O.S. 60GT
09-24-2012, 01:18 PM
#26
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RE: O.S. 60GT
ORIGINAL: wyo69cowboy
Hope we get some more photos soon of the crank and bearings, etc. It does appear to be an aluminum rod, which is the first large gasser I can think of with that feature. I asked a while back on one of these forums about steel vs aluminum rods, especially in the small 20cc size, and the answers were generally that steel was used for durability...
Hope we get some more photos soon of the crank and bearings, etc. It does appear to be an aluminum rod, which is the first large gasser I can think of with that feature. I asked a while back on one of these forums about steel vs aluminum rods, especially in the small 20cc size, and the answers were generally that steel was used for durability...
09-24-2012, 01:34 PM
#27
RE: O.S. 60GT
Using a steel rod lets you harden the ends of the rod and use it for the outer race for the needle bearings, then with a hardened crankpin and wrist pin you can save a lot on how big the rod is overall. Using a aluminum rod is not a problem as they have done it for many years on engines, such as motorcycle engines for example. But then the needle or roller bearings need to be made with at least a outer race then.
Does the OS engines use a special OS carb that is incompatible with Walbro parts? Although OS makes some really good engines, it would be nice to have a way to at least replace the diaphragms if the need arises. I don't remember seeing rebuild kits for their gasser engine carbs.
Does the OS engines use a special OS carb that is incompatible with Walbro parts? Although OS makes some really good engines, it would be nice to have a way to at least replace the diaphragms if the need arises. I don't remember seeing rebuild kits for their gasser engine carbs.
09-24-2012, 01:38 PM
#28
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RE: O.S. 60GT
ah so...didn't know that. Just a few Brisons around here, and very few FPE's, if any, that I've seen, but the Brison's do have a good reputation FWIW. I've always wondered about the aluminum rod usage, thinking it would be lighter, but didn't account for the hardened steel rod being the outer bearing "race"; therefore making a simpler bearing setup. Maybe no weight penalty either way if done right...
09-24-2012, 11:08 PM
#30
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RE: O.S. 60GT
aluminium rods are lighter. Even a 2 gr saving has a benefit when we look at the acceleration of the conrod. The designer wants the lightest and strongest piston and rods that can be built to last the projected lifespan of the engine.
09-25-2012, 05:57 AM
#31
Senior Member
RE: O.S. 60GT
ORIGINAL: TimBle
aluminium rods are lighter. Even a 2 gr saving has a benefit when we look at the acceleration of the conrod. The designer wants the lightest and strongest piston and rods that can be built to last the projected lifespan of the engine.
aluminium rods are lighter. Even a 2 gr saving has a benefit when we look at the acceleration of the conrod. The designer wants the lightest and strongest piston and rods that can be built to last the projected lifespan of the engine.
09-25-2012, 06:00 AM
#32
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RE: O.S. 60GT
ORIGINAL: MTK
Hmmm! Weighing rods from an SAP 180HP (tungsten steel) and a rod from a DLE30 (aluminum) the lighter one is the tungsten steel by about 15%....I was surpised at that finding too. Todd Syssa designed his rods for super strength yet low weight regardless of cost, which doesn't mean every manufacturer would use the stronger but much more expensive rod. I've owned two Syssas and run them hard for two years, and have followed the Syssa thread for 3 years. I have not had nor heard of one issue with the rod
ORIGINAL: TimBle
aluminium rods are lighter. Even a 2 gr saving has a benefit when we look at the acceleration of the conrod. The designer wants the lightest and strongest piston and rods that can be built to last the projected lifespan of the engine.
aluminium rods are lighter. Even a 2 gr saving has a benefit when we look at the acceleration of the conrod. The designer wants the lightest and strongest piston and rods that can be built to last the projected lifespan of the engine.
09-25-2012, 08:50 AM
#34
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RE: O.S. 60GT
MVVS and Evolution have aluminum rods also,i never had a problem with them.
some where i seen a price for the OS60 in Yen and had been converted to USD, it came out to 870.00 if i remember it rite.
some where i seen a price for the OS60 in Yen and had been converted to USD, it came out to 870.00 if i remember it rite.
