Has anyone taken a look at the Briggs and Stratton "Fource" 34cc 4-cycle trimmer engine? I was wondering if it was worthwhile to get one to experiment with.
Charlie

over on the r/c warbird thread , Leo from Spychalla Aircraft , is an engineer at B/S working on new up to date four strokes. he has one of the 34cc ' s on a test bench now with a prop on it.
last weekend at Muncie ,Greg Hahn had a new warbird with one of these four strokes , it flew very nicely ,very scale like , and that is what Greg was looking for. I don't know who had the conversions for them but John out at C and H ignition has been doing the Honda's for some time.
I think matching these engines to the right airframes is the real challenge and to have realistic expectations.
tom

Just as I suspected...I was AT the Scale Masters in Kansas...Saw the 34...Someone said it was a Fuji prototype, made only for airplanes....AHA Same old BS..They think we're mushrooms, keep in the dark, you know the rest
Wait till Tower gets their hands on it.....$$$$$$$$$$$$$ for a Briggs and Stratton....
See the post on RCU gassers....
FWIW..Looked and sounded GREAT on the airplane....[8D]

Did it seem any more or less powerful than the Hondas? Briggs lists it as only having .75 horsepower versus 1.25 for the Honda GX25 and 1.5 for the GX31.
Charlie

Couldn't tell... A 31cc OHC engine would have to be stronger than a 34cc flathead...The strongest flatheads ever were the 750cc Harley flat track engines, and when Honda came along with their modern engines the flatheads went away...I didn't try a 22 6/10 prop on my GX25, maybe Willdo will see this and try it, and MAYBE the people with the Fource 4 on the bipe will post some numbers
As we well know, HP numbers are totally useless for comparing engines and sizes....
I trust Briggs and Stratton on the .75 hp number, and Honda on their numbers...
Maybe TKG already has one ? The ignition on the Fource didn't look like a C&H, could be a Fuji....
Honda GX25...4 1/2 lbs including muffler, battery, and ignition...18-6 Mejzlik, 7500 rpm..

Wasn't sleeping too well (approx 4am) so the computer helps, (better than the garbage on tv)

I happen to have have another prop (wooden) somewhere, might be a 20x6 as well as my "classic plastic" 18x8, so I will try that on the Honda, - it's in the plane, but getting the plane balanced properly, and the throttle arrangement fine tuned, is holding things up.
The weather isn't looking good for this weekend, so that'll help me to save face!

BTW, - Does BS mean bulls**t or Briggs & Stratton ?

Are you serious about B&S still desiging flatheads?

I'm not a motorcycle nut but I though Harley went to OHC in the 30's. I could be wrong but I don't think B&S makes a flat head these days. If you are saying that Honda started with OHC lawnmowers. Then you should know that my lawnmower is a flathead Honda HR-21 I bought in 1982. Darn thing won't quit.

Harleys changed to OHV ( as opposed to OHC), in the sixties, ( must've been about the last company to do so).

WAY Earlier than that..Think Harley Knucklehead, 1936..

Well, I sure got that one wrong! - I should do my homework before typing!

There are about 1.1 million Briggs & Stratton flat heads being made every year. We call them "L" Heads. Just take a trip to your local Home Depot or Walmart and that is most of what you will see on the low cost mowers. The market is changing slowly over to OHC and OHV configurations for the sake of emissions, but it will take time.

I got my B&S Micro for free. I have not had much time to mess with this 34cc 4-stroke. Mounted a prop to it and bench ran it. I am not sure if it holds any promise for a flying machine or not at this time. I have seen Greg Hagn fly his FUJI 4-stroke 1/2 dozen times. I think he has some issues to work out regarding starting and power. Regardless of those issues, it sure does sound nice.

One nice thing about the B&S versus the FUJI is that we have a full 360 degree wet sump. Greg's engine can only run upright if I am not mistaken.

Here is a picture of the Briggs. It's mine and I have no plan to get anyone one of these until I can finish an evaluation for myself.

Leo

Looks like I ASSumed again....Fuji and Fource are not the same....Sorry for the misinformation.....[&o]
BTW..Leo's Spitfire was one of the best flying planes at the Scale Masters, and he was way up there in flight scores.....
Still can't see Fuji making a small four stroke just for a limited market like model airplanes..Gotta be some other application...[8D] Time will tell.....

Robin engines uses Fuji in weedwacker.

