weak point of these cranks
-top end bearings --> now cageless solves the problem
-big end bearings failure : partialy solved when rotax changes the crank pin diameter (from 24mm to 266mm for 3d generation crankshaft)
I will have my crank rebuilt soon and I bought skidoo hotrod conrod kit for 717/720 (very reliable sled..) , as they are almost the same (ref 8168 & 8116 hotrod )
PIN LENGTH 52.90 (*) // 52MM (582) (* actually I measured 55mm ??!)
BIG END BORE 33.00 // (31mm 1st gen 582 , 33mm 3d generation)
PIN DIAMETER 26.00 =
BIG END WIDTH 18.00 =
SMALL END BORE 24.00 // 22MM (582)
BIG END BEARING 26X33X18 // 26X32X18
SMALL END WIDTH 18.00 =
CENTER TO CENTER 125.00MM =
WASHER THICKNESS 1 =
SMALL END BEARING 20X24X24 18X22X22 TO BE CHANGED TO 18X24X 3MM : 09263-18015 RN SUZUKI support 30% higher load than cage 18x22x23
crank PIN has to be machined from 26x55 to 26x52 : can be done anywhere .. don't wear the rolling surfaces
main advantages : caged bearing top end with 3mm rollers is easier to manipulate than 2mm cageless , and probably even stronger ( and is cheap : suzuki OEM part is around 12$ one ) .. you can change every decoke / 100h , it will never fail in the interval
Now I was considering replacing big end bearing by loose (cageless) one .. I'm looking for informations on how to do it .. number of rollers to use , retainer dimensions to machine
OEM bearing is 26x33x18 (24x31x17 for those who use 1st generation crankshaft before serial 4172665) . Do anyone know a source of rollers 3.5mm , 13-14mm lenght? with the correct steel nuances (AISI 52100?). Maybe we can extract them from a bearing but I think end is not flat . KYOTO bearings make them at 15$ , whereas some other brands 30 or more
edit : a source here for 3.5x15.8mm (quality? adapted to this use?) , washers exist in 1.5mm Suzuki 09160-26017 26x31x1.5 (but these would require 14.x mm pins)
also SKF rn 3.5x13.8 seems to be fine , good brand . would require 2mmretainer washer
or rn 3.5x15.8 + 2x 1mm washer
or 3.5x17.8 and no washer (but I think the crank washer is too soft for beeing a proper retainer
there is also a cheap way to replace pistons by quality ones : ref 09-772 moly coated SPI is the one a guy lists on ebay for "582UL" but actualy they are just these 583 single rings pistons , which actualy work very well , and cost 120$ pair complete (that he sells double of the price)
water pump seal can be replaced also for reliability to ceramic one
I hope one can have an interesting discution on this engine which is one of the most used 2 stroke in ultralight ...
-top end bearings --> now cageless solves the problem
-big end bearings failure : partialy solved when rotax changes the crank pin diameter (from 24mm to 266mm for 3d generation crankshaft)
I will have my crank rebuilt soon and I bought skidoo hotrod conrod kit for 717/720 (very reliable sled..) , as they are almost the same (ref 8168 & 8116 hotrod )
PIN LENGTH 52.90 (*) // 52MM (582) (* actually I measured 55mm ??!)
BIG END BORE 33.00 // (31mm 1st gen 582 , 33mm 3d generation)
PIN DIAMETER 26.00 =
BIG END WIDTH 18.00 =
SMALL END BORE 24.00 // 22MM (582)
BIG END BEARING 26X33X18 // 26X32X18
SMALL END WIDTH 18.00 =
CENTER TO CENTER 125.00MM =
WASHER THICKNESS 1 =
SMALL END BEARING 20X24X24 18X22X22 TO BE CHANGED TO 18X24X 3MM : 09263-18015 RN SUZUKI support 30% higher load than cage 18x22x23
crank PIN has to be machined from 26x55 to 26x52 : can be done anywhere .. don't wear the rolling surfaces
main advantages : caged bearing top end with 3mm rollers is easier to manipulate than 2mm cageless , and probably even stronger ( and is cheap : suzuki OEM part is around 12$ one ) .. you can change every decoke / 100h , it will never fail in the interval
Now I was considering replacing big end bearing by loose (cageless) one .. I'm looking for informations on how to do it .. number of rollers to use , retainer dimensions to machine
OEM bearing is 26x33x18 (24x31x17 for those who use 1st generation crankshaft before serial 4172665) . Do anyone know a source of rollers 3.5mm , 13-14mm lenght? with the correct steel nuances (AISI 52100?). Maybe we can extract them from a bearing but I think end is not flat . KYOTO bearings make them at 15$ , whereas some other brands 30 or more
edit : a source here for 3.5x15.8mm (quality? adapted to this use?) , washers exist in 1.5mm Suzuki 09160-26017 26x31x1.5 (but these would require 14.x mm pins)
also SKF rn 3.5x13.8 seems to be fine , good brand . would require 2mmretainer washer
or rn 3.5x15.8 + 2x 1mm washer
or 3.5x17.8 and no washer (but I think the crank washer is too soft for beeing a proper retainer
there is also a cheap way to replace pistons by quality ones : ref 09-772 moly coated SPI is the one a guy lists on ebay for "582UL" but actualy they are just these 583 single rings pistons , which actualy work very well , and cost 120$ pair complete (that he sells double of the price)
water pump seal can be replaced also for reliability to ceramic one
I hope one can have an interesting discution on this engine which is one of the most used 2 stroke in ultralight ...
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