I found this serial number tag on my harley davidson but I dont think that it makes my bike's vin. tag says: 7910R303030183 vin: 1HD1BHY101Y025637

Your HD service department can tell from the VIN number.

This is a problem with your title. I'd consult the DMV about this. Here, as long as the VIN is correct as it appears on the frame, everything is fine. Some states use the engine number as their VIN number. Either way, the VIN should be the same as the one on your bike. Talk to the DMV about this.

Good Luck
steve

It' sounds like you've got an FXEF, the first Fat Bob bikes. To know for sure, you need to go by the frame number. Got to any site that list the "harley alphabet" to decode your frame VIN number. I'm pretty sure the "7G" designation on the engine indicates the 80" engine that was standard from 1980 on. The 80" engine was available prior to 1980 through special order only. The serial number (last five digits or so) should match the last five digits on your frame.

Good Luck
Steve

You can determine the exact year and model of your bike by look at the frame VIN number. Then, go to this site and look up what each letter or number means in the VIN on your bike.

http://www.cyclemanual.com/faq.htm

Good Luck
STeve

Since tag numbers change, you'd have to do a search by the VIN number of the bike.

http://www.motoverse.com/tools/vin/harley.asp
make sure the head tube is clean and you have all right numbers/letters, the link i gave you will help you find out what it is.
sorry i can't be more help good luck
Mark
C.C. Motorsports

The full VIN number on your bike is stamped on the side of the steering head of the frame. The number on the engine is an abbreviated number but the two numbers should match.

Yes, it's called a VIN number. The VIN number will tell you everything about the bike. I think the seventh digit is the "engine size" designator. You'll need a book that tells you how to read the VIN numbers on a Harley for that year. I would just tell you but I don't have a book that is that "late".

I'm sure it has or had some meaning to it. Here's a link that you can find HD VIN decoders at. If it has an interesting meaning, let me know. I've never really given the VIN much thought.