Ski Lites · Chop
Ski Lites - 0-1 ft light chop
A spec is filled on 2 of 5 line items and the reasoning on 5. The document behind the figure is named on 2 of the filled specs.
IJSBA and IHRA rules differ, so each line names its rulebook: who runs racing near you.
Treat these settings as a starting point, not a tested setup.
Racing this on the SuperJet (2-stroke)? The SuperJet Ski Lites Tech-Pass Kit asks for every part checked legal for the class in one message.
Conditions this is written for
- Class
- Ski Lites
- Venue
- Chop
- Water
- Light chop, 0 to 1 ft
- Rider weight
- Not stated
- Machines
- Yamaha SuperJet 701 round-nose (1996-2007) · Kawasaki SX-R 800
- Last raced
- Never recorded
- Glass
- Light chop, 0 to 1 ftthis sheet
- Chop, 1 to 2 ft
- Rough, 2 ft plus
Boxed: this sheet's water.
Not to scale.
Drawn heavier and labelled "on sheet": the intake grate, impeller and ride plate, the lines of this sheet that sit on the jet pump. This is where each kind of part sits, drawn fresh from patents rather than from any one maker's pump.
How we know: US patents 8,905,800 (lines 64 to 70 of the held copy), 5,833,501 (lines 67, 91, 93 and 94), 5,520,558 (line 48), 6,705,908 (lines 36, 39 and 89), 6,857,919 (line 194) and 6,523,489 (lines 185 to 187).
Not to scale.
Parts manifest
| Item | Spec | Why | Get it |
|---|---|---|---|
| impeller | no spec Limit: IJSBA 2024, SKL.6.1 · checked against the rulebook on 2026-09-07 · read the rule | In chop under a foot the pump is mostly fed but the load comes and goes over small waves, so pitch has to suit how the engine responds to that, not only steady pull. IHRA 2026 J.18.2 attaches the original-diameter condition to a "Stock class" it does not run, so treat the diameter as fixed under both bodies and confirm with the technical inspector. Options: Solas Concord for the SuperJet 701, 144mm pump: YB-CD-13/17 (also listed as YB-CD-13/17A), YB-CD-14/18, YB-CD-15/19, YB-CD-16/20. For the SX-R 800 in the 140mm pump, Solas lists Dynafly KP-DF-13/22, KP-DF-14/23 and KP-DF-15/24. These are fitment lists, not a ranking. Confirm against Solas's own finder before ordering, since applications are revised without notice. | Price on request Ask about the Solas impeller, Yamaha SuperJet 701 |
| ride plate | no spec Limit: IJSBA 2024, SKL.2.5 · checked against the rulebook on 2026-09-07 · read the rule | In light chop the ski crosses short, small waves at speed, so the plate also shapes how the back of the hull meets them, not only how it sits and turns. IHRA 2026 J.18.1 sets the same 100mm limit but does not say what it is measured from, so measure against the stricter wording if you race both. Trim tabs and hull extensions are out under both: IJSBA SKL.2.7, and IHRA section O read with J.1 and A.2.2. | Price on request Ask about the RIVA Racing ride plate, Yamaha SuperJet |
| intake grate | no spec Limit: IJSBA 2024 SKL.2.4: full-length type, at least one bar parallel to the drive shaft, leading edges radiused, depth below the flat plane of the intake printed as "11.00mm (0.47 in.)", two figures that disagree, so 11.00mm is the one that cannot fail inspection. IHRA 2026 J.18.1: the same type and bar rule, no hazardous edges, 0.47 inches (12.00mm). | Chop under a foot costs the pump its prime less often than 1-2ft chop, though other riders' wakes add to it, so the question is whether how often it happens justifies any depth beyond stock. This shop lists two grates, the Worx WR201 for the SuperJet and the Jet Dynamics Top Loader for the SX-R 800, and neither has been measured against either limit. | No part named |
| pipe | OEM exhaust, unmodified IJSBA 2024, SKL.3.6 · checked against the rulebook on 2026-09-07 · read the rule | Water condition does not change the exhaust line. IHRA 2026 O.2.5 is silent on a cooling line on a stinger with no insert, which IJSBA allows, so under IHRA J.1 do not assume it. A pipe means a different class, IHRA Ski GP3, and even there whether the Factory Pipe listed here qualifies is not yet confirmed. | Not stocked here |
| nozzle | OEM pump nozzle and venturi IJSBA 2024 Ski Lites class document, SKL.1.1 (closed list), SKL.6.1 and the rule numbered SKL.8.2; IHRA 2026 rulebook V.20260603, J.1 and O.5.1. The archive's rulebook reference for the pump nozzle and venturi. | Water condition does not change the nozzle line. Aftermarket nozzles and pump-mounted trim systems fit and are sold freely, but neither is on IJSBA's closed list. IHRA 2026 O.5.1 lets a SuperJet modify its OEM nozzle for angle adjustment and a Kawasaki 800 bore its own, which IJSBA does not allow. | Not stocked here |
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