Hey fellas,

I came across a vintage trek for sale. It's advertised as a 24-inch 1981 TREK 715/720 Road/Touring Bike. Seller says standover height is 32-inches and suited for a rider 6-ft tall or more. It's burgundy in color with a gray head tube. The seller sent me a picture of the serial number and it looks like it's 086383. Either I'm doing something wrong or the year/size and the serial number don't jive. Can someone please confirm. Thanks for your help.

According to vintagetrek.com. it is an 81, 24inch 710. I believe the 710 frame would have been used for the 715.

I must really be a dumb-dumb and could really use some clarification. From the vintage-trek site, I see the following ranges of serial numbers for various year models (I'm using commas for separators and clarification only):

1980 1 - 1,130
1981 1,131 - 10,265?
1982 10,266? - 42,924
1983 42,925 - 113,648
1984 113,649 - 167,778
1985 167,779 - 224,106
1986 224,107 - 270,975

What are the question marks for the 1981 and 1982 year models? And how does 86,383 fall in the 1981 range? Looks to me like it falls in the 1983 range??? Please help!

Question marks probably indicate uncertainty. The table you referenced contains links to more details by year. Lynn probably followed the 1981 link to a s/n with one fewer digits. The s/n you provided is a 83 model 600 with 22 inch seat tube. So it's not a 24" frame but the stand over height will be approx 32" as advertised- maybe a little under. Assuming the frame is in fact a 22" size that's about right for a 6 foot tall rider.

Exactly right. The 720 is a completely different frame. The chainstays are much longer on the 720 than on the 710/715.

And I think you are right. Sorry to confuse the OP.