These guys do good work at very reasonable prices.  They can work on just about any bike and they actually include Pick-up and Delivery within Bangkok.  The service generally takes one week, so if you are  here traveling it may not be the best option for you unless you can arrange your schedule around it.

L.P.R. Service is the official Bike Repair Team for the Bangkok Hash House Bikers (BHHB) and they were previously employed through an upscale adventure equipment and mountain bike shop that had a conflict between the business owners and ultimately closed.   During their time working their they had the opportunity to meet many locals both foreign and Thai and then started their own business when learning of the planned closing.  Since management was closing and not just restructuring, they were kind enough to let L.P.R. have access to their customer base and even helped them get involved with the BHHB.

Their Pick-up/Delivery Days are Tuesdays and Thursdays, but you can reach them just about any time via phone or email.

Mechanic Names:  Khun Odd and Khun Knot

Phone numbers:  02-427-1537, 081-205-4206, or 081-459-4206

Email:  knot353@yahoo.com