Yamaha AT1

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Yamaha AT1
ManufacturerYamaha Motor Company
Parent companyYamaha
Production1969–1971
Predecessorn/a
SuccessorAT2, AT3
ClassEnduro
Engine123cc, 2-stroke petrol
Top speed60 mph (97 km/h) plus
Power11.5 BHP/7,500 r.p.m
Torque8.5 ft-lb/6000 r.p.m
TransmissionWet, multiple disc
SuspensionFront: Telescopic fork, Rear: Swinging arm
BrakesInternal expansion
Wheelbase50.6 in (1,290 mm)
DimensionsL: 77.2 in (1,960 mm)
W: 35.8 in (910 mm)
H: 42.9 in (1,090 mm)
Weight218 lb (99 kg) (dry)
234 lb (106 kg) (wet)
Fuel capacity1.9 US gal (7.2 L; 1.6 imp gal)
Oil capacity1.3 qts
Fuel consumption141.1 mpg‑US (1.667 L/100 km; 169.5 mpg‑imp) at 25 mph
Turning radius75.1 in (1,910 mm)

The Yamaha AT1 is a single cylinder enduro/adventure bike produced by Yamaha motor company from 1969 to 1971.

The Yamaha AT1 was available in three different models, each corresponding to the year of production. 1969 Yamaha AT1, 1970 Yamaha AT1B, 1971 Yamaha AT1C. Each year the AT1 was also available in the Motocross edition designated by an M. The M models were very similar to the regular models other than a few performance enhancing features, such as weight reduction, higher compression ratio, tuned exhaust, larger carburettor with 26 mm throttle bore, tuned gearing ratio, etc.

Engine and transmission[edit]

Bore & Stroke 56 x 50mm
Compression ratio 7.1:1
Lubrication System Yamaha Autolube
Starting system Electric for Enduro Versions and kick starter
Carburettor VM24SH
Battery 12V 7AH
Ignition system Battery ignition

Models and VIN[edit]

AT1 1969 Pearl White AT1-100101 to AT1-119829
AT1M 1969 MX Version Pearl White AT1-300101 to AT1-303790
AT1B 1970 Competition Yellow AT1-120101 to AT1-138890
AT1M-B 1970 MX Version Competition Yellow AT1-310101 to AT1-312326
AT1C 1971 Brilliant Red AT1-139101 to AT1-162879
AT1M-C 1971 MX Version Brilliant Red AT1-313101 to AT1-317191