To add to David's post, last weekend I made a trip to KL to take a look at a few bike shops. Here's what I saw.
First visit was to 
KCM SuperBike (No. 17, Jalan  Sri Permaisuri 8, Bandar Sri Permaisuri, 56000 Cheras, KL Tel 03 9173 9435). From the airport this was easy (here’s the .pdf 2015 
Klang Valley Rail Transit Map).  Take the No 7 KLIA Transit to Bandar Tasik Selatan (light blue on the  map, not the purple No 6 KLIA Express). Change to the No 4 LRT to Sentul  Timur (brown on the map. You have to go out of the KLIA station and  follow the walkway to the LRT station nearby). For KCM, get out at Salak  Selatan station two stops down the line. From there take a taxi or find  the opposite (south) entrance to the station. KCM is approx. a five  minute walk.
KCM SuperBike, Kuala Lumpur
On arrival at KCM, I found a range of new and used motorcycles both for  sale and under the spanner. Smaller bikes included 200-400cc Kawasaki,  Honda, and KTM’s (love the 390cc KTM’s) and some large capacity bikes  including a Kawasaki 
Versys 1000 and an 
MV Agusta Brutale 800.   In the workshop at the back of the store was a variety of bikes both  big and small and a rather damaged sportsbike which appeared to have  low-sided on a wet corner. Outside the shop was a range of small bikes  for sale.
What’s striking about motorcycle shops in KL is they sell everything  from 125cc to 1000cc whereas in Thailand motorcycle shops sell either  100cc-135cc Honda/Yamaha/Suzuki or “big bikes” of 250cc and up.
 Venturing upstairs to the clothing and accessories floor there was a  collection of generic “Japanese” lightweight mesh jackets, some pants  and boots, and an assortment of accessories. I would say more  accessories, such as lights and grips to sprockets and fuelling modules,  than clothes. Some small projector headlights suitable for a motorcycle  caught my eye.
KTN S 125 in Kuala Lumpur
After leaving KCM Superbike I turned right and walked down the street  to where some shops were selling small bikes and accessories. Honda,  Yamaha, Vespa, that sort of thing. As I walked by a retro cafe racer  styled 125cc caught my eye. Made by 
KTN. That’s right, 
KTN not the Austrian manufacturer 
KTM. Got to love the stickers, “GP125″ and the Union Jack. Actually, it’s 
Made in Malaysia.
 It was time to find some more bike shops. I had read there were a few  within 2-3km of the LRT station at Sentul. This is on the north side of  Kuala Lumpur so to avoid the traffic it’s quickest to take the train.
 From KCM turn right out of the shop, proceed to the end of the row of  shops approx. 50m. Turn right and walk due north(ish!). You should be  able to see Salak Selatan station roof. Pass through the small bus  terminal to the station to re-embark on the No 4 line towards Sentual  Timur. I got out at Sentual (Bandar Baru Sentul).
It was after arriving at the station that I was lucky. Turned down by  one taxi driver, the next was one of those 1 in 100  taxi  drivers, the ever helpful Mr Jasbir Singh Gill (019 6629 566).  After  some gentle enquiries he took me on a tour of the local motorcycle  shops. He waited for me while I visited the stores. And he called his  son in law to email a list of motorcycle shops in KL. Outstanding.
 First, we went to 
Sunny Cycle  (37, Jalan Pahang (Titiwangsa), Setapak 53000, tel 03 4021 1161 /  6611), recommended by David in the post above. This was the second bike shop on my list after KCM. It was  Saturday afternoon and Sunny Cycle was busy. I entered via the workshop,  mainly to see the range of bikes that was being worked on. BMW’s, both  sport and touring, Ducati, and Kawasaki were in evidence. Road bikes and  race bikes. It looked good.
The Sunny Cycle workshop on a busy Saturday afternoon
A door to the left took me inside the shop proper where there was an  impressive collection of motorcycle clothing including garments from  Held and Clover in Europe. While Held are famous for their leather  motorcycle gloves, Clover isn’t well known outside of Italy. From the  point of view of a garment designer, I admire their product since they  are one of the few companies to design to the European standard for  “Personal Protective Equipment for Professional Motorcycle Riders” EN  13595. If you want 
verifiable top quality, this is the standard to look for.
