Landracing Forum

Bonneville Salt Flats Discussion => SCTA Rule Questions => Topic started by: donpearsall on January 28, 2008, 12:05:04 AM

Title: How to tell tire manufactured date?
Post by: donpearsall on January 28, 2008, 12:05:04 AM
The rulebook says that all M/C tires must have been manufactured within the last 10 years and the sidewall code will be checked. Where & what is the sidewall code? I can't find any dates on the Metzler tires on my bike and am not sure when they were manufactured. Anybody know?

Thanks
Don
Title: Re: How to tell tire manufactured date?
Post by: Seldom Seen Slim on January 28, 2008, 10:33:53 AM
On one sidewall or the other there'll be some D O T letters, followed by a number -- usually heat embossed into the tire.  The number will end with four digits that are the date code (have been since year 2000)/  The first two digits are the week (of the year) of manufacture, the second two are the last two of the year number.  That is, for instance, 0800 would indicate the tire was made the eighth week of year 2000.  4107 would mean the forty-first week of 2007. 

Got it?
Title: Re: How to tell tire manufactured date?
Post by: bak189 on January 28, 2008, 10:45:33 AM
" It is recommended that tires are rated for the appropriate speeds, and use is at the sole discretion of the owner/participant.  The rider has the sole responsibility of inspecting the condition of the tire before and after each run."

BUB MOTORCYCLE SPEED TRIALS......2007
Title: Re: How to tell tire manufactured date?
Post by: donpearsall on January 28, 2008, 05:20:22 PM
Thanks for the info. On my particular set of Metzlers (bike built in 1983), there is a DOT lettering, but no numbers near it. I do see some numbers in a little embossed area on the tire that say 3400, may be that is it, but I can't be sure.

Don
Title: Re: How to tell tire manufactured date?
Post by: jimmy six on January 28, 2008, 05:28:55 PM
The embossed area is normally an oval and has the 7#'s in 2 groupings. Many years ago it was 6 #'s. As I remember it the last group of 3 were the year. The first 2 the week and the last the last digit of the year. The first group was the mold. When I work at Sears in the 60's we always tried to group the 4 tires with the same #'s. This assured they were equal in size. Most sales folks and tire installers have no idea you can do this. I would guess it's the same today. Even if they were different weeks I would like the same mold....Good Luck JD
Title: Re: How to tell tire manufactured date?
Post by: willieworld on February 24, 2008, 12:41:52 PM
don i think that you misread the rule book it says all production tires rated v  z or zr must have been produced within the last 10 years -- not all tires --so acording to the rules race tires that wernt v  z or zr rated wouldnt apply to this rule (h wouldnt apply also)    willie buchta
Title: Re: How to tell tire manufactured date?
Post by: Dean Los Angeles on February 24, 2008, 04:37:52 PM
The only tires with a date code are DOT tires that would also have a speed rating. Since there is a handy date to inspect, the ten year rule is easy to apply. Ratings below V (131 mph) aren't much of a problem from coming apart at speed, which I think is the main criteria.

Non-DOT racing tires may not have a date code, but I doubt you are going to have much luck with inspection if the tire visibly looks old and possibly unsafe.

I doubt if anyone much cares what you run as long as it is safe and doesn't leave gouges on the racing surface.

Some of the streamliner tires are pretty suspect from an age stand point, but everybody understands the supply of tires is limited and the entrant understands the risk.