Cox Engines Forum
You are not logged in! Please login or register! Guests are limited to posting in the "General Questions (Guest Posting Allowed)" section only. Becoming a member is fast, easy and FREE!


Log in

I forgot my password

Search
 
 

Display results as :
 


Rechercher Advanced Search

Cox Engine of The Month
December-2018
Dave P.'s

"RC Tee Dee 049"



PAST WINNERS
Speed Contest 2018
CEF Traveling Engine

Win This Engine!
The Traveling Prop
Gallery


World of Aviation

My Cox Minibike

Page 2 of 2 Previous  1, 2

Go down

Happy My Cox Mini Motorcycle Frame Design

Post  My Cox Bike on Thu Oct 13, 2016 3:07 am

roddie wrote:I perused quickly thorough this thread this morning before leaving for work. I really love the frame and front-end! Is this being modeled with a particular full-scale bike in mind.. maybe one you've owned or would like to own?

It looks like you have some room to make decisions on the back-end.. to maybe fit your primary-drive on the output-shaft side.. and final-drive on the opposite side.. sort of like a torque-converter/snow-mobile drive. This might help to balance the bike and give you more options with the final-drive ratio. You'd need to prepare the frame for a pair of bearings to support a cross-shaft. I'll bet you've already though about that.

The centrifugal clutch that Cribbs (Ron) spoke of.. would be an item to seek/source. Try searching Cox/Jerobee engine-drive parts on eBay.. and see if you can find anything. One of our members "overlord" (Lieven.. from France) has recent experience with the Jerobee clutch set-up.. and its' associated parts.. dis/re-assembly.. tuning etc. on a scale-model Corvette that he has, with a similar Cox .049 reed-valve engine. I'm sure he will find your project fascinating!

Please keep us up to date with your progress!


I checked out a few generic style frames over the web to get a general idea, nonetheless the frame is my design. I ride a Yamaha mt-03 and it's nothing like that.
At the moment the frame is made from hollow and weak alloy/aluminum tubing, which i will eventually replace when i fine tune the layout, dimensions, and work on my soldering skills with this blow torch. I wanted to keep that look with the top portion of the frame extending to the rear with no extra support. I think with strong material this frame design could be done at 1/1 scale, and if not i don't mind at all. I could just pretend it's a new super metal Wink
avatar
My Cox Bike
Moderate Poster
Moderate Poster

Posts : 18
Join date : 2016-09-13
Age : 31
Location : Sydney, Australia

View user profile

Back to top Go down

Happy Re: My Cox Minibike

Post  My Cox Bike on Thu Oct 13, 2016 4:33 am

roddie wrote:
My Cox Bike wrote:
I need to find or make or find a clutch for this bike! I was hoping to have it controlled as on a real bike, but short on the precision machinery at this point. Maybe a tension system like i think this is, would work?

That "looks like" an idler.. but it's actually a band-brake that actuates when the throttle is closed. It's linked to the throttle-servo and wraps-around a groove in the clutch-bell set-up. Try searching Cox GTP Nissan/Maples throttle.. just to see what comes up. I'm not sure if the "Jerobee" models used the same clutch-system.. but I'd bet on it.

How will your cooling-system work? It looks real good.. with all that plumbing and all.. but what will you use to pump the coolant through it? The boat-modelers use a water-jacket that delivers fresh-cool water around the head, via a pick-up tube placed behind the prop for circulation. The associated plumbing carries the fresh-water in-around the head.. and expels it. A closed-system might not provide enough cooling.

Cox Hobbies used "heat-sink heads" on many of there non-aero powered models to help keep the engine cool. They look similar to the one in the above photo.. except they are totally-flat. You might be able to forego the liquid-system completely.. if it will fit within the bike-frame's perimeter.

Here's a photo of the Cox part#8477 heat-sink, designed for their "Sandblaster" model.. and used on many others.



Mounting-options are a linear 360 degrees around the glow-head. It measures 1-11/16"L x 1-1/16"W..  with the furthest point from the center of the head being 1-1/8".

I think you'll need to find a compromise between an exhaust-throttle sleeve.. and that box-header design that you currently have. An .049 exhaust-throttle sleeve will only fit an .049 cylinder that's been "milled" for it. They're usually obtained in pairs. Boxing the header could still be done.. but the sleeve would need to move within the stationary box. It may be better to keep it simple.. with reliable exhaust-throttle/open-header and air-cooled heat-sink head. You could then concentrate more on the centrifugal-clutch drive.

There are other reed-valve engine throttle-systems.. but they wouldn't lend themselves well to your 90 degree engine-layout for this bike. Those can be discussed when you build a shaft-drive bike!

