Page 2 of 2 FirstFirst 12
Results 16 to 24 of 24

Thread: hcci test

  1. #16
    Join Date
    30th April 2011 - 04:57
    Bike
    bsa. honda. aprilia
    Location
    england
    Posts
    390

    you tube

    I've tried to add you tube video... but I give up...its on there ...nitro/petrol mix with igniter

  2. #17
    Join Date
    30th April 2011 - 04:57
    Bike
    bsa. honda. aprilia
    Location
    england
    Posts
    390
    i


    Sort of fires but my fuel delivery system is crap !! It also doesn't want to know at all without the igniter battery..

  3. #18
    Join Date
    7th September 2011 - 00:26
    Bike
    bsa bantam
    Location
    england
    Posts
    49
    Hi Nigel,
    Great to see that you are still doing crazy, innovative and inspiring stuff, hope you get there mate, can`t wait for a new `Midlands`, perhaps next year.

    Regards, Trevor

  4. #19
    Join Date
    30th April 2011 - 04:57
    Bike
    bsa. honda. aprilia
    Location
    england
    Posts
    390

    Sealing issues

    Well this is my design for my adjustable combustion head which is a rehash of the one i made earlier. It wouldnt seal ... If anyone has any advise on what i intend to do please comment.so Maybe it wouldn't be another wasted effort..Click image for larger version. 

Name:	20201014_170653.jpg 
Views:	81 
Size:	726.1 KB 
ID:	347496

  5. #20
    Join Date
    28th August 2015 - 00:01
    Bike
    1975 Hodaka Wombat
    Location
    Eugene, Oregon, USA
    Posts
    302
    We did some testing with a 26 cc racing engine on glow ignition. We couldn't get the plugs to hold up. The plugs that could stand the pressure wouldn't constantly fire and the others blew out the center element. We probably needed to play with head volumes. On spark ignition it ran well on 15% nitro model fuel, but burned the electrodes off the plug on 40% nitro. I wrote an article on model engine head design. See namba.com/content/library/propwash/2019/october/4/#zoom=z if that helps.

    Model "diesels" depend on a close fit with the moveable head and the cylinder. They're adjusted by a central screw. I'm not sure how well that would work on a larger bore. Our luck with this style piston on a 36 cc engine wasn't good. The head is a less exacting application, though. It needs to be very close to a zero clearance fit in a very round bore.

    Lohring Miller

  6. #21
    Join Date
    30th April 2011 - 04:57
    Bike
    bsa. honda. aprilia
    Location
    england
    Posts
    390

    sealing...

    Quote Originally Posted by lohring View Post
    We did some testing with a 26 cc racing engine on glow ignition. We couldn't get the plugs to hold up. The plugs that could stand the pressure wouldn't constantly fire and the others blew out the center element. We probably needed to play with head volumes. On spark ignition it ran well on 15% nitro model fuel, but burned the electrodes off the plug on 40% nitro. I wrote an article on model engine head design. See namba.com/content/library/propwash/2019/october/4/#zoom=z if that helps.

    Model "diesels" depend on a close fit with the moveable head and the cylinder. They're adjusted by a central screw. I'm not sure how well that would work on a larger bore. Our luck with this style piston on a 36 cc engine wasn't good. The head is a less exacting application, though. It needs to be very close to a zero clearance fit in a very round bore.

    Lohring Miller
    thanks, ill take a look at the article.. i had hoped my original piston ring sealing method would be the way to go and maybe i should have another go at it but improve my machining... or even try and press in a pre plated sleeve with an opposing modified piston. at least that wouldn't need me to up my game on the machining front.

  7. #22
    Join Date
    30th April 2011 - 04:57
    Bike
    bsa. honda. aprilia
    Location
    england
    Posts
    390

    latest

    tried the threaded piston ..... but still no satisfactory seal,,

    Click image for larger version. 

Name:	kiwi2.jpg 
Views:	36 
Size:	690.0 KB 
ID:	348642Click image for larger version. 

Name:	kiwi3.jpg 
Views:	36 
Size:	713.8 KB 
ID:	348643Click image for larger version. 

Name:	kiwi biker pic 1.jpg 
Views:	38 
Size:	692.5 KB 
ID:	348644Click image for larger version. 

Name:	kiwi5.jpg 
Views:	39 
Size:	715.6 KB 
ID:	348645


    so Ive made a sleeve from a weed whacker cylinder and pressed that in and machined the piston down and coupled it to a shaft... my starter motor has burnt out so testing this is on hold till i can replace it..
    Last edited by breezy; 4th March 2021 at 06:29. Reason: attachment didint load

  8. #23
    Join Date
    30th April 2011 - 04:57
    Bike
    bsa. honda. aprilia
    Location
    england
    Posts
    390

    threaded piston

    Click image for larger version. 

Name:	kiwi4.jpg 
Views:	67 
Size:	700.7 KB 
ID:	348646 piston threaded, managed to groove the internal shaft to incorporate wire for a glow plug, which was then sleeved with chrome plated brass tube,
    Last edited by breezy; 4th March 2021 at 06:33. Reason: more info

  9. #24
    Join Date
    18th July 2015 - 16:21
    Bike
    2015 Avanti
    Location
    Hamilton
    Posts
    177
    That glow plug has the idle bar fitted to it. You need to try one without it. Also there is flat coil glow plugs that work well in 4stroke engines. Ontop of that they come in different heat ranges too, and different alloy compositions.
    Neil

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •