To develop full power, the expansion chambers need to be "fatter" than the stock Honda pipes, and also shorter.

This means that any race pipe you fit will be too wide to fit inside the stock (or stock pattern) bodywork.

Some aftermaret designs, notably TYGA Performances GP250 fairing and Jha's latest range, will accommodate race pipes as it was designed around them.

I believe TYGA pipes and HARC Pro pipes are the worst for fitting because they are the fattest (i.e. most developed!) pipes on the market today. TYGA's GP pipes were only released 18 months - 2 years ago, and were built from scratch using the latest TSR software available at the time, so you won't find much better performance! A slight adjustment of the bodywork to fit pipes like these is well worth the effort, and will transform the bike in both power delivery and looks!

Andy.
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