Before anyone starts with the namecalling and laughing at my questions - I admit to being mechanically challenged

Anyway - could someone tell me where the cat is located? Exhaust is coming out both my pipes, so can't be there..? If I buy 2-1 cans, will I need something else to get rid of the cat?

And also, being a single cylinder, how come two pipes are coming out of it?

Lastly, I was thinking to get a Power Commander in due time, and see that it should be used together with an O2 eliminator. Is this the plug-thing on one of the pipes under the front of the bike?

Assuming this is a Tenere with the stock exhaust, the cat is somewhere inside the big box under the seat. If you've got the Yamaha Akra cans, they're in the 'bulge' in each link pipe just in front of the silencer.

The reason there are two pipes coming out of the engine is something complicated to do with exhaust tuning (increased gas velocity over a single large pipe?) which someone else can probably explain better than me.

The reason there are two pipes/outlets coming out of the big silencer box on the stock system is to make the bike look symmetric, nothing more.

If you buy an aftermarket 2-1 system, you will remove the big box under the seat, and therefore the cat.

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I spent a lot of money on travel and racing motorcycles - the rest I just squandered.

XT660Z - Commuter, Adventurer...Racer?

www.dashmoto.net

Other bikes >> MT-03 / CG125BR-J / ER-6F
Departed >> ZXR400L3 / EC300 / DR-Z400E / DR800S / GPZ500S / GS400

Great stuff, I'll lose the cat either way when putting on slip-ons then.

By the way, would I need a can specifically designed to replace two cans, or would any kind do? I mean, is the can the same, and the linking pipe the only difference?

By the way, is there a common concensus as to which exhausts give the best performance gain?

When we consider that all the aftermarket exhausts are just straight through cans with no catalytic converters and intrisicate restrictions inside, at the end of the day the power you get from them depends on the diameter of the link pipes, the cans themselves and that of the outlets and even the inclination of the link pipes makes a difference, the more direct and less angled is the exhaust flow the higher will be the power response.

Oh and it makes absolute no difference if they are made of S/Steel, Carbon or Titanium, except for weight and looks.

Have you looked at our sponsored MTC Cans on this link: http://www.xt660.com/site/node/340

ok this is what the exhaust looks like inside and you can see how i took it out. i also derestricted the pipe by drilling the main box so i feeds direct into the secondary boxes ie the outlets. bit noisy but not too bad. everyone on the recent ride thought it was fine.

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check out www.redbikejohn.com for all the latest race reports from the CHEC and enduroland.

Whoa. Thanks for the pictures!

Looks pretty restricted.

any noticeable improvements?

Well I fitted a fuel mod (home made to Kev's spec) and also took the snorkle off are the same time so hard to pin down to one mod. however there was a noticable improvement in fuel economy. I get 60 mpg now each time I fill up.

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check out www.redbikejohn.com for all the latest race reports from the CHEC and enduroland.

I noticed this when I put the MTC can on. I put it down to being able to run at lower revs (with the MTC can you get more low down, usable power). Maybe, after your comment it's more to do with the bike not expelling energy on forcing gasses through a ceramic sponge, and therefore reducing the fuel needs.

Or maybe both!

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Never underestimate the power of stupid people in large groups.