01-06-2013, 09:48 AM
#37
RE: O.S. 60GT
when lightening a rod by using aluminum you don't have to lighten the whole rod(simply weighing a complete aluminum or steel rod would tell you little about what one was actually lighter. you need to weigh the top 1/3 of the rod) ,generally only the top 1/3 of the rod is considered reciprocating mass ,the lower 2/3 of the rod is considered rotary mass and only this mass is included when balancing the cranks rotary mass. yep you guessed it you can not balance reciprocating mass in a single and that is why it's so critical to keep weight down in the top end of a engine (as RPM doubles the weight of the reciprocating mass squares )
this is also why a twin runs so smooth the piston counters the weight of the opposing piston if the designer gets it right and the rotary mass is balanced well you will have a limited vibration 90 degree from the reciprocating mass and you have your self a smooth engine.even in this case it is beneficial to have the top end as light as possible , the lighter it is the more HP it will produce because less energy will be spent trying to overcome the weight of the piston.
the problem is there is no exact science for how much rod to include when balancing rotary mass ,it's more like voodoo LOL .and as you know many get it wrong.Roger
this is also why a twin runs so smooth the piston counters the weight of the opposing piston if the designer gets it right and the rotary mass is balanced well you will have a limited vibration 90 degree from the reciprocating mass and you have your self a smooth engine.even in this case it is beneficial to have the top end as light as possible , the lighter it is the more HP it will produce because less energy will be spent trying to overcome the weight of the piston.
the problem is there is no exact science for how much rod to include when balancing rotary mass ,it's more like voodoo LOL .and as you know many get it wrong.Roger
03-22-2013, 06:09 PM
#41
RE: O.S. 60GT
I want to use it in a Ziroli Stuka. I'm more interested in reliability, sound level, ease of use, etc...
If you don't mind me asking, which magazine was it? I'd like to read it.
I found this from http://www.keimod.com/shop/product_i...roducts_id=747
INCLUDES: O.S. GT60 Gasoline Engine, IG-02 Electronic Ignition, CM6 Spark Plug, Instruction Manual
SPECS:
Displacement: 3.656 (59.91cc)
Bore: 1.732" (44.0mm)
Stroke: 1.551" (39.4mm)
RPM Range: 1,600-8,000 RPM
Output: 6.00 hp @ 7,000 RPM
Weight: Engine, 49.38 oz (1400 g)
Ignition module, 3.7 oz (105 g)
Suggested Propeller Size and RPM Data:
22x8 7,650 RPM
22x10 6,900 RPM
23x8 7,000 RPM
24x8 6,550 RPM
24x10 6,150 RPM
If you don't mind me asking, which magazine was it? I'd like to read it.
I found this from http://www.keimod.com/shop/product_i...roducts_id=747
INCLUDES: O.S. GT60 Gasoline Engine, IG-02 Electronic Ignition, CM6 Spark Plug, Instruction Manual
SPECS:
Displacement: 3.656 (59.91cc)
Bore: 1.732" (44.0mm)
Stroke: 1.551" (39.4mm)
RPM Range: 1,600-8,000 RPM
Output: 6.00 hp @ 7,000 RPM
Weight: Engine, 49.38 oz (1400 g)
Ignition module, 3.7 oz (105 g)
Suggested Propeller Size and RPM Data:
22x8 7,650 RPM
22x10 6,900 RPM
23x8 7,000 RPM
24x8 6,550 RPM
24x10 6,150 RPM
03-23-2013, 04:43 AM
#43
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RE: O.S. 60GT
We tested the OS GT-60 a couple of weeks ago. It was 18F out and it turned a Mej 24-10TH at 5950 RPM and was 89 dBA @ 20 feet with the stock, supplied muffler. However, it started backwards about 1/2 the time.
03-24-2013, 02:24 PM
#44
Senior Member
RE: O.S. 60GT
I saw that MAN review. I wasn't surprised at the numbers their test guy got. I think it was the same guy that got 4600 rpm on the 33GT turning a 20x10. Well, it just ain't so....But as always, YMMV
