XR650R torque with exhaust change

Does swapping the stock header/pipe on an XR650R with an aftermarket

one (stainless header, aftermarket exhaust) really effect the low-end torque to a significant extent? I've read it does. Thanks for input!!!

You gain much more in overall performance than what little bit you might lose...just get a pipe like an FMF where you can select different end caps if you are really worried about it..new pipe and can makes the R a totally different and better bike

I recently installed a full CRD exhaust system, it's not made anymore, I just happened to find the headers and pipe online. It uses an oversized header and a long, quiet endcan (~91-94db). As my particular endcan is more restrictive than the usual endcan that you will find with other full systems, the results will vary. More open endcans should lessen the bottom even more, while adding even more to the top.

Performance wise, it does seem to soften up the bottom end a bit. However, the 650R has SO MUCH bottom end, even with loosing a bit, it still has plenty. Here in NW Florida, alot of riding is in thick, soft sand. I found that the bike would still easily lug/torque it's way through with no problems. I'm running taller dual sport gearing also, 15/48.

The big difference is in the top end. With the stock headers, the bike revs up fast and the power flatens out in the top end. With the oversized headers, the bike seems to pull softer at first but then it keeps pulling harder and harder as the RPM's increase all the way to the rev limiter. In terms of numbers, I would say the power drops off at ~6000RPM with the stock headers, while the power keeps climbing up to ~8000RPM with the oversized headers. Basically you are just moving the peak HP to a higher RPM range.

I've got mixed feelings about the oversized headers. The extra top end pull is exhillarating to me after using the stock headers for so long. At the same time, I kinda miss the bottom end snap. For primarily street use, or extended high speed desert use, oversized headers would be perfect. For slower riding, trails and such, the stock headers are the way to go with their off idle, stretch your wrists torque.

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