You need to be a little more specific. The seller's details are public on Gumtree where they have been a member for 6 years and do not appear to be hiding.
If you were going to buy at what price and did you try a PPSR search with the rego number?
Needs VIN or chassis number. Only $2 on Federal Government website
REVs check | PPSR
2015 Triumph Rocket X 2300cc Limited Edition 283/500 | Motorcycles | Gumtree Australia Port Lincoln Area - Port Lincoln | 1220962231
It has been re-registered and 3rd part personal insurance until 17 Jan 2020 after being renewed since expiring 15/08/2019.
If it is a Rocket X it may be able to find the rest of the VIN
Check Registration Expiry Date
Plate Type ALPHANUMERIC
Plate Number S68AWP
Make TRIUMPH
Body Type SOLO
Primary Colour BLACK
VIN **************4544
They are all 17 character codes
S M T T L C 0 2 3 5
F 6 X 4544 where 'F' the 11th character is 2015, 6 from other Aussie 2015 R3R VINs and
'X', the 13th character is likely to be a 6 or 7 too even though serial numbers are not necessarily batch date related.
1 2 3 4 5 6 7 8 9 10 11 12
13 14 15 16 17
CTP Insurer SGIC
Expiry Date 17/01/2020
My Australian VIN for 2010 model (A) Roadster with ABS with a Dec 2009 manufacturing date.
2015 Model year code for 11th character is 'F'
S M T T L C 0 2 3 5 A 4 3 2 2 6 0
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
A R3R 2014 manufacture SMTTLC0235
E644001
And another 2015 Aussie R3R Roadster VIN SMTTLC0235
F669084
A 2016 R3R SMTTLC0235
G735566
A 2016 manufacture MY2017 R3R SMTTLC3735
H775701
A 2014 MY2015 R3Touring SMTTLC3735
F664720
Note the engines are identical but VIN code for model different. last 6 digits should still be close to R3Rs and RocketX
UK/Europe and Australia does not use USA check digit at all so coding is quite different except last 6 digits and SMT at start is UK (SM) manufacturer Triumph (T).
UK / Europe ISO Standard 3779 system
Vehicle descriptor section (VDS)
The fourth to ninth positions in the VIN are the vehicle descriptor section or VDS. This is used, according to local regulations, to identify the vehicle type, and may include information on the
automobile platform used, the model, and the
body style. Each manufacturer has a unique system for using this field.
I reckon the 6th character 'C' is Rocket
US/Canada and Australia 6th, 7th, 8th code characters are the model type and fairly sure the 9th digit '3' is the number of engine cylinders while 10th digit '5' is probably shaft drive.
C00 = ROCKET III C01 = ROCKET III CLASSIC C02 - ROCKET III + ABS C05 = ROCKET III TOURING C06 = ROCKET III TOURING & AB
Vehicle identifier section (VIS)
The 10th to 17th positions are used as the 'vehicle identifier section' (VIS). This is used by the manufacturer to identify the individual vehicle in question. USA/Canada 10th is year, UK/Europe 11th is year. For Triumph motorcycles 12th-17th is a sequential 6 digit number.
Your 11th character, the digit 6, is 2006 model year in UK / Europe
ISO Standard 3779 system used in Europe and many other parts of the world. Mine is A for 2010.
Date year code is the 10th character for USA / Canada
FMVSS 115, Part 565 system.
This character can be either a digit or an Alpha character
Code =
Year
A = 1980 L = 1990 Y = 2000 A = 2010 L = 2020 Y = 2030
B = 1981 M = 1991 1 = 2001 B = 2011 M = 2021 1 = 2031
C = 1982 N = 1992 2 = 2002 C = 2012 N = 2022 2 = 2032
D = 1983 P = 1993 3 = 2003 D = 2013 P = 2023 3 = 2033
E = 1984 R = 1994 4 = 2004 E = 2014 R = 2024 4 = 2034
F = 1985 S = 1995 5 = 2005 F = 2015 S = 2025 5 = 2035
G = 1986 T = 1996 6 = 2006 G = 2016 T = 2026 6 = 2036
H = 1987 V = 1997 7 = 2007 H = 2017 V = 2027 7 = 2037
J = 1988 W = 1998 8 = 2008 J = 2018 W = 2028 8 = 2038
K = 1989 X = 1999 9 = 2009 K = 2019 X = 2029 9 = 2039