Sunny Cycle showroom, Kuala Lumpur
After Sunny Cycles, Jasbir suggested we visit 
CBK Motorsport. They are Malaysia’s “
Kawasaki MX World One Stop Center”  housed in a four storey building on the corner of a street junction  (No. 373, Batu 2, 3/4 Jalan Ipoh, 51200 Kuala Lumpur). You can’t miss  the building; it’s painted Kawasaki green.
CBK Motosport Kawasaki MX Center Kuala Lumpur
Inside the store CBK offer a large range of MX bikes, clothing, and accessories. If you are looking for motocross gear this is the place to come.
After CBK it was a short journey to Jalan Sentul where there is a large  number of motorcycle accessory shops. First, I wanted to visit 
Kedai Motosikal, part of 
AH Hong Motor.
Kedai Motosikal, Jl Sentul, Kuala Lumpur
The observant reader will immediately notice a white No 27 “classic”  bike on the pavement. It is another classic style KTN.
 Kedai Motosikal stock a wide range that on my visit included BMW GS  adventure bikes, a Honda Fireblade SP, 390cc KTM’s, some Kawasaki’s, and  lots of small Honda, Yamaha, and Vespa bikes.
BMW GS at Kedai Motosikal
The workshop was divided into two; a shop unit for servicing small  bikes, and a large area in the main shop for servicing big bikes.
Kedai Motosikal Big Bike Service Area
Judging by the illustrated service posters on the walls they are a major  Yamaha service center. As you can see below, they are a friendly lot.
Kedai Motosikal, Sentual, Small Bike service area
Before heading back to the taxi I wanted to visit the long row of  motorcycle accessory shops that run down Sentul Road after the Police  Station. If you can’t find what you need here, its not available in  Malaysia.
Motorcycle Shops in Jalan Sendul, Kuala Lumpur
NHS Sport Bikers, UMA Racing, Racing Boy, and Kedai Motosikal / MotoZone  were just the beginning as the motorcycle shops stretched over a couple  of blocks. It was here that you can find every manner of spare parts  for old and new bikes as well as some bikes themselves.
Original Carburettors Sentul Road Kuala Lumpur
The range of parts was impressive. This photo of new carburetors was  just part of a much larger display. I’m not sure if RM280 is good value  for a Honda Wave 125 carb but it might be quite handy to know that you  can buy new carbs here if you have a pre-fuel injection bike.
I dodged in and out of a few shops to see what they had. There wasn’t  much in the way of clothing though one shop had a good range of helmets  (Shark, HJC, etc). Cheap rear shocks, HID light systems, tyres, and all  manner of hardware predominated.
Petronas Race Bike
The last bike in the last bike shop I saw  was this Petronas racebike. Was it one of seventy-five legendary FP1  three cylinder 899cc bikes destined to obscurity after the FIM rule  change to 1000cc in 2003? Or was it a Yamaha R1 in drag? Next time I go  back, I’ll have to investigate. It seemed like a fitting end to a day  full of motorbikes both small and large.
My thanks to Mr Jasbir Gill for getting me to more motorcycle shops in one day than I thought possible.
Contacts:
Mr Jasbir Singh Gill (019 6629 566). Taxi service, day booking, city tour, airport booking. Highly recommended.
CBK Motorsport No. 373, Batu 2, 3/4 Jalan Ipoh, 51200 Kuala Lumpur.
KCM SuperBike, No. 17, Jalan  Sri Permaisuri 8, Bandar Sri Permaisuri, 56000 Cheras, KL. Tel 03 9173 9435. Sherlyn Lee.
Sunny Cycle, 37, Jalan Pahang (Titiwangsa), Setapak 53000, KL. Tel 03 4021 1161 / 6611.  Jeremy Oh.
(There is a longer version of this post with a little extra local color on the 
Assero Gear blog.)