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Hi allDoes anyone know if a NZ new, 2000 F650GS will have a catalytic converter fitted in the exhaust or not?ThanksTracy
The left exhaust pipe is a dummy and contains the cat.
Yip. But you can replace it with a dummy tool kit also. 😀
If I'd go through that trouble, I'd use a real tool kit 😀
The bike comes with a toolkit 😡 You can put anything in that compartement if you want to. 😀
The left exhaust pipe is a dummy and contains the cat.
Oh. So what do folk do to get rid of the little blighter? Aside from going the rote of an aftermarket system??CheersTracy
Nothing, save the environment. It's already on the bike, so removing it and ditching it is worse than never having had one, in my opinion. Think globally act locally.
The left exhaust pipe is a dummy and contains the cat.
Oh. So what do folk do to get rid of the little blighter? Aside from going the rote of an aftermarket system??CheersTracy
The 650 is the only bike in BMW range that has the Cat inside the exhaust canister itself (and it's on the left hand side of the bike as you sit on it). For the rest of the range, the Cat sits between the header pipes and the exhaust system so replacing the exhaust with an aftermaket pipe like a Remus or Akrapovic is not going to be a problem environmentally speaking. I've done this with my HP2 and geez it sounds good.On my Dakar, I've taken the OME exhausts off and replaced with a single Staintune unit. I did this for two reasons; a) it reduces wieght, by about 5kgs; and b) mid range performance is a bit better, which is what you want for adventure riding.If your not looking at replacing with an aftermarket exhaust then the only other option is to rip open the OEM and remove the Cat (not a recommended move and probably not a very good look I'd have thought, but each to their own).You do need to decide though why you are doing it. A catalytic converter is just a device that treats the exhaust before it leaves the engine and removes a lot of the pollutants now being attributed to global warming etc. etc. (different debate so let's not go there). Legislation in Europe is primarily responsible for all BMW (and other Euro brand) motorcycles being equipped at manufacture with catalytic converters these days. The GS is equipped with a three-way catalytic converter. "Three-way" refers to the three regulated emissions it helps to reduce -- carbon monoxide, VOCs and NOx molecules. The converter uses two different types of catalysts, a reduction catalyst and an oxidation catalyst. Both types consist of a ceramic structure coated with a metal catalyst, usually platinum, rhodium and/or palladium. The idea is to create a structure that exposes the maximum surface area of catalyst to the exhaust stream, while also minimizing the amount of catalyst required (they are very expensive).The reduction catalyst is the first stage of the catalytic converter. It uses platinum and rhodium to help reduce the NOx emissions. When an NO or NO2 molecule contacts the catalyst, the catalyst rips the nitrogen atom out of the molecule and holds on to it, freeing the oxygen in the form of O2. The nitrogen atoms bond with other nitrogen atoms that are also stuck to the catalyst, forming N2. The oxidation catalyst is the second stage of the catalytic converter. It reduces the unburned hydrocarbons and carbon monoxide by burning (oxidizing) them over a platinum and palladium catalyst. This catalyst aids the reaction of the CO and hydrocarbons with the remaining oxygen in the exhaust gas. The third stage is a control system that monitors the exhaust stream, and uses this information to control the fuel injection system. There is an oxygen sensor mounted upstream of the catalytic converter, meaning it is closer to the engine than the converter is. This sensor tells the engine computer how much oxygen is in the exhaust. The engine computer can increase or decrease the amount of oxygen in the exhaust by adjusting the air-to-fuel ratio. This control scheme allows the engine computer to make sure that the engine is running at close to the stoichiometric point, and also to make sure that there is enough oxygen in the exhaust to allow the oxidization catalyst to burn the unburned hydrocarbons and CO.So, if the environment is not your primary concern, unbolt your exhaust and part with it - the catalytic converter is inside. The amount of noise you get will depend on the pipe your replace the original with, most manufacturers of aftermarket pipes give you a dB rating – usually around 88 or thereabouts with some for of restictor so as to keep you legal on the road.Fuel consumption should not change a lot as the oxygen sensor mounted further forward on the header system is still using information to control the fuel injection system and the amount you burn.Hope this heplsGarry
By the way, one reason I got the HP2 (apart from being such a wicked machine) is that I get to keep the Cat even though I've replaced the exhaust with and Akrapovic, something I could not do with the Dakar without losing the Cat. I do have an environmental bent. The main by-products of combustion are:Nitrogen gas (N2): Our atmosphere is 78 percent nitrogen gas, and most of this passes right through your engine.Carbon Dioxide (CO2): A harmless, odourless gas composed of carbon and oxygen. It is also a greenhouse gas that contributes to global warming.Water vapour (H2O): Another by-product of combustion. The hydrogen in the fuel bonds with the oxygen in the air. These three emissions are mostly harmless, although carbon dioxide emissions are believed to contribute to global warming. However since the combustion process is never perfect, other more harmful emissions are produced in the process.The three main regulated emissions, and also the ones that catalytic converters are designed to reduce, are:Carbon monoxide (CO): A colourless, odourless gas. It is poisonous and extremely dangerous in confined areas, building up slowly to toxic levels without warning if adequate ventilation is not available.Hydrocarbons or volatile organic compounds (VOCs): Any chemical compound made up of hydrogen and carbon.Oxides of nitrogen (NOx): Chemical compounds of nitrogen, they combine with hydrocarbons to produce smog.In order to reduce emissions, modern engines carefully control the amount of fuel they burn. They try to keep the air-to-fuel ratio very close to what is called the stoichiometric point, which is the calculated ideal ratio of air to fuel.Theoretically, at this ratio, all of the fuel will be burned using all of the oxygen in the air. For petrol engines the stoichiometric ratio is about 14.7:1. This means that for every litre of petrol, 14.7 litres of air will be burned. As engine and driving conditions change, this ratio changes as well. Sometimes it will run richer or leaner than the ideal 14.7:1.You can work it out if you have loads of spare time but the short answer is that if alll of the fuel is burned using all of the available oxygen in the air/fule mix then your bike's catalytic converter does a very good job of removing most of the regulated emissions, BMW claim up to 95% reduction in total emmisons with the use of a converter against an engine without one.Have a great weekend, I'm going riding 😀
Yeah I knew all that (Yeah right!!!)Lots of good info Gary, whats your new exhaust like ? was thinking about getting a Remus Revolution but didn't know whether it would be worth it.
Yeah I knew all that (Yeah right!!!)Lots of good info Gary, whats your new exhaust like ? was thinking about getting a Remus Revolution but didn't know whether it would be worth it.
The Akrapovic, which BMW now recommends/supplies as an option, is gorgeous YJ. It's light (the packaging it comes in wieghs more than the can), is good looking and produces a nice grumble at low revs without being too obtrusive, in the higher reve range it positively sings. Aslan has a Remus on his 1150GS and likes it.
Anonymous
Guest04/03/2007 at 8:47 amPost count: 2134The bike comes with a toolkit 😡 You can put anything in that compartement if you want to. 😀
No BMW comes with what you would call a tool kit now only about two tools now
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