Author Topic: a very small 4 stroke engine : 1.35cm3  (Read 3847 times)

Offline Zephyrin

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Re: a very small 4 stroke engine : 1.35cm3
« Reply #45 on: March 16, 2021, 08:41:19 AM »
Hi,
nothing new in the future carburettor Roger : a simple 2 needle model carburettor with an air valve that moves as it rotates and decreases the fuel intake while closing the air, a little bit smaller.
For miniaturization, I look carefully at your posts!

Offline Johnmcc69

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  • Erie Pa., USA
Re: a very small 4 stroke engine : 1.35cm3
« Reply #46 on: March 16, 2021, 03:14:47 PM »
 :ThumbsUp:
 Looking good Zephyrin!

 What did the final gear ratio work out to be?

 John

Offline Zephyrin

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Re: a very small 4 stroke engine : 1.35cm3
« Reply #47 on: March 17, 2021, 10:28:33 AM »

Thanks John !
 This diesel shunter drags at about 50 km/h on the track, so 265 rpm for its 1 m wheels; value which has to be kept on the Gauge 1 scale model (1/32), that is 300 rpm (which gives an actual speed of 2 km/h on the model with 34 mm dia wheels).
Therefore, a 15 times reduction of the engine speed (4800/300) should be in the right range.
This is what I got with a fixed reduction of 6, followed by a variable reduction on the friction drive of about 3 to 0.9 ( about 1.5 at the middle), and a final reduction of 1.66 on the loco's axles.
I would clearly prefer faster locos...but unrealistic for the trains buffs at the club

Offline Johnmcc69

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Re: a very small 4 stroke engine : 1.35cm3
« Reply #48 on: March 20, 2021, 06:09:12 PM »
 :ThumbsUp:
 Thanks Zephyrin!

 John