Many riders of electric bicycles here are motorcyclists who have lost their licences, with many modified versions of the bikes able to go as fast as 120kmh, retailers told My Paper.
Checks with several shops show that at least two of them offer modification services - even though its operators are aware that it is illegal for motorised bicycles to go faster than 25kmh.
Online listings selling modified bicycles that can travel up to 80kmh can also be easily found. These vehicles are going for between $650 and $2,000.
Anyone found using or keeping an unapproved motorised bicycle may face a fine of up to $1,000 or three months' jail. For illegally modifying a motorised bicycle, a person may be subject to a $2,000 fine or three months' jail.
A Land Transport Authority (LTA) spokesman told My Paper that since 2011, it has imposed heavier penalties on those who use or sell motorised bicycles that do not meet LTA's technical requirements. LTA issued 1,250 and 978 summonses in 2012 and 2013 respectively, and 1,042 summonses last year.
There are no official figures on how many electric bicycles are on the roads here, as such vehicles do not come with licence plates or require road tax. Like conventional bicycles, such riders also do not need a driving licence to own or use one.
According to LTA regulations, motorcycles can go up to 50kmh on roads, and 70kmh to 90kmh on expressways. Illegally modified electric bicycles match these speeds, several industry players say, citing "shops in Geylang" which offer such services.
My Paper called up two retailers - one in Bukit Batok and the other with branches in Geylang, Yishun and Serangoon - and asked if they could modify a motorised bicycle. Both operators replied that they could do so within a week for at least $1,000.
When asked if it was legal to do so, a man from the Bukit Batok store said: "LTA regulations say 25kmh, but if you want to modify to go faster, it's on you. The user is responsible."
Retailers who do not offer illegal modification services say they have noticed this trend among "black sheep operators".
Chris Kuah, owner of A-Tech Bike Supply in MacPherson, observed that about 10 per cent of users modify their electric bicycles.
"Modified e-bikes can go as fast as 80kmh to 120kmh," the 44-year-old said, adding that he sells only LTA-approved vehicles.
"Small (engine capacity) motorcycles can also go up to about 120kmh, so modified e-bikes are as fast as motorbikes, but motorbikes are much heavier machinery and can absorb (greater) impact."
B. T. Ong, who runs Singapore Bike City in Ubi, said that illegally modified electric bicycles can go as fast as 100kmh.
According to him, six out of 10 people who buy motorised bicycles from him used to ride a motorcycle.
"Some of these people had their licences revoked, others don't want to say why they no longer have a licence," the 62-year-old said.
"Sometimes, the certificate of entitlement for their motorcycle expires and they don't have the money to get a new one, so they buy an electric bicycle instead."
Tay Sam Choon, owner of RR Motor in Geylang, has also noticed this trend.
"Thirty per cent of people who buy e-bikes (from us) are those who lost their motorbike licences," the 71-year-old said, adding that he switched from selling motorcycles to mainly motorised bicycles to meet the increasing demand.
When contacted, LTA said that only low-powered models of motorised bicycles approved by it are allowed for use on public roads. All new models must be approved by LTA-authorised vehicle inspection centres.
There were two fatal accidents involving power-assisted bicycles last year, and one each in 2013 and 2012, according to the Traffic Police.
Some are calling for tighter regulation of these vehicles. Amolat Singh, senior lawyer at Amolat & Partners, said that motorised bicycles are becoming an increasing "menace on the roads", adding that "it is practically impossible" to track down the rider in the case of a collision.
He said that the damages may be thousands of dollars if the personal injury is serious or incapacitating.
Mr Singh added: "The potential for serious bodily harm and death cannot be ignored, and the authorities must find a suitable response to mitigate the hazard posed."
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