KOS Racing

So you have decided to purchase a set of sliders, swing arm spools, bar ends or whatever the part may be or whatever the name it is a manufacturer calls it. The bottom line is you are thinking about protecting your bike. Now that you have decided to protect your investment there is the daunting task of trying to figure what company to buy from. With all the branding out there, different styles to different materials, it can seem overwhelming.

On this page we are not out to bash one product over another (we will leave that up to others who feel the need to do that). What we want to accomplish here, is to make your decision making a little easier. The more knowledge you have the better educated you will be when making your final decision.

Lets first talk about the different materials that are out on the market right now and some of the reasons they are being used. You have probably heard the terms Delrin, Acetal, Nylon and even Aluminum used when discussing bike saving parts. So what are they and what are some of the differences?

Well to start out, the appearance of the parts being produced are one of the major deciding factors in what product people buy for their bike. While we understand this and always keep this into consideration when designing out parts, there are some other things to consider as well. Lets take Aluminum for instance. It can be brightly polished, anodized (meaning coloring the aluminum), powder coated and engraved. The aluminum products on the market today (as far as bike protection) add more of a custom look than they do than act as proper protection. In the event of a "tip-over" they will provide adequate protection. However in a higher speed crash Aluminum tends to "grab" or "bite" in the concrete or asphalt or most any surface you may be riding on. So what does that mean? Well, to be right to the point, that means that the slider, spool or bar end wont "slide" across the surface as easily, the key word here is easily, they can still slide, as well as they can provide enough protection. This means it can cause excess damage to your bike, if there are sudden bursts of grabbing, it may and very well could send your bike into a flip, well lets just say that's not something you want.

Crashes are unique and the end result is not the same from crash to crash. So if you hear people talking about their crash compared to someone else's and the fortune or misfortune they had with a particular part, may not be the same for you or for the next person.

Next on the list is Delrin/Acetal and Nylon. We have narrowed down the "plastics" out on the market to these as we feel these are the two most common plastics manufacturers are using, and the most talked about for use in crash saving frame sliders, swing arm spools and bar ends. As you can see from the list there are numbers for and against each type of plastic. After looking over the table you are probably no better off now than you were before you came across this page. So what do these numbers mean?

There are three main reasons we chose the Acetal plastic to use as our frame sliders, swingarm spools and bar ends. The compressive strength, impact strength and deformation under load. The Acetal out performs in these categories over the Nylons listed in the chart. We felt that the impact to compression to deformation are the most common "actions" that happen in a crash, and typically in that order. With Acetal/Delrin out performing Nylon in these categories we decided to manufacture our products with this material. Now keep in mind that there are places where Nylon outperforms as well, and people will and do, argue Nylon is better.

So Delrin/Acetal/Nylon compared to Aluminum, the major difference here is that these plastics tend to "slide" better than the Aluminum, therefore in theory should reduce the "flip" factor caused by a frame slider, swing arm spool or even bar ends. BUT, that doesn't mean a slider or spool or bar end made from plastic will remove this excessive damage from happening in a crash. What we are trying to do is reduce the chances of it happening by providing a product made out material with properties that lie in that favor.

Property	Units	Nylon MD & MDS	Nylon 6 or Nylatron, Unfilled®	Nylon NSM	Nylon GSM	Delrin® Acetal
Water Absorption (24 Hours)	%	1.2	1.2	0.25	1.2	0.25
Water Absorption (Saturation)	%	6.5	9	7	6.5	0.9
Tensile Strength	PSI	12,500	12,400	11,000	12,500	10,000
Flexural Strength (73° F)	PSI	16,400	14,000	16,000	16,400	14,300
Compressive Strength (10% Deflection)	PSI	10,000	12,000	14,000	10,000	18,000
Shear Strength (73° F)	PSI	11,000	9,600	10,000	11,000	9,500
Impact Strength, Notched Izod	Ft-Lbs/In.	.8-1.0	1.2	0.5	.8-1.0	1.5
Property	Units	Nylon MD & MDS	Nylon 6 or Nylatron, Unfilled®	Nylon NSM	Nylon GSM	Delrin® Acetal
Elongation at Break (73 °F)	PSI	400,000	400,000	410,000	400,000	450,000
Flexural Modulus of Elasticity (73 °F)	PSI	400,000	410,000	475,000	400,000	425,000
Hardness - Rockwell & Burnell (73 °F)	Various Scales	R120	R120	R110	R120	R120
Density	Lbs/cubic Inch	0.041	0.0415	0.0415	0.0418	0.051
Coefficient of Friction (Dynamic)	None	0.35	0.35	0.18	0.35	0.25
Wear Factor (K)	In-min/Ft-Lbs-Hr	8	72		83	216
Limiting PV	PSI/FPM	3,000	2,700	12,300	3,000	2,700
Property	Units	Nylon MD & MDS	Nylon 6 or Nylatron, Unfilled®	Nylon NSM	Nylon GSM	Delrin® Acetal
Abrasion Resistance Index	None	-	54	-	-	137
Coefficient of Linear Thermal Expansion	In/In/F	5.0x10⁵	5.0x10⁵	5.9x10³	5.0x10⁵	5.0x10⁵
Continous Service Temperature - in Air (max.)	F	212	212	200	212	180
Deflection Temperature (264 PSI)	F	200	194	200	200	260
Melting Point	F	430	491	420	430	347
Deformation Under Load (2000 PSI, 122 °F)	%	0.75	2	-	0.75	0.6
Dielectric Strength	Volts/Mil	550	400	-	550	380
Property	Units	Nylon MD & MDS	Nylon 6 or Nylatron, Unfilled®	Nylon NSM	Nylon GSM	Delrin® Acetal
Dielectric Constant (1 kHz)	None	3.7	4.1	-	3.7	3.7
Dielectric Constant (1MHz)	None	3.7	4	-	3.7	3.7
Dielectric Constant (60 Hz)	None	3.7	3.4	-	3.7	3.7

This debate will never end until there is technology that makes it to the market in an affordable price to use to make the sliders, spools or bar ends out of.

As we said earlier the appearance of the products is still a major deciding factor, this is where we feel we are a leader in the market today. Now you can feel confident purchasing from KOS Racing knowing we do manufacture all of our products in house! And do research on the products we develop. We offer all of our products in a wide range of color choices to help add that custom look to your bike.

Thanks for stopping in!

The KOS Racing Team.