The HF Greyhound Challenge

GoldenMotor.com

jbcruisin

Active Member
Oct 10, 2008
1,118
7
38
Lebanon, Pa.
Still no challengers for Mike?? I guess this proves that the Hueshang engine & the EZ drive rules!! Sounds like the race is won by default. No challengers.
Jay
 

MotorbikeMike

Dealer
Dec 29, 2007
477
3
18
Sacramento
Hi gang, well! Now that they are making a thread about the HF build-off maybe someone on the Central West Coast, North CA, or Northern Nevada, is gathering steam to take up the challenge? I am still completely without a challenger after having completed a VERY COLD 95 mile MotorBike run with the gang of West Cast Whizzers!

This ride had up to 15 mph winds, and my leather jacket was hanging peacefully in the closet at home! I had the feeling of icicles thru my hooded sweatshirt, right thru my t-shirt at 25 mph with 15 mph 55 decree wet headwind! The wind chill was heartfelt! I was constantly depressed at the thought of 2 pair of my leather riding gloves back at camp in the Chevy, while I am white-knuckling thru the spring storm!

I will now admit, that due to my work schedule, my personal schedule both working on EZM stuff, and family obligations I had NOT done any prep on my bike! YES it had basically sat thru a nasty wet winter, and was dragged out on a cold day facing 90-100 miles on the road running with the larger displacement Whizzers.

Come on guys, I will give you these advantages......the Superior ???? HF engine, with its larger (not legal here but I don't care), it's higher HP rating (again not legal in CA. but who is counting?), and I am a heavy rider, which you may not be?

Bring on that wide-bodied, over displacement, over HP Harbor Freight Train! I should be ready, rust and all!

Mike

Bring on your low cost HF's and lets rumble? As the spring wears on into summer, I will build the new bike to hold my little GX50,
 

Elmo

New Member
Sep 3, 2009
748
4
0
Mississippi
My HF was $76 + tax no shipping. I have enough love for all the bicycle engines.
I gave 32.84 at Dirt Cheap for the last one that I bought. Had a dent in the in the pull start housing that had it locked up, pounded it out and it runs like a charm. the one before that cost 42.85 and needed a sparkplug.
BTW my hf 2.5 hit 37 mph on flat ground with a 26 inch wheel and 12 to one reduction and it did not blow up.
 
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Elmo

New Member
Sep 3, 2009
748
4
0
Mississippi
I usually give it about 2 turns on the pedals to save wear on my clutch but it will pull off nicely without pedalling.
 

Gator Wrestler

New Member
Jan 22, 2009
124
0
0
Springfield LA
A well broken in HF 2.5 has been clocked at 40MPH . Elmo, your engines will get a bit faster after they loosen a bit. I am using 12 to 1 after trying 8.8 to 1 and 10 to 1 wqith a 20" wheel. I would like to build one with a torque converter.

Tom
 

4950cycle

New Member
Sep 8, 2010
111
1
0
Dunnellon,FL.
I wish we would post rider weight when publishing top speeds accomplished by whatever drivetrane you choose. A 110 lbs. rider is a horse of a different color from a 200 + lbs. rider when it comes to compareing performance on anything that moves. Not to mention the wind resistance of the larger rider. I'd be willing to give the wind resistance away to have a level comparison considering weight of rider. Thank you for listening.cvlt1
 

MikeJ

New Member
May 3, 2009
82
0
0
Colorado Springs
Hi Elmo -

It has been a long time since I logged into this forum. Your latest post is especially interesting to me. I spent the past six months or so putting together an extra long bike (no deadline to meet; no hurry to finish; just build smartly). See by my photographs (if successfully attached) that my bike is not even close to run-of-the-mill. The photos depict my bike as of today. Some additions (tail light, basket, etc.) are pending.

Observation: My bike weighs in at close to 100 pounds. It's going to weigh as much as a Harley Electraglide pretty soon! And then I am weighing in at 200+ pounds. I hope those wheel bearings can take such a heavy load!

I have to work out the "pulsing" I feel in the low-2000 rpm range as I accelerate away. I attribute that "pulsing" to the long drive chain bouncing between the bottom bracket cog and the rear Sick Bike Parts MegaRange 34-tooth sprocket. (My final gear ratio with this MegaRange gear is about 14.1:1.) Unless that rear wheel is tightly in place, that "pulsing" will yank the gears forward out of the rear dropouts. Then the wheel jams and I grind to a quick halt. This is not good in traffic. But I am testing in an empty parking lot for the next few days. I think I know how to get that chain bouncing under control.

Did you have a similar problem? And if so, how did you fix it?

Like you, I pedal up to about 8 mph before I throttle up to engage the centrifugal clutch. My jackshaft is home designed, but it works rather well. I have no complaints with it. I know the multiple gears of the rear wheel cassette can handle the load.

The HF 79cc engine pulls me along as well as can be expected, given my weight, the altitude (over 5000 feet above sea level here) and the fact that the engine is only 79cc. It and I will not break any speed records; I am not a speed demon. (First gear: 19 mph at 3500 rpm.)

