Q. I have an immaculate Kawasaki KLR650 with a Marvin stainless steel silencer that looks and sounds great.
Marvin does not make a header pipe, so are there any exhaust firms who could manufacture a stainless header pipe to fit the Marvin components?
Neil Brooker, MCN forums
A. There are a few firms out there who can offer a one-off service, but do check the price of an original equipment replacement before you get any quotes, as a bespoke pipe is likely to cost more than a mass-produced part.
The price will also depend on the number of curves needed, so a convoluted pipe for a Honda Magna custom bike is going to cost more than a simple downpipe to a collector box.
Whoever you use will probably need the bike with the exhaust removed, or at least all those rusted nuts and clamps loosened right off (tip: when you buy a bike, new or used, remove, use high-temperature grease and retighten all those nuts and clamps).
The pipe will be either 1.2 or 1.5mm thick, the thicker gauge pipe is more heat resistant, but all stainless pipe goes harvest yellow when it gets hot, or even blue at the cylinders if the jetting is too lean.
Roy at OS pipes in Stafford recommends chrome cleaner and “plenty of elbow grease.” But not Solvol Autosol as that is “too coarse”.
Over time the exhaust will become less susceptible to this as a thin layer of insulating carbon is laid down on the inside, but if it does offend your sensibilities then an annual re-buff by a professional will return them to a mirror finish for £5 or £10 per pipe.
The manufacturers’ standard pipes don’t suffer so much because they are double-skinned, with a smaller internal pipe creating an insulating air gap. This design also allows the designers to spec up “meaty” outer pipes to suit the look of a big-engined bike.
Prices range from £65 to £120 per pipe and most firms offer a seven to 10-day turnaround.
Gibson Exhausts in Romford, Essex: 01708-372122
OS pipes in Stafford: 01889 271818
Predator Exhausts in Welwyn Garden City, Herts: 01707-334090
Quill Exhausts in Lowton, Lancashire: 01942-721744