# Damiki Umpa 40 BFS: the 4 cm popper that blows up the surface > 4 cm, 2.8 g and a generously cupped mouth - how to cast and work the Damiki Umpa 40 on BFS gear to draw topwater blowups from bass and perch. - Source : https://carnafish.com/en/leurres/damiki-umpa-40-bfs-topwater-popper/ - Language : en-US - Updated : 2026-09-22 ## Spec sheet - Brand : Damiki - Model : Umpa 40 BFS Topwater Popper - Type : Compact topwater popper - Target species : Bass, Perch - Size : 4 cm / 1.6 in - Weight : 2.8 g / 0.1 oz - Running depth : strictly on the surface - Retrieve speed : slow, sharp twitches broken up by long pauses - Action : widely cupped mouth that throws water and creates a loud surface disturbance - Rigging : loop knot or small snap, BFS or light spinning gear, stock trebles worth checking - Colors : natural olive back in clear water, pearl white under overcast skies, chartreuse in stained water There are August mornings when the surface is glass and any 10 cm lure scatters everything swimming within three metres. That is where size changes everything: a 4 cm popper makes a disturbance loud enough to be heard and small enough not to spook. The Damiki Umpa 40 is built for exactly that window, and the name says so — BFS, for ultra-light casting setups. ## Four centimetres, 2.8 grams, and the whole casting problem The numbers Damiki publishes are clear: **1.6 in, so 4 cm, for 1/10 oz, so 2.8 g**, with the class listed plainly as topwater. Those three figures drive the entire approach. At 2.8 g you are below the comfort threshold of most standard casting combos, which start struggling under 5 g: the spool will not start, the cast dies at eight metres, and the wind does the rest. Hence the **BFS** tag, Bait Finesse System: casting reels with lightened, finely machined spools, sometimes with a dedicated magnetic brake, able to throw featherweights without a backlash. Damiki stresses the body's aerodynamic construction, and you can see it in the profile — a teardrop tapering sharply to the rear, which cuts drag in flight. That is a real difference from stubby little poppers that tumble in the air and land any which way. If you do not own BFS gear, the lure casts perfectly well on a light spinning setup with thin braid, something like a 2 m light-power rod with 8/100 braid. You lose a little placement accuracy and gain a lot of ease. Do not force it on a standard baitcaster: the ratio between lure weight and spool inertia is not on your side. ## A cupped mouth that makes more noise than its size suggests The technical point the maker emphasises is a **generously cupped** mouth relative to the lure's size. In the photo the cup takes up almost the whole front face, with a bright red interior. A cup that open catches a lot of water on the smallest twitch and throws it forward with a sharp sucking crack, instead of the muffled plop of a timidly cupped popper. That detail matters more than you would think on a lure this size. A poorly cupped mini popper does not carry: the fish cannot hear it beyond a few metres, and you lose the whole point of topwater fishing, which is calling fish in from a distance to one precise spot. Damiki states outright that this commotion is there to pull up fish holding under structure or sitting in shady pockets. The maker describes the profile as an imitation of a wounded baitfish or a fleeing prawn. Both readings hold depending on how you work it: tightly spaced twitches give a panicked baitfish, widely spaced single pops look much more like a prawn skipping away in bursts. > In fine topwater work it is the silence that sets up the bite, not the noise. After each plop, count three full seconds while you watch the rings spread. Nine times out of ten the bite comes during the pause, not during the pop. A popper worked non-stop is a popper you reel back empty. ## Where and when to use it The best windows are the two hours after first light and the hour before dark, when the low angle hides the angler's outline and the bait rises. In full sun the small popper only stays worthwhile in the shade: under a dock, against a wooded bank, alongside a laydown. The targets are places where a fish can ambush from under a ceiling: weed edges, scattered lily pads, matted algae with holes in it, dock pilings, emergent rock. The lure's size lets you work one-square-metre holes you could never fish with a 10 cm popper without fouling the weed on the first twitch. Perch are a serious second customer in Europe at this size. A school of perch feeding on the surface over a shallow flat responds very well to the Umpa 40, with shorter and more tightly spaced twitches than for bass — perch chase and hit a lure that is fleeing, much less one that is resting. ### The classic mistake Setting the hook on the sound. You hear the blowup, you see the explosion, you set within the second — and you rip the lure out of the mouth of a fish that