Most certificate of entitlement (COE) premiums ended higher in the latest tender on Wednesday.
Cat B, for cars above 1,600cc or 130bhp, rose by 2.7 per cent to finish at a four-month high of $80,710.
Open COE, which can be used for any vehicle type but ends up mainly for bigger cars, climbed 3.8 per cent to end at $82,000, also its highest since November.
The only exception was Category A, for cars up to 1,600cc and 130bhp, which dipped by 0.3 per cent to $76,999.
Motor traders said last Friday's launch of the new Honda Odyssey contributed to demand for Cat B COEs, as did other new models such as the BMW 2-series Coupe.
Volkswagen Singapore general manager of sales Daniel Chong said: "Cat B has gone up, but the segment is still not all that strong. I think all the big boys in the market are determined to secure COEs for whatever bookings they have on hand."
High prices have cooled demand for Cat A cars, offset partly by demand whipped up by last Wednesday's launch of the new Mazda3.
Separately, dealers rushing to clear stock before a new emission standard kicks in may also be keeping COEs up. From next month, petrol cars must meet the more stringent Euro IV standard, up from the current Euro II standard that has been in place since 2001.
Meanwhile, commercial vehicle COE rose by 6.5 per cent to finish at a five-month high of $56,302. Industry watchers also attribute that to the launch of the Mercedes-Benz Citan compact van.
Mr Ron Lim, general manager of Nissan agent Tan Chong Motor, said: "They don't need to sell a lot - just 20 to 30 units will already make up close to 10 per cent of the quota."
The premium that posted the biggest jump yesterday was motorcycle COE. In its eighth consecutive rise, the COE shot up by 14.3 per cent to end at $4,001 - its highest since December 1995.
Singapore Motorcycle Trade Association president Wilson Phoon put this down to a smaller COE quota.
"The supply of motorcycle COEs is 30 per cent lower than before," he said, adding that the new Euro III emission standard which will affect two-wheelers from October has also triggered "some panic buying".
Most motocycles here are merely Euro I-compliant.
Here are the latest Certificate Of Entitlement results from Wednesday's bidding exercise:
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