I looked all over the internet last night, saw the Fuji site, looked like a 25cc was the only 4 stroke listed.....

http://www.robinamerica.com/engines/...asso?mdl=EH035
This might be the one. Took me a while to find it again

Thought I'd clarify a few things on the Fuji 4 strokes. I've been working with great planes and Fuji on this project for a few months now and things are going well and on sched. The 34cc and 25cc engines are slated to arrive mid to late Dec. I've been working on the operation perameters and have found they develop great power and torque. I have been running the 34 with a 22 x 6/10 prop on my fokker D VII and the rpm doesn't lag in a good loop. I also like a 20 x 10 and 20 x 12 for this engine.
to answer leo's line about inverted running, both of the Fuji engines can be run inverted for at least one minute with out loosing power or damage. As with the briggs, these engines also have a 360 degree sump. These engines are ohv with a gear driven cam and I can get almost an hour of run time out of 16 oz. of gas
To answer the other question, I was informed that these engines were made for airplanes. They power target drones for the Japanese military
These engines are ultra quiet and the sound you do get is so right it's hard to believe!!!
the starting problem I experienced earlier was due to an old fouled plug. Starting is very easy otherwise. The only thing that takes some getting used to is letting it warm up after starting. The oil needs to get warm before rolling out to the runway
hope this helps, I'll check back from time to time

[quote]ORIGINAL: a walk in the park

Thought I'd clarify a few things on the Fuji 4 strokes. I've been working with great planes and Fuji on this project for a few months now and things are going well and on sched. The 34cc and 25cc engines are slated to arrive mid to late Dec. I've been working on the operation perameters and have found they develop great power and torque. I have been running the 34 with a 22 x 6/10 prop on my fokker D VII and the rpm doesn't lag in a good loop. I also like a 20 x 10 and 20 x 12 for this engine.
to answer leo's line about inverted running, both of the Fuji engines can be run inverted for at least one minute with out loosing power or damage. As with the briggs, these engines also have a 360 degree sump. These engines are ohv with a gear driven cam and I can get almost an hour of run time out of 16 oz. of gas
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[sm=confused.gif] Leo, does this mean the Briggs can be mounted inverted??


Barry

Say "A walk in the park", which Fokker D V11? Weight and wing span?

Thanks,
AV8TOR

Gismo,

Once again I will preface my comments on the Briggs & Stratton Micro to say that I have not had time to work on it. I am in the midst of making and shipping fifteen 1/5th scale Wildcat Fuselages for a new product I introduced. It will keep me busy till mid December 04. Regarding the Micro. The development engineer on this program has run the micro inverted for over 24 hours as part of his test program. His commentary to me is that it ran just fine and had no degradation to the engine. I do believe oil consumption was slightly up. Much of this performance is attributable to its two chamber oil sump. Now for a model application I think testing is the only answer to prove it will work inverted. I have a Balsa USA DR1 and given some time I plan to try it out. Maybe I could fly formation with Greg Walk-In-the-Park's DVII next summer. This would be fun and I hope to be the guy to do it. If somebody beats me to it... power to them.

Leo Spychalla
(Day Job) Briggs & Stratton Program Manager - Ride Group

Leo, one question. Is there any way to get one of these engines without downloading one from a string trimmer? I e-mailed Briggs and Stratton asking how I could buy one because I didn't see the engine listed for sale with any dealer, and they sent me back a terse e-mail stating that "The Fource engine is not for sale to the general public." [:@] Sounds pretty silly to me to advertise a product that is impossible to buy.
Charlie

Honda did come out with many OHC engines .....Continental Motors in Musk Mich, built OHC tank engines before Honda invaded us with Motorcycles with OHC engines. The unicyliner with cylinder head (all one piece) , was also made by Continental before Saito did it. The 1790 cubic inch air cooled tank engine is qutie a masterpiece of work.

Charlie,

Briggs deals in thousands. An order for 2,000 engines comming from an OEM might get their attention, but not much less. So for right now I think your best bet is to buy a string trimmer and cut it apart. Long-term, when I get some time and determine if this engine is worthy of model aircraft use I may develop a channel to the R/C market. Prior to that I do not intend to supply any modelers.

I am surprised that the dealers cannot lay their hands on one as a replacement part. I think your just not talking to the right guys.

Leo

Leo, I would like to compliment you on your work, I have a TroyBilt, tiller, mower and 6,500 watt generator, all equipped with B&S engines, the 5HP tiller is a flathead, the mower a 6.5HP OHV and the Generator a 9HP slanted OHV that the specs say is all roller and ball bearings. High quality and easy starters all. Keep us posted on the evaluation.

I spent about 1/2 hour on the phone this morning trying to find a B&S Fource 4 trimmer in the Phoenix, AZ area...Apparently a city of over 1,000,000 people with a gazillion yard services is not large enough to have a dealer that will handle the Fource 4...Good luck finding one...
There are many B&S dealers listed, just none that have a Fource 4...Must be a big seller
Sarcasm INTENDED

I was looking on the web and found a trimmer for $170.00 with the Fource motor. I haven't tried to buy one from these guys yet, hopefully they sell to the public. Here is the link. http://www.outdoordistributors.com/w..._trimmers.html

Good luck and let us know if you score one.

Cheers,

Barry