79cc HF engine "deal" or hype ?

[andyszyd]

Reading all post about this engine I was about to get one, but then I cooled off.

Pros:

1. You can't beat the price (below $100 for 2.5HP engine).

2. 2.5HP and good torque.

Cons:

1. Difficult frame mount fit on most bikes.

2. Too heavy for rack mount.

3. Not powerfull enough for a "pusher".

4. Only about .4 or .5 HP more than Honda/Titan/HF52cc 2 stroke at 10-14lb more weight (80-120% more WEIGHT).

2. Weight 22lb 10lb more than Titan, Honda 50 at .4 HP gain, 14lb more than HP 52cc 2 stroke at 2HP+? .4 gain at 14+weight.

3. How it is a Honda 50 "killer" with only 0.4HP more (19%) and 10LB + (54% more) ???

3. Can you really take adventage of its torque without a kind of
shift kit or CVT?

How do you propell the bike to get it to the "new speed record" using all 1speed (3rd gear only) most popular setups?

I do not want to peddle heavy engine + bike + my weight to 10 MPH or more to reach "new speed record for $79.00 " sorry.


THIS IS NOT TO KNOCK OFF ANYBODY WHO IS HAVING FUN WITH THIS ENGINE !!!

I just can not justify to buy it only cause it is a "bargain" since I can not see an advantage to use it for MB in comparison to other engine options available.

 

[Quenton Guenther]

Hi Andyszyd,

The biggest advantage to using the HF motor would be as a replacement for a blown 2 stroke motor because many of the kit parts can still be used [gas tank, throttle, rear sprocket, chain tensioner, etc]. The HF motor would only need a motor mount & drive system to make it workable.

I agree with you about size, weight, and the slight difference in torque, and you are also 100% correct about the "Honda Killer status".

We have tested the Q-Matic [dealers conducted the tests] with the HF motor and decided to produce our drive to "bolt-on" the motor if anyone wants to give it a try [must request the drive to fit the HF motor when ordering].

We are able to set the Q-Matic clutch system and ratios to make it work with the HF motor.

Have fun,

 

[stealthc9]

well, @ how many rpm's are the honda, and titan motors making that power?? The HF engine is makin the claimed power at it's Governed rpm. Disable the governor and you will have more power. Now I dont know how high these engines can rev. But I am willing to give it a shot...

 

[andyszyd]

"Blown 2 stroke motor" ?

I think you mean 2 stroke HT motors, not 2 stroke quality motors like Mitsu and Tanakas.

They very rarely "blow" unless you feed them pure gasoline.

In case of HT motors you've got it right.

Still HF 79cc engine at 22lb + weight of one speed 3rd gear only kit + 45lb bike does not rock my boat.

 

[andyszyd]

well, @ how many rpm's are the honda, and titan motors making that power?? The HF engine is makin the claimed power at it's Governed rpm. Disable the governor and you will have more power. Now I dont know how high these engines can rev. But I am willing to give it a shot...

Nothing wrong with that, you can hopefully get safe 4800 RPM out of it, but you still need something better than 1 speed set up to take advantage of increased power band and torque of this engine and to offset its weight.

 

[stealthc9]

Well, I dont want a speed machine. Im putting it on my Schwinn OCC Stingray, So Im not concerned with the weight. Or the Speed, Like if I can get my bike to do 45mph i'll be happy. (then I can keep up with traffic)

 

[arceeguy]

Don't look at just HP.

The HFT 79cc has torque, and needs to be geared accordingly. Disable the governor, the low oil switch and keep it under 5K RPM's. I would estimate gearing maximum sustained cruising speed for around 4000 RPM's. In a little mini-bike, the 2.5 can cruise at 40, yet have decent acceleration due to its low end torque. (with no gears) Gear a 50cc two stroke to do 40 and you won't ave enough torque to pull a lollipop out of a baby's mouth. (in other words, get ready to pedal!)

40 on a doodlebug minibike is even more scary than 40 on a bicycle. Talk about "squirrely" handling!

 

[stealthc9]

If I was doing direct drive what sprockets should I use? 11tooth front with how many rear?? on a 20" schwinn chopper with the 20"x4" tire I would like to cruise at 45mph

 

[Happy Valley]

Weight 22lb

Loses me right there, add the drive components and for me it's out of the realm of MAB and into another category.

Nevertheless, it'll be interesting to see how reliable these engines will be over time and how they hold up with actual accumulated mileage. I well remember back a few years when the HT engines were becoming popular and the early enthusiasm for them.

 

[Youngbird]

Not gonna happen, Stealth. You cant use a single gearing to do what you want to do. You need gearing or another drive setup. Look into MaxTorque convertors(drive and driven) then we'll talk some more. Or better yet....go toEZM and check out the Q-Matic Silent drive. Good luck.