Question 1

Does this Cap Barbell causes cancer?

Accepted Answer

Well... I guess I'll be the one to blow everyone's mind. First let's address the question. "Does this Cap Barbell causes (sic) cancer?" 
Answer: Probably not. I would almost guarantee that it doesn't.

Now, why was the question asked? 
Answer: Some years ago California passed 'Proposition 65', which requires any company selling products to customers in California 'to provide “clear and reasonable warnings” before knowingly exposing people to any chemical on the (Proposition 65) list, unless the expected level of exposure would pose no significant cancer risk.' Interestingly, CAP BARBELL, INC. just so happens to have a big "PROPOSITION 65" button on the header of their website which explains this in detail. Strange that a company that primarily sells barbells would have this so prominent and centrally focused on their website. Here's why...

You see, CAP BARBELL, INC. reached a settlement in 2016 for selling products that violated Proposition 65. These products were "Vinyl Sauna Suits,
including but not limited to “CAP Fitness® HHS-CF001, Vinyl Sauna Suit.
‘DD’s Discouts SKU: 400131044995’ Made in Taiwan. UPC: 7 02556 01803 3”". These were sold without providing a label indicating the cancer risk posed by some of the materials used in the fabrication of these products. This is no longer of concern as it's since been addressed, and Cap is probably keeping an eagle-eye trained onto their products at this point. (They settled for $45,000 which is a slap on the wrist, but a second infraction is never taken lightly by the legal system). As you can imagine, Vinyl Sauna Suits are a type of product that would be of much higher risk than something like a steel barbell. So it's probably fine.

Although, I'd like to point out another product from a different brand that should illuminate another possible source of concern of the poster of the original question. If you navigate to Walmart's website and search the "Gold's Gym 110-lb. Olympic Barbell Weight Set" and scroll to the bottom of the listing you'll read "WARNING: Cancer and Reproductive Harm - [WEBSITE LISTING REMOVED BY AMAZON]" Either this is an indication that some kind of coating or packaging used in the manufacturing of this other barbell is hazardous, or it was a preemptive (C.Y.A.) legal response to the recent settlement with CAP BARBELL, INC. I tried plugging the Gold's Gym barbell link into 'Wayback Machine' to see when this warning label was added, but the URL had never been cached. Luckily, CAP barbells are also listed on Walmart's website, and if you compare those listings to the Gold's Gym barbell listing, they do not have the Prop65 warning, which indicates to me, though not with certainty - that they do not pose a health risk.

Conclusion: I would seriously doubt, after the 2016 settlement - the same year this question was originally asked - that CAP would risk another lawsuit. Since the Barbell listings do not mention Prop65 on either Amazon or Walmart, I think it's safe to assume this product does not contain any known cancer causing chemicals.

Sources: 
Well apparently I can't list links or Amazon automatically deletes my reply. So, source: "Trust me bro"

Question 2

how easily do the sleeves spin?

Accepted Answer

This is Steve  the sleeves spin pretty good,  I occasionally put the bar on the end and put a few drops of oil where the bushing is and leave overnight ... The sleeves spin better with weight on them  ... This is  more of a power bar than a weightlifting bar ... But for the price this is a really good bar ,as good as ones costing twice as much ..

Question 3

Does the bar loosen up and spin easier once it's used a little. I wanted it mainly for snatch & clean & jerk training.

Accepted Answer

It is broken in rather well.. we use this bar weekly for snatches, cleans, jerks and presses.. We've got three of these bars and they get tons of crossfit use and abuse.. They hold up extremely well. Couldn't be more happier with these bars.

Question 4

Does this bar have center knurling?

Accepted Answer

I just checked my TWO Cap 1000 pound barbells that I ordered here on Amazon and neither of them have centered knurling. The center area is smooth. They do have two areas on each side that have knurling (or if you want to think of it as one long knurling area on each side separated by a small thin smooth stripe in the middle of the knurling). The width of the smooth area within the knurling is less than the width of my pinky finger. But, I use that smooth area on each side as a marker for hand placement on the bar.

ASIN	B09Z1BXM53
Best Sellers Rank	#19,233 in Sports & Outdoors ( See Top 100 in Sports & Outdoors ) #35 in Strength Training Bars
Brand Name	CAP Barbell
Customer Reviews	4.6 4.6 out of 5 stars (4,677)
Finish Type	Black Phosphate
Grip Size	30 millimeters
Grip Type	Knurled
Item Dimensions L x W	15"L x 28.5"W
Item Weight	44 Pounds
Manufacturer	CAP Barbell, Inc.
Material	Alloy Steel
Model Number	OBIS-86B
Mounting Hole Diameter	2 Inches
Part Number	OBIS-86B
Shaft Diameter	28.5 Millimeters
Shaft Length	51.5 Inches
Sleeve Length	15 Inches
UPC	702556304358
Weight Capacity Maximum	1200 Pounds

Pro Series 7FT Olympic Barbell, Weightlifting Bar for Strength Training

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