Hey Roddie,
Thank you and others for the feedback and interest in My Cox Minibike.
Firstly, i'm never getting rid of my cooling system hahaa Wink Enough work went in to hacking a graphics card and that's part of the look, even though there there might be a more practical method. That heat sink might work well on my next model if i get there. I'm hoping to get the coolant flowing through using a similar system they use on RC cars i think - that is having an outlet from the exhaust feeding back into the coolant chamber (which i'm yet to make) and that will hopefully force the coolant through the tubes and cooler head and heat sink at the front. I hope to get that system working, but if not i have a back up plan, which is a tiny electric pump i could fit under the front heat sink. It will inevitably be a closed system, but as with a real bike i'm going to use proper high quality coolant, so there's no over heating, not that that should be a problem anyway. Smile Might start it up for a few to demonstrate my handy work on occasions.

As for all the other very useful info on the exhaust setup and so on, i'll have to get back to that depth with the engine. The clutch might be difficult.



Daniel
avatar
My Cox Bike
Moderate Poster
Moderate Poster

Posts : 18
Join date : 2016-09-13
Age : 31
Location : Sydney, Australia

View user profile

Back to top Go down

Happy Re: My Cox Minibike

Post  KariFS on Thu Oct 13, 2016 7:14 am

Maybe you could make the coolant circulation work with thermosiphon?

http://what-when-how.com/automobile/thermo-syphon-water-cooling-system-automobile/

avatar
KariFS
Diamond Member
Diamond Member

Posts : 1363
Join date : 2014-10-10
Age : 47
Location : Finland

View user profile

Back to top Go down

Happy seat

Post  My Cox Bike on Sat Jun 02, 2018 7:54 am

It has been some time since i've been back here, so, here is the seat.
avatar
My Cox Bike
Moderate Poster
Moderate Poster

Posts : 18
Join date : 2016-09-13
Age : 31
Location : Sydney, Australia

View user profile

Back to top Go down

Happy Re: My Cox Minibike

Post  robot797 on Sat Jun 02, 2018 8:17 am

cool
avatar
robot797
Gold Member
Gold Member

Posts : 338
Join date : 2013-07-28
Age : 28

View user profile

Back to top Go down

Happy Re: My Cox Minibike

Post  getback on Sat Jun 02, 2018 9:12 am

Good to see you back , sometimes people fall off the grid and projects forgotten . Hope things are getting worked out and the seat looks great ! Small Cox Logo
avatar
getback
Top Poster
Top Poster

Posts : 5152
Join date : 2013-01-18
Age : 61
Location : julian

View user profile

Back to top Go down

Happy Re: My Cox Minibike

Post  akjgardner on Sat Jun 02, 2018 8:54 pm

Nice work Dude
avatar
akjgardner
Platinum Member
Platinum Member

Posts : 802
Join date : 2014-12-28
Age : 59
Location : Milan Indiana

View user profile

Back to top Go down

Happy Re: My Cox Minibike

Post  RknRusty on Sat Jun 02, 2018 10:05 pm

Hey, thanks for checking in. We're still here, still interested.
Rusty

_________________
Don't Panic!
...and never Ever think about how good you are at something...
while you're doing it!


My Hot Rock & Blues Playlist
avatar
RknRusty
Moderator

Posts : 10639
Join date : 2011-08-10
Age : 62
Location : South Carolina, USA

View user profile

Back to top Go down

Happy Re: My Cox Minibike

Post  ticomareado on Sun Jun 03, 2018 4:55 pm

So are you going put some outriggers on it and try to run it on a tether? That would be cool. Very nice work.
avatar
ticomareado
Gold Member
Gold Member

Posts : 353
Join date : 2013-10-03
Location : NC

View user profile

Back to top Go down

Happy Re: My Cox Minibike

Post  My Cox Bike on Sun Jun 17, 2018 4:50 am

Cold  Nah... The only way it would be ridden/powered along is, if someone or something small enough could do so. I'll be happy to sit it in my space.
The fork clamp, nearly done.




avatar
My Cox Bike
Moderate Poster
Moderate Poster

Posts : 18
Join date : 2016-09-13
Age : 31
Location : Sydney, Australia

View user profile

Back to top Go down

Happy Re: My Cox Minibike

Post  ticomareado on Sun Jun 17, 2018 6:16 am

What kind of critters do y'all have in the outback that might be trainable to drive your creation?
avatar
ticomareado
Gold Member
Gold Member

Posts : 353
Join date : 2013-10-03
Location : NC

View user profile

Back to top Go down

Happy Re: My Cox Minibike

Post  Oldenginerod on Sun Jun 17, 2018 7:41 am

ticomareado wrote:What kind of critters do y'all have in the outback that might be trainable to drive your creation?

Too small for a Tazzie Devil! lol!
avatar
Oldenginerod
Diamond Member
Diamond Member

Posts : 2277
Join date : 2012-06-15
Age : 56
Location : Victoria, Australia

View user profile

Back to top Go down

Happy Re: My Cox Minibike

Post  Sponsored content


Sponsored content


Back to top Go down

Page 2 of 2 Previous  1, 2

Back to top

- Similar topics

 
Permissions in this forum:
You cannot reply to topics in this forum