Brison 4.8 ci/78 cc Twin Gas - RCCanada - Canada Radio Controlled Hobby Forum
RCCanada - Canada's Radio Control Hobby Forum
Large Engines Discuss Engines Used on Giant Scale Aircraft. Gas/Glow, as long as they're big!

Thread Tools Display Modes
Old 07-03-2012, 05:55 PM   #1
RCC Senior Contributor
Cricklewood's Avatar
I am: Chris K.
Join Date: Aug 2006
Location: Caledon, Ontario

Feedback: 21 / 100%
Posts: 684
Total Props: 3
Brison 4.8 ci/78 cc Twin Gas

       Remove this ad - become a site supporter!
I recently acquired a used Brison 4.8 ci/78 cc twin gas engine which I am trying to get more information on. The engine has an electronic ignition with a mechanical advance for the timing.

The engine starts quite easily but seems to be skipping on one cylinder at low speeds, there is noticeable exhaust smoke when it skips, until it warms up. After warming up it seems better but is still a bit rough.

The skipping was also an issue when I throttled up. After playing with a few things I adjusted the mechanical timing advance arms, shortened then a few turns, which seems to have improved the situation.

A few of questions that I have are:

1) Are there any suggestions on how to improve the situation with the cyclinder skipping at low speeds?

2) Does anyone know what sort of performance, rpm, one can expect to get from the engine? I currently get about 6190 rpm using a 24 x 10 prop and am not sure if that is in the expected range.

3) What spark plugs would normally be suggested for the engine? How much of an effect would different plugs have on the performance? The current plugs are Champion RDJ7J's.

Any help would be appreciated.

Thanks, Chris
Cricklewood is offline   Quick reply to this message.

Sponsored Links - Subscribe to remove this ad.
Old 07-04-2012, 07:17 AM   #2
Dale Hunter
RCC Supreme Contributor
Dale Hunter's Avatar
I am: Dale Hunter
Join Date: Jan 2009
Location: Camrose, Alberta
Radio of choice:
a 12 X in each hand !

Feedback: 23 / 100%
Posts: 8,586
Total Props: 39
Re: Brison 4.8 ci/78 cc Twin Gas

Chris, I beleive the cylinders are Husqvarna 2.4cid (Brison often used Husqvarna).
My First Place 2.4 (Husky jugs) uses RDJ8J plugs. Fresh plugs is where I would start.
I too have a ZDZ 80 twin that shows a lazy cylinder cold, but after it catches and warms up is solid. I would suggest if your intermittent cylinder dosn't clear up when warm, avoid flying it. It wont get better in the air.
Hope this helps, -Dale-
FishFly - FunFly, Sept 11-13. Great fun!
Trout Farm Flyers. Life is good.
Dale Hunter is offline   Quick reply to this message.

Quick Reply

Register Now

In order to be able to post messages on the RCCanada - Canada Radio Controlled Hobby Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

Member names may only be composed of alpha-numeric characters. (A-Z and 0-9)

!!ATTENTION ADVERTISERS!! If you intend on advertising anything on this forum, whatsoever, you are required to first contact us here . Additionally, we do NOT allow BUSINESS NAMES unless you are an Authorized Vendor. If you own a business, and want to do sales on this site via posting or private message, you will need to follow the rules. Shops, Stores, Distributors, Group Buys without being authorized will see your account terminated.
User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Your Name
Your first name and last initial is required if you plan on using the forum.
Which city & province you live in. This is mandatory for classified listings.
Radio of choice?
Which radio is your current favorite to use?
Number of RC Vehicles?
How many boats, cars, planes do you own?


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
vBulletin Message

Thread Tools
Display Modes

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Brison 4.8ci/78 CC Twin Questions Cricklewood Engines 0 07-03-2012 01:41 PM
50 CC airframe for 30 CC gas plane jalot2000 Trades Only 0 04-06-2011 10:57 PM
45 to 50 cc gas twin pipercub17 Wanted - Engines 0 09-25-2010 07:17 PM
LARGE 282 CC Gas Twin Engine For Sale 50%300SFlyer FS - Engines 8 05-27-2009 10:49 AM
Wanted (1.8-2.3 ci)(26-38cc) gas engine " Got one" cf-drg Wanted - Engines 2 12-22-2005 01:16 PM

All times are GMT -5. The time now is 07:14 PM.

vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2016 DragonByte Technologies Ltd.