HOME  |  NEWS  |  BLOGS  |  MESSAGES  |  FEATURES  |  VIDEOS  |  WEBINARS  |  RESOURCE CENTER  |  INDUSTRIES
REGISTER   |   LOGIN   |   HELP
sbkenn
User Rank
Gold
Re: Must Have Been A 2-Stroke!
sbkenn   7/23/2011 10:17:29 AM
NO RATINGS
On the old Guinness canal boats, used to transport the famous beverage bearing the company name, the skippers could reverse the Bollinder single cylinder diesels by closing the throttle(though throttle isn't really the right term), until the engine was almost stopped, then "blipping" the throttle at the right moment.  These engines only had a forward gear, and would run their bearings dry if left running backwards for long.

wb8nbs
User Rank
Silver
Re: Must Have Been A 2-Stroke!
wb8nbs   7/22/2011 5:04:30 PM
NO RATINGS
Four stroke diesels wil run backwards too.  It surprises the heck out of the driver and blows all the oil out of the air cleaner. DAMHIKT.

arrowpal
User Rank
Iron
Re: Must Have Been A 2-Stroke!
arrowpal   7/22/2011 1:43:00 PM
NO RATINGS
I agree, a 2-stroke. Very common issue, especially in the early days. A 2-stroke engine will run either direction. Improperly adjusted ignition timing can aggravate the reversing problem.

wayneowatts
User Rank
Iron
Re: Must Have Been A 2-Stroke!
wayneowatts   7/22/2011 1:35:06 PM
NO RATINGS
My thoughts exactly.  As a youngster in the 70's I was involved with racing small 2-stroke motorcycles and heard several stories about them suddenly going in reverse from the starting line.

 

VM
User Rank
Iron
Re: Must Have Been A 2-Stroke!
VM   7/22/2011 1:30:31 PM
NO RATINGS
I'm sure it was a 2 stroke...

Many Years ago (more than I care to think about)  A friend of mine was tweeking the ignition timing on his suzuki 250.  Advanced it a little bit, started it, cracked the throttle and dropped the clutch.  Did this a number of time - happy with the perceived increase in acceleration until he just went a little too far.

He started the bike (kick start of course) and received a nasty kick back to boot.  The bike was running through, so he goosed the throttle and dropped the clutch.  The next moment he was lying on the ground,hands cupped around a fragile and now very painful part of his anatomy.

The engine had started in reverse - need I explain further....

PhilR
User Rank
Iron
Backwards.
PhilR   7/22/2011 1:27:39 PM
NO RATINGS
It is entirely possible you are putting us on.  However...

Reed valve 2-cycle gas engines can run backwards and forwards, depending on the spark timing. Very small Cox Model airplane engines, for instance, run equally well in either direction and it's not un-common for them to start backwards as they come up on compression, bounce back without going over TDC (top dead center), and then fire and run in reverse.

I guess that you almost stalled the engine starting out, the piston didn't quite make it past TDC, and the plug fired just about the time the piston stopped.  The piston was then pushed down and the engine began running backwards, with a delayed spark being the only symptom.  You were probably too busy to notice the lack of power.

Cheers.

ntglover
User Rank
Iron
Was it a 2-cycle engine?
ntglover   7/22/2011 1:25:02 PM
NO RATINGS
I suspect your little 50 cc engine was a 2-cycle engine.  If for some reason the cranckshaft began rotating in the reverse direction - perhaps because of a near-stall on acceleration or a kickback from early ignition - you would have everything reversed.  Bingo - your one-speed forward would become a one-speed reverse. 

Plexus
User Rank
Iron
Must Have Been A 2-Stroke!
Plexus   7/22/2011 1:19:22 PM
NO RATINGS
The old two-stroke switch!  Some economy 2-stroke engine designs would reverse direction when seeing a throttle demand from an idle condition.



Partner Zone
Latest Analysis
We see Gadget Freak projects from all walks of life, but many of our most imaginative gadgets are created by budding engineers.
By experimenting with the photovoltaic reaction in solar cells, researchers at MIT have made a breakthrough in energy efficiency that significantly pushes the boundaries of current commercial cells on the market.
Advanced Micro Devices' latest release brings a cloud-based graphics boost, along with unparalleled performance, to the workstation.
In a world that's going green, industrial operations have a problem: Their processes involve materials that are potentially toxic, flammable, corrosive, or reactive. If improperly managed, this can precipitate dangerous health and environmental consequences.
With LEDs dropping in price virtually every year, automakers have begun employing them, not only on luxury vehicles, but on entry-level models, as well.
More:Blogs|News
Design News Webinar Series
5/22/2013 9:00 a.m. California / 12:00 p.m. New York / 5:00 p.m. London
5/15/2013 11:00 a.m. California / 2:00 p.m. New York / 7:00 p.m. London
5/29/2013 11:00 a.m. California / 2:00 p.m. New York / 7:00 p.m. London
5/30/2013 11:00 a.m. California / 2:00 p.m. New York / 7:00 p.m. London
Blogs from Our Sponsors
From Dell / Intel®
New Paradigms in Design Work
Scott Hamilton, vertical market strategist for Dell Precision workstations, 5/2/2013    3
Early in my career, I worked as a draftsman and remember the days of drawing on vellum with numbered pencils and Mylar with plastic lead. This was a fun experience in the sense that I ...
From Dell / Intel®
Increased Workstation Performance Is as Easy as 'DPPO'
Trey Morton, Dell, 4/25/2013    2
I've been using workstations for more than 10 years and love finding ways to get more performance from my system. With demanding professional applications that require more power each ...
From Dell / Intel®
Taking Some of the Grit out of Manufacturing
Kirsten Billhardt, Manufacturing Industry Marketing Strategist, Dell, 3/26/2013    5
A lasting memory from my first job as an engineer in an auto assembly plant is standing on hard concrete at six in the morning, vending-machine coffee clutched in hand, listening to ...
Quick Poll
The Continuing Education Center offers engineers an entirely new way to get the education they need to formulate next-generation solutions.
Jun 10 - 14, Exploring Application-Specific Programmable Logic Devices
SEMESTERS: 1  |  2  |  3


DN Radio
Sponsored by
NEXT UPCOMING BROADCAST
A quick look into the merger of two powerhouse 3D printing OEMs and the new leader in rapid prototyping solutions, Stratasys. The industrial revolution is now led by 3D printing and engineers are given the opportunity to fully maximize their design capabilities, reduce their time-to-market and functionally test prototypes cheaper, faster and easier. Bruce Bradshaw, Director of Marketing in North America, will explore the large product offering and variety of materials that will help CAD designers articulate their product design with actual, physical prototypes. This broadcast will dive deep into technical information including application specific stories from real world customers and their experiences with 3D printing. 3D Printing is
Twitter Feed
Design News Twitter Feed
Like Us on Facebook

Sponsored Content

Technology Marketplace

Datasheets.com Parts Search

185 million searchable parts
(please enter a part number or hit search to begin)
Copyright © 2013 UBM Canon, A UBM company, All rights reserved. Privacy Policy | Terms of Service