AHRMA MX Tech Inspection

Vintage-class shock travel guide

The following chart is used by AHRMA motocross tech inspectors as a quick method of determining maximum rear suspension travel. Inspectors may also choose to follow the procedures listed in rule 11.2(a) of the AHRMA Handbook. The chart will be updated from time to time as more information is gathered. For questions or suggestions about additions to the chart, contact one of the national motocross tech chiefs or Motocross Rules & Eligibility Committee members listed in the handbook.

Brand & Year Model Maximum visible
shaft length*		 Comments
AJS
1969-74 250/370/410 3½ inches Standard swingarm (over axle)
2½ Moved up swingarm
American Eagle 125/250/360/405 3½ Stock swingarm
Bultaco
1967-73 3¼ Stock swingarm
Metisse Model 11 3½ Stock swingarm
1975 250 only 2½ Straight up and down
Can-Am MX-1 3 Standard swingarm
Cheney
Early 3½ Nickle plated (over axle)
Late ? Moved forward (check)
CZ
1968-73 125/250/360/400 3½ Stock frame & swingarm
1974 Red frame 3½ Stock frame & swingarm
1975 Falta 2¾ Stock frame & swingarm
Greeves All 3½ Stock frame & swingarm
Hodaka 125 3¼
Honda
1973-74 CR250 3¼ Stock setup
1974-75 CR125 3¼ Stock setup
125 2¼ With Redline swingarm (always check)
Husqvarna
1968-74 3½ Without Mag swingarm (pre-'74)
1968-74 3 With Mag swingarm
1968-74 2¾ With Profab swingarm (straight up & down; always check)
Kawasaki
1973 F11M & F12M 3½ All stock frame & swingarm
1974 KR250 & KX450 3½ All stock frame & swingarm
1974-76 KX125 3½
1975-76 KX250 & KX450 2¼ "Forward mounted" (always check)
Maico
Pre-1974½ 3½ Stock frame
1974½ 2½ No holes in frame mount; 1 mount on swingarm (rare)
1975 2¼ Holes in frame/middle lower mount (always check)
Ossa
1967-72 Stiletto 3¾ Over axle
1974 Phantom 125/250 3½ Allow swingarm stock part
Penton/KTM
1973-74½ Check Middle lower mount (always check)
Rickman All 3½ Over axle
Sprite All 3½ Over axle
Suzuki
1971-74 TM 125/250/400 3½ Stock setup
1975 TM 125/250/400 2½ Straight up & down shocks
Trackmaster All 3-5/8 Nickle plated
Yamaha
1972-74 MX250/360 & SC500 3½ Stock setup
DT/RT2 MXes 3½ Stock setup
YZ250/360 3½ Stock setup

*Note: All measurements include one-third the thickness of the rubber bumper.

  • All motorcycles must clear/pass tech inspection. Those with forward-mounted rear shocks will/should be check even closer each time.

  • All motorcycles will have no more than 7 inches of front wheel movement and no more than 4 inches rear wheel travel. This is not shaft travel.

  • "Travel limiters" are available for $2.00 each at every AHRMA MX event.

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