What causes Carburetor gumming from ethanol fuel sitting on the Suzuki Boulevard S40?

Rough idle, hard start, fuel smell, black smoke Estimated fix cost: $50-$150

What causes Cam chain tensioner wear causing rattling on the Suzuki Boulevard S40?

Cold start rattle that disappears after warm-up Estimated fix cost: $80-$200

Oil streaks on fork tubes below upper seals Estimated fix cost: $100-$250

Known issues to inspect before buying a used Suzuki Boulevard S40. What to check and how much repairs cost.

MODERATE

Rough idle, hard start, fuel smell, black smoke

Fix cost: $50-$150

MODERATE

Cold start rattle that disappears after warm-up

Fix cost: $80-$200

MODERATE

Oil streaks on fork tubes below upper seals

Fix cost: $100-$250

☐Start cold, listen for top-end rattle

☐Check fork tubes for oil residue

☐Rev through full range, no stumbling

☐Inspect air filter and carb boot cracks

Simple reliable single, easy cheap maintenance overall