Terryd | 09/03/2012 10:20:59 |
![]() 1946 forum posts 179 photos | Hi again Ramon, Found it, 'twas in the 'Message to Webmaster' thread. Here are his instructions:- John, To avoid the resizing thing happening, this is what I did:
Example:
Hope that helps to clarify it, Best Regards, Terry |
rich lowe | 09/03/2012 23:08:13 |
15 forum posts 6 photos | Thankyou Ramon, well basically the liner is missing and looking for one to go in, or at least get dimensions to get one made, but preferably i would like to buy one. i am not to worried about the intake yet, although i might chase one up at a later date, or as you said, get a venturi insert turned and tapped. Best Regards, Rich Edited By rich lowe on 09/03/2012 23:08:42 |
Ramon Wilson | 10/03/2012 14:05:58 |
![]() 1655 forum posts 617 photos | Thanks for the instruction Terry I think I shall be okay with it now. Rich, Unfortunately I'm afraid I can't part with the piston / liner that I have but you may be able to pick up an old 'externally abused' example of a Rapier somewhere - good examples of the early green head versions can certainly fetch a few bob but the later ones are not quite so sought after. The dimensions (mm) of this set up are as follows.... Overall length of liner - 32.1 Distance from bottom of liner to exhaust flange - 10.5 Thickness of exhaust flange - 3.75 Diameter of exhaust flange - 21.7 Diameter above exhaust flange - 17.99 (good slide fit into cylinder head) Diameter below exhaust flange - 18.1 (Not critical, the annular gap acts as one big transfer passage) Width of exhaust and transfer ports is 1.58 (1/16) (The top of the transfer port is level with the bottom of the exhaust flange. The exhaust port lower edge is set .8 above top of transfer port ) Bore is 14.67 Piston wall height - 10.8. Piston has a conical top - overall height is 13.25 Pin offset from top of wall is 6.5 Con-Rod length is 24.4 This liner is hardened but were I to make one for myself I would use ordinary EN1a which is a good combination with a cast iron piston. If you already have a piston in reasonable condition it would probably be worth re-lappping this first then make the liner a thou or so down on the piston size to allow for lapping the liner. One other point - the four exhaust and transfer ports are cut such that the pillar left between them is very small ( I believe some engines were made with three ports) Personally I would cut these less deep to give a wider pillar say 3-4mm wide. This will have very little if no effect on performance but will make for a stronger liner. Reclaiming small engines like this has always given me a great deal of satisfaction so good luck with yours Regards - Ramon |
rich lowe | 10/03/2012 15:29:47 |
15 forum posts 6 photos |
Thankyou so much Ramon, this is a big help and is greatly appreciated. And i strongly agree, there is so much satisfaction in getting these engines running again. I cant help but mention how much i admire your skills. I saw some of the pictures of when you was building an engine from scratch, excellent job Well, as i said, thankyou so much for your help, i can see getting this engine running again isnt as far away as i originally thought.
Best Regards, Rich |
Ramon Wilson | 10/03/2012 15:57:40 |
![]() 1655 forum posts 617 photos | Glad to be of help Rich - don't forget to tell us when it's up and running. Regards - Ramon |
rich lowe | 10/03/2012 16:10:20 |
15 forum posts 6 photos |
will do, |
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