so, i just found out that my bike with 265 miles on the clock, has had a motor swap, and this motor is potentially old as balls. It runs pretty well, misfires at around 2k but other than that it's pretty good. I really want to know how old this motor is tho, it probably has like 50k on it or something, as long as it runs i don't really care tho. Is there any way to look up when the engine was manufactured, i notices there's a number or code on the motor?

Hi there,
Yes, the engine number, which is stamped into the engine case on the top left side, I believe, under where the carbs are, will help you determine the date of manufacturing.
Check the Wiki for the GS500 year-by-year database, and you should find the engine number range that coincides with the year of the engine.
Good luck,
Trwhouse

well the only number i could find on the motor was on the right side, next to the dipstick. It is M504-111237. I couldn't find any other number. help?

Made in 2004, if I understand the code correctly. M = 400~499cc and 5 = four-stroke twin, the '04 meaning the year.  Last is serial.

If it's got a factory oil cooler, it can't be older than 2004.

huh, it's just strange that all the bolts have removal marks, some are newish, and there are scratches on top of the motor, where it can't get scratched unless it was removed because the frame and tank are in the way. weird stuff.

I just went and looked at my serial.. I bought it new in 05 and the serial also starts with M504 so that makes sense.

my 05 motor starts M504

89-00 GS'es are M-501. Newer is M-504.
Bolts with tool marks, maybe when they cranked them down at the factory they put some tools on them ... 
BTW the factory cranks these things till they turn blue. 90% of the bolts are over tightened.
Cool.
Buddha.

buddha i'm not an idiot. read what my post. there are REMOVAL marks on the bolts. is there any way to look up exactly what year?

maybe im dumb but how can you tell the difference from a mark a tool makes putting it in from taking it out?

+1

haha +2

sockets are never a perfect fit, when you tighten a bolt there will be a mark on the right side of each flat edge where the socket grabs the bolt, if you remove a bolt that was initially tightened to hell like all the bolts holding in the motor on our bikes, it will put a mark on the left side of each flat edge. Am I seriously the only one who knows this?

I can see the basis of the idea, but anyone whose experiencing it needs better tools.

well if you just got the bike and you can prove that its had a motor swapped contact someone about the bike being sold as fraud

Any dealership can match the engine and vin numbers

Quote from: makenzie71 on February 08, 2009, 08:14:35 PM
Any dealership can match the engine and vin numbers

Yeah, in many states the original engine number is on the title with the VIN. California is this way... Also, how do you know the engine was swapped? Perhaps someone took it out to paint the bike or do some work on it... Perhaps the PO did something stupid like float the valves into the pistons during the break-in period and someone had to go and fix it... Perhaps someone noticed that all the bolts were over tightened and decided to bust out the torque wrench and fix them all because they were paranoid. Who knows? Also, you mention scratches on the top of the motor, are you talking about the valve cover? If so, be glad someone was in there checking your valves. It takes mere minutes to get the tank off the bike and there are lots of reasons to do it, so scratches on the top of the engine are not a sign the engine was out of the bike. Perhaps someone was cleaning the air filter and dropped a wrench...

Quote from: fred on February 09, 2009, 01:07:12 AM

Quote from: makenzie71 on February 08, 2009, 08:14:35 PM
Any dealership can match the engine and vin numbers

Yeah, in many states the original engine number is on the title with the VIN. California is this way... Also, how do you know the engine was swapped? Perhaps someone took it out to paint the bike or do some work on it... Perhaps the PO did something stupid like float the valves into the pistons during the break-in period and someone had to go and fix it... Perhaps someone noticed that all the bolts were over tightened and decided to bust out the torque wrench and fix them all because they were paranoid. Who knows? Also, you mention scratches on the top of the motor, are you talking about the valve cover? If so, be glad someone was in there checking your valves. It takes mere minutes to get the tank off the bike and there are lots of reasons to do it, so scratches on the top of the engine are not a sign the engine was out of the bike. Perhaps someone was cleaning the air filter and dropped a wrench...

quite possibly, and what trwhouse said, somewhere in the engine is a number thsi will have a manufatcurint date roughly when it was made

Contact Suzuki customer care and ther will answer the question.

http://www.suzukicycles.com/Inside_Suzuki/ContactUs.aspx?#FINDDEALER