Tomos A35 / A55 are chain final drive with an automatic two-speed in the cases — not a scooter CVT, and not a belt to the rear wheel. Slap is usually free play, wear, or mounts — confirm before a top-end spend.
What the Tomos guide specifies
- Chain slack about 10 mm free play (up/down); check about every 500 miles — Tomos A35 / A55 guide.
- Clean, lube, adjust; replace hooked sprockets as a set.
- Gearbox: Type A (Dexron) or Type F ATF — low or wrong fluid can add noise and hurt the two-speed clutch.
- Sudden slap after a tip-over: check hanger alignment / engine mounts before throwing a chain at it.
- A35 fill tip from the guide: drain bottom plug, fill through top until fluid weeps from the side level (Phillips) screw — go easy; that screw strips easily.
Don’t mix platform numbers
The maintenance hub lists Puch midpoint free play around ~12 mm — different platform; don’t mix numbers. Always prefer the platform guide + your factory manual.
Related
- Slipping / hanging in first → clutch slip.
- Service rhythm → maintenance hub.
- Identify A35 vs A55 before ordering parts — VIN digits and carb family differ (SHA vs PHVA).