Open Monday through Friday, 11 a.m. to 11 p.m.; Saturday and Sunday, 4 p.m. to midnight, AE, BA, CB, D, MC. Reservations.

Food: Don't stray far from the crab and prime rib

Style: Log-cabin modern

Price: Main courses at dinner $5 to $10

If Happy Days ever decides to do a show about the Fonz twenty-five years after, Berk Motley's Sirloin Room is the place to do it. Preferably on a Saturday night. It will be difficult to clear out the faithful in order to have room to film, but it will be worth it.

The enormous log cabin, shiny enough to have been urethane-coated, and outfitted with a slick array of black leatherette banquettes and red shutters, is said to have once been a strip joint. But, in the last couple of decades since exbandsman Berk Motley took it over, it has gone straight - after a fashion. It is not quite as straight as the introduction to the menu implies ("one of Maryland's outstanding restaurants," "gracious atmosphere of colonial decor," "cocktails from the hands of our master mixologist"). But it is queens celebrate their fortieth birthdays, and bowling clubs gather for their Saturday nights on the town, staying late enough to blush or guffaw at Motley's show.

Let's get right to the show before we go any further, in case you want to be sure to see - or not see - it. First, there is a small band playing big-band sounds, which somehow come out sounding like skating rink music. Throughout the evening, leisure suits and cowboy shirts, mini-skirts and platinum wigs bob and whirl to "Dancing in the Dark" and "I Only Have Eyes for You" between the clams a la maison (a kind of thickened, pureed Manhattan clam chowder in shells) and iceberg lettuce salad with the onions on the side (in case you forgot your Sen-Sen). Then comes Berk Motley himself, behind a barricade of clarinets and saxophones, probably having spent the day in an adult bookstore gathering material for his show. He tells a few jokes of the "My wife is so ugly that . . ." variety, and plays his saxophone - extremely well. He goes on to other jokes either too risque or too stale even to refer to here, and plays three clarinets at once. He sings a few happy birthday, mercilessly embarrasses anyone who happens to have a ringside seat, plays a few more songs, and eventually plays two clarinets at the same time while standing on his head. It gets worse, but any more detail would lose the faint-hearted among my readers. Suffice it to say that somehow Motley emerges seeming like an awfully likeable guy who happens to tell the kinds of jokes that wouldn't survive long if there were a gong around, but he sure plays a mean clarinet. If that doesn't sound like your kind of entertainment, you can go on a weekday, when the only entertainment is Muzak.

The food is about the same as the show: sometimes awkward, sometimes embarrassing, supposedly glamorous but certainly unsophisticated, yet somehow likeable after all.

Maybe it's the drinks that make the difference. That "expert mixologist" is, indeed. A grandmotherly sort in a white [WORD ILLEGIBLE] polyster pants, she operates within a [WORD ILLEGIBLE] leatherette bar the size of a swimming [WORD ILLEGIBLE] we having here?" she sweetly inquires. And if [WORD ILLEGIBLE] knows what he'd doing, he orders a bloody mary [WORD ILLEGIBLE] whiskey sour; they are so famous that Jody - the [WORD ILLEGIBLE] - sells her special mixes by the quart. The secret to the [WORD ILLEGIBLE] marys, she says, is in mixing ahead and half-dozen voices with the vodka, and only adding the tomato juice at the ast minute. The she might describe the frothed and blended drinks she made for her friend's shower, and end up complaining that Mr. Motley never gets around to buying her a blender so she can really mix up some great drinks. By then you may have learned that drinks are $1.60, $1.75 with cream, and the plantation punch is too sweet.

Bloody marys aren't enough to keep a restaurant going for decades, so fortunately the kitchen has some good tricks, too. Order the crab imperial or crab cakes, both of which are rarely prepared with respect around Washington, and both of which are done well at Motley's. In such dishes, doing them well means not doing much to them, just lightly mixing crab with enough cream sauce of mayonnaise to barely hold it together, and baking or frying it, as the case may be. That's how they are done at Motley's; the crab cakes are crusty and taste of little but fresh crab, and the imperial is moist and nearly all crab. Pork chops are cooked with the same philosophy: big, thick, pale chops don't need any mucking up.

Everyone besides me seems to go to Berk Motley's for the roast beef. With all the menu's claims of its being the finest beef and personally selected and aged to perfection, its most obvious virtues are its size and its price. The $6.95 version is enough to impress anyone who hasn't eaten in three days; the $8.95 portion I hesitate even to contemplate. As the saying goes, it is fork-tender. But it is hard to tell about the flavor, which is unfortunately drowned in an overwhelming brown slosh. Two attemps convinced me that is was impossible to obtain the roast beef either rare or without the juice that upstages it. That shouldn't stop you from trying.

Don't mess around trying to order much else. Appetizers and desserts are serviceable, but you don't really need them with the big bowl of iceberg lettuce salad that precedes the main course and the little scoop of cheese spread that sits on the table. As for the foiled baked potatoes or steak fries, and canned-tasting vegetables that accompany dinners, they sort of fill out the plate and fill up your crevices. If you are still hungry, venture into the French-fried onion rings, which are fresh and crisp and worth the bother. If you get too involved with things like colonial shore dinners and surf and turfs, you may be asking too much. Keep it simple, and a hearty, basic dinner with a drink wont' cost you more than $10. Along the way, you'll learn the real meaning of "a motley crew."