Fourcroy's 411 Bultaco Service Center


Bultaco ID  


Mobley's Bultaco

Speed and Sport



Oil - Amounts

Fuel Golden
Spectro Oil
50:1 ratio
Forks 210 ml 30 wt.
Primary 300 ml 30 wt.
Transmission 600 ml 70-90 wt.

Torque Chart:

Engine     Suspension  
Engine Mounting Bolts 35 ft/lb Front/Rear Axel Nuts 30 ft/lb
Front Sprocket 90 ft/lb Swing Arm 75 ft/lb
Flywheels & Clutch Hub 75 ft/lb Fork Caps 50 ft/lb
Seal Retainer 5 ft/lb Axel Clamp 6 ft/lb

Cylinder Head
   • 4 Studs
2 Bolts

18 ft/lb 12 ft/lb

Triple Shaft Nut 30 ft/lb
    Top Triple Clamp Bolt 15 ft/lb






PPG Paint Codes
Bultaco Blue Grabber Blue
DBU 2230
Bultaco Silver Crystal Silver Metalic
DAR 34926
Bultaco Red Torch Red
DAR 74013
Bultaco Gray Grigo Chiaro


Air Filter UNI
# NU-3204ST
$27 @ AMS

Fork Seals
35 x 47 x 10.5

Try Honda 350

Rear Sprocket
125 Pursang 46 teeth
250 Pursang 48 teeth
Sprocket Specialist  

Front Sprocket
125 Pursang 11 teeth
250 Pursang 12 teeth


520 Chain
11/46 = ~106 links
12/48 = ~110 links


Rear Brake Shoes
140mm Diameter

EBC 14-833G

Primary Chain for 125 Pursang    
Primary Chain for 250 Pursang    



Q: Engine sounds like marbles rattling around when it idles, but goes away with rpm's
A: Check the primary side flywheel (Lynn Mobley)

Q: Fork Caps leak oil out the breather hole
A: Cut plastic disks and wedge them in the fork springs a couple of inches
    below the top. (Lynn Mobley) or... plug the hole.


2.8mm BTDC (.110")




Basic Motoplat Testing

Bultaco Terry Cable Listings

Mobley's Bultaco Great for Bultaco Parts

Speed and Sport Great for Bultaco Parts

Bultaco ID

Replacing Worn Vintage Fork Legs


Suspension Forum


How Shocks Work


Vintage Bultaco Racing




Respoke Wheels



Works Performance


Bultaco Pursang Center


Track & Trail Super Test: Bultaco 250 1974