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All 650's Pair valve problems

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May 10, 2021
Riding Since
Hi all,

After some research with some motorbyke workshop, I discovered that the noise (ticking) is from the pair valve system.

Introduction: I bought the bike with 5k miles and MIVV exhaust. The bike had a Power Commander installed, but the old owner sold it before, so I've bought the bike with the MIVV and without the Power Commander previously installed. After some ride and risking a police fine (no catalyst system), I've decided to install the original exhaust (a mechanical did that).

The best motorbyke workshop of all the ones I've seen (here in my country he is very well known) told me that he listen a "roar" in idle, that disappears after 1.5 rpm, when the anti-pollution stop working. But he told me too that is not a problem at all, maybe the old owner do some things to the anti-pollution but "who cares".

Now, can you tell me what engine problems can cause a bad pair valve system? Like, if there is an air leak, what can happened to the engine? Because the mechanical told me that he can check the pair valve when he will change the spark plugs, at 15k miles, and to not be worried at all.

But I have to do other 9k miles before 15k miles! With my daily road, I think I'll get to that mileage in October!

So, what I have to do? Just be calm or fix the problem as soon as possible?
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