had not yet closed on it. On a popper, and all the more on a small model with fine trebles, the rule is to wait until you feel weight in the rod, then set sideways and without violence. A big vertical sweep on a 2.8 g lure throws more fish than it hooks. ## Hooks and leader Damiki lists sticky sharp trebles as standard, chosen to improve hookup ratios. The sample photographed is bare: both hangers, belly and tail, are empty in the photo, which is the usual catalogue presentation rather than any indication that the lure ships unarmed. On a popper of this weight, treble quality is not a detail. A treble that is too heavy sinks the tail and kills the popping action; one that is too fine bends open on a good fish dragged out of weed. If you replace the stock hardware, match the original weight exactly and check the float in a bucket before you fish: the lure should sit slightly nose-up, not flat. At the business end, a loop knot or a small snap lets the nose pivot freely on each twitch, which noticeably increases side-to-side travel. A tight knot locks the axis and turns the popper into a cork that hops straight forward. Fluorocarbon leader in 20 to 24/100, fine enough not to choke the lure, strong enough to drag a fish out of a cluttered bank. For a Japanese popper of comparable size, the [Megabass Pop-X](https://carnafish.com/en/leurres/megabass-pop-x/) remains the historical benchmark of the genre, with a more side-to-side action. The [Bassday Crystal Popper](https://carnafish.com/en/leurres/bassday-crystal-popper/) plays on a longer body, and the [6th Sense Splash Back](https://carnafish.com/en/leurres/6th-sense-splash-back-topwater-popper/) on a noisier disturbance, useful when there is chop. ## Colour by light - **Clear water, first light**: the natural olive back of the sample photographed, with its holographic eye. Seen from below the silhouette stays subtle and the eye supplies the only focal point. - **Overcast skies or lightly stained water**: pearl white. This is the colour that reads best against a grey sky seen from below, and it stays visible to the angler at thirty metres. - **Stained water or midday feeding**: chartreuse. Less natural, but in fishing where the fish comes up on sound before it looks, visibility beats realism. A popper only works if you land it on the right square metre, and that is decided before the cast. That is what [CarnaFish](https://carnafish.com/en/) is for: a photo of the spot, and the app suggests the zone to cover and the lure type suited to the day's conditions. To sharpen your approach on perch spots, our [guide to perch fishing with lures](https://carnafish.com/en/blog/peche-perche-leurre/) covers the other families worth keeping in the box. ## Key takeaways - Figures confirmed by the manufacturer: 4 cm for 2.8 g, classed as topwater. - The weight calls for BFS or light spinning gear; a standard baitcaster will not cast 2.8 g properly. - The generously cupped mouth is what gives this small lure a useful acoustic range. - The bite comes during the pause: wait until you feel weight before setting, sideways and without violence. ## FAQ ### Do I really need BFS gear to fish the Umpa 40? No, but it is the most comfortable option. A light spinning setup with thin braid casts 2.8 g without trouble. A standard baitcaster not built for featherweights will give you short casts and backlashes. ### How long should the pause between pops be? Three seconds minimum in calm water, longer if the fish are inactive. The basic rule is to let the rings dissipate before twitching again. Most bites happen during that dead time. ### Is this popper any good for perch? Yes, it is one of its best uses in Europe on schools feeding at the surface. Just shorten the interval between twitches compared with bass — perch respond better to prey that keeps fleeing rather than stopping. ### Are the stock hooks good enough? Damiki lists sticky sharp trebles as standard. If you replace them, keep the same weight without fail: a heavier treble sinks the tail and removes the popping action entirely. ### Why does my popper hop straight forward instead of pulling sideways? Almost always the knot. A tight knot directly on the ring locks the lure's axis. Switch to a loop knot or a small snap, and twitch with the rod low rather than high. ### Can it be fished in the middle of the day? Yes, but only in shade: under a dock, along a wooded bank, against a laydown. In full sun over open water the best windows remain first light and the last hour before dark. --- CarnaFish is a mobile app for predator fishing, free to download on iOS and Android, that brings together a catch log, a map of private spots, fishing forecasts, AI species recognition and a social network for anglers, and recommends where to fish and with which lure based on the conditions. To cite this content, mention “CarnaFish — carnafish.com” and link the source page.