Questions about Jensen #70

• Questions about Jensen #70
  Posted by ShadetreeMotorcycle on 31 May, 2021 10:26
• Am I correct in thinking that as the Jensen 70 is a double acting occillator, will it run in both directions cheerfully?
    The reason for my question is I am on the hunt for a suitable Cylinder assembly that may offer big power gains as an upgrade mod to a Mamod Roadster SA1.
    I prefure the efficiency of a slide valve engine, I suppose a D10 or even a D16 could be fitted, but the Jensen 70 would be a more simple mod (I think)
    I am also open to other makes and models. I Love the little reversing lever on the Mamod (looks cool) but in my quest to make the Roadster perform, I am thinking of eliminating the lever as a potential steam loss, I may remount it(lever) or a more decorative version for looks.
    Sorry about all the Jensen questions, they are largely unknown to me, but I did see the Jensen 70 has .500 bore, where as the Jensen 85 is .4375, vs stock Mamod is only .3125 and single acting, so I am after the extra power (hopefully)
     I do realize the Roadster suspension was not designed for a great deal of speed, but I have a nice tennis court in a park near me that would offer smooth higher speed motoring
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• #1 Reply
  Posted by Steamloco on 31 May, 2021 10:31
• The Jensen 70 has a double acting cylinder, but only rotates in one direction.
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• #2 Reply
  Posted by Stoker on 31 May, 2021 10:48
• It is capable of running in either direction, but would need special re-plumbing and steam-line valving to make it happen.
  
  Do realize that bigger cylinder require more steam to create the greater power that they are capable of, such that I think the Mamod boiler would not be able to provide all the steam needed to realize your concept with significantly larger cylinders.
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