I have only 10 miles on the engine right now, but once I get that chain bounce controlled and some tail lights wired up, I am going to start venturing further from home base (with motorcycle helmet, bright yellow jacket, selected tools, spare inner tubes, etc).

I have ambitions to complete at least one 200-mile round trip this summer. Once I get the chain problem fixed, there is no reason why this engine and build will not complete similar trip several times over, and still run good as new at the end of the warm-weather season.

If you can post some photos of your build (or tell me where to find them), I would like to see what you are riding.

Thanks,
MikeJ
 

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Elmo

New Member
Sep 3, 2009
748
4
0
Mississippi
I would suspect that your surging is coming from your rear derailleur with the chain take up moving forward then catching up again. I do not know the fix, maybe a stronger spring if that is what is causing the problem. Get some to watch and maybe see if this is the problem. I did not have any problems but I used a single speed setup. My build is sort of similar to yours and is here. http://motorbicycling.com/f36/finishing-greyhound-build-12738.html
My longest ride was 130 miles or so round trip.
 

MikeJ

New Member
May 3, 2009
82
0
0
Colorado Springs
Hi Elmo, Everybody -

I solved my problem. Recall my bike's long drive chain was "bouncing", causing my bike to "pulse" forward. I figured that if I could stop the bouncing, the pulsing would stop. Here is my fix:

Went to Ace Hardware (spent LOTS of money there). I purchased a length of their large diameter plastic (silicon?) tube. See photos. I also purchased a 5/8 inch solid shaft, eight inches long. They had 5/8 inch diameter bolts for less than $3 each (Great! No cutting involved!). I already had the inexpensive Ace roller bearings of 5/8 inch internal diameter, which just happen to fit perfectly inside the plastic tube! Nice fit! The shaft rested nicely in the frame valley, the 2 inch length of tube rotated without friction, the chain rested on top of the relatively soft plastic, and placed a very slight apex angle in the chain when it was under tension. I fastened it all down with intent to make it easy to remove if necessary. So visually, it is not real pretty. But it works! (You may need to rotate the second photo; I had to upload it as you see it.)

During an 8-mile test ride late today, the chain rode over this "chain idler". The idler rotated at chain speed, and made not a sound whatsoever. And accelerate as hard as I tried, there was no chain bounce! Hooray! Another engineering problem solved! With readily available parts!

Now about that 79 cc HF engine... In the 2000 to 2400 rpm range, that little engine likes to produce some serious torque pulses during its power stroke. Given the length of my bike frame and its inherent flexing, my bike does quite a bit of shaking until the engine gets over 2400 rpm. Then the bike settles down and rides as expected. I noted some other unexpected additional random shaking. Then I realized that was from the imperfect road surface.

At my altitude (currently in Albuquerque) of 5500 feet, I look up derating an engine because of high altitude. At full throttle, gasoline engines are derated. One chart I found derated at 3 percent for every 1,000 feet above sea level. So I am at a slight disadvantage compared to sea-level bikes in all-out acceleration and wide-open throttle top end.

I added a cargo basket and some rear attention-getting lights. The brake light is wired to go full bright when I squeeze the rear brake handle; it is an LED truck light powered by a 12 volt sealed acid battery. The strobe flasher (from Radio Shack about 16 years ago) is a real attention getter in the dark. I safety-wired it down so it will not break loose if I hit a nasty pothole. Now I just need some headlights, red reflectors, and the air horn that I already have. Then I am ready for night riding!

The bike is in its break-in phase right now. It has only 18 miles on it. Nothing has broken (yet). It need more stress testing. In a couple of weeks, I may take it to the east to a town about 30 miles from here. There is a 7,000 foot pass between here and there. I think the bike and I will make it if I don't overrev the engine.

That is my long-winded story. I will probably have more to write in the future....

MikeJ
 

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LS614

Active Member
Dec 22, 2009
1,236
3
38
CT and MA
Hi guys, I guess I'm the first person who does not YET have an HF build to take on this challenge :D I'm getting the Q-matic and mounting plate from JB and an HF engine for somewhere around $96. I'll keep you posted on how this goes :D Does the mounting plate not fit the HF engines in its stock configuration? How much modding would it take? Wish me luck :)
 
Hi LS614,

The HF motor has to mount to the right side [sitting on bike]. None of the mounting plates are drilled, or wide enough to match the correct location for the HF motor. A simple metal plate can be attaced to the majority of available motor mounts, and will make the project much easier. You can use the parts in the motor mount as the basis to attach the platform to the frame, and fabricate a plate to attach the the basic mount.

We will gladly help you adapt the motor to work, and will even fine tune the Q-Matic ratios to work better with the HF motor [we have some experience, as many have made this conversion].

Have fun,
 

LS614

Active Member
Dec 22, 2009
1,236
3
38
CT and MA
Thanks! It's good to get advice from the man who's the Q behind Q-matic :D I'll definitely figure it out! This will be such a fun build! :)