[clintp86]

Hello there. I'm new to the forums and I have a question concerning my new Muzzy exhaust on my new 750 Brute Force. Here's the deal. I wrapped the pipes wherever I could except for the front header pipe coming off the exhaust port because I didn't see the need. So the night I got the exhaust all bolted on, I decided to test ride it. I was cruising along at 20 mph just taking it easy. Since it was dark and out of curiosity, I took a peek at the front header pipe and it was glowing orange!! Not 2 or 3 inches but the whole thing! This really surprised me because I wasn't running it hard at all. I came to an immediate stop, got off and looked at the rear header pipe and it was glowing the same way.

This was little over 2 months ago now and I've talked to several people about it at work. Some say it could be running a bit lean and some say it could just be normal so I went with normal as I have ridden it with no problems at all. I'm still a bit concerned because I think the fuel injection would have adjusted to the difference in back pressure by now but the pipes still glow at night and I hope I haven't done any damage to say, the valves. I don't want to spend money on a programmer because the quad runs very strong. What do you guys think the problem is? Any suggestions? Thanks!

 

[skip nay]

You need to get a fuel controller like I did. EHS Racing Store-

You are running it lean and it won't last forever running it like that. Plus it will probably pick up a few horses.

 

[clintp86]

Do those automatically adjust the air/fuel mixture as you run the quad or do you have to manually set them?

 

[skip nay]

Do those automatically adjust the air/fuel mixture as you run the quad or do you have to manually set them?

You have to do it manually. Set it and forget it. It will only add not take it away. You can get a controller like a VDI that does it all.

 

[Hunterworks]

Let me save you some money.

It is normal for any stainless pipe to glow red, it is stainless for you.

On our dyno I have them glowing all the way to the mufflers.

This does not mean however you still might be running lean. We see on the 750 Teryx with muzzy pipe it runs slightly lean but nothing dangerous.

Just get a Muzzy Digitune for the Brute and it will already be set up for you.

Todd

 

[greasemonkey]

Pushing the engine on a dyno you can get the pipes to glow but if they are glowing after an easy ride then it is way too lean.That is alot of heat going by the exhaust valves all of the time as opposed to every once in a while.I would not drive it too much like that .You can burn an exhaust valve and seat.On Harleys, which have an aluninum head like the Kawi I have seen melted valve guides and other damage.

 

[clintp86]

I have noticed that when the quad is started cold, it kinda sputters when I rev it up a little. Same thing happens when I'm doing maybe 5 mph at normal operating temp. I can hear it kinda spit until I get the rpms up a little more. I'm guessing that's due to the lean mixture. I didn't think there was something ever right about it. I just hope I haven't burned any valves.

I really like the sound of the v twin when its cold. It sounds like a big block V8 with open headers. But as the exhaust warms up, it sounds more like a single cylinder quad at higher speeds. Does everybody experience this? I was told by somebody that the sound of the exhaust changes as it gets hotter. I believe it but in my case, it just gets louder and louder as the pipes get hotter so I'm hoping that the controllers will do the trick and keep the exhaust tone deep and mellow by the pipes not turning orange.

 

[Hunterworks]

Mine stays red going down road too and the air/fuel is spot on.