motor.

However this post isn't the correct place to solicit or market products, so lets return the post to the original concept "HF Greyhound challenge"

Have fun,
 

tyrslider

New Member
Sep 26, 2008
958
2
0
RainCity
A custom exhaust, custom airfilter, custom motormount, custom 7075 aluminum sprocket, non Chinese #41 chain, better than Chinese kit throttle and a gas tank for $160. That sounds like a good deal! I would think you'll get some takers on that one!
 

MotorbikeMike

Dealer
Dec 29, 2007
477
3
18
Sacramento
Hi Quenton, to my surprise, and great shock, no-one has replied to take up the challenge yet! This is even considering, that I had offered to help them if they got stuck in the process of getting the Blue Elephant running in their bike. I have much in the line of parts and experience, and even tho I am busy, would gladly help.

I still await my competitors, and am looking forward to a nice friendly competition.

Mike
 

kallsop

Member
May 2, 2009
106
1
18
CT US
I have a bike and HF engine and nothing else, and besides, it's a long way from Connecticut to Sacramento! I'm still torn between a good single speed e.g. Q-Matic or a CVT of some variety. The more limited rev range of the HF engine just screams CVT at me, but maybe there's enough torque for a single speed to be good enough.

Hi Quenton, to my surprise, and great shock, no-one has replied to take up the challenge yet!
 
Hi Jay,

If they take Mike up on his offer they can use the Q-Matic and won't need to pedal the HF motor.
As you know several have installed the Q-Matic on the HF motor. And when you and I rode them at Lewes, DE it was clear peddling wasn't necessary.

Mike wants to test the motors if possible on an even playing field, so that only the motors are being compaired.

Have fun,
 
Hi Jay,

Guess not, looks like a lack of confidence in the oversized 79 CC HF motor.

Of course we know why, because we both rode a couple different MB using the HF motors, and therefore we have first hand experience.

I think the HF motor is a good motor, and the price is difficult to ignor, but in stock form it isn't a match against the high reving HS or Honda 49 CC motors.

Main reason is the massive RPM range of the HS & Honda motors vs. the narrow HF RPM range. The HF motor is estimated to work between 1000 and 3600 RPMs [guessed to reach 4500 without governor]. The HF range at best is only 3500, whereas the HS & Honda motors can easily operate between 2000 and 8000 RPMs allowing the massive range of 6000 RPMs. The wider range makes the motor easier to adapt to a MB because it can be geared for easy takeoff and yet allow slightly higher top speeds.

Either motor choice still allow the use of current production Q-Matic drive systems. Mike even agreed to help setup the HF motors for the challenge if needed. He was even willing to have me make special pulleys to change the Q-Matic ratios to fit the HF owners requirements for the challenge.

Oh well! Maybe someone will step up to the plate for a little fun.

Have fun,