Brozz exhaust

[Hancadam]

Hi everyone.

I put the eBay/Amazon exhaust that everyone buys on my Brozz. Really happy with how it turned out. Fits perfect, but did take some tinkering. I have around 3/8 to 1/2 inch clearance from the air box. Cleared everything else easily. Had to make a bracket for the rear mount.

Definitely helps out with adding a little power.
Sounds great.

[Hancadam]

Also, I had to trim more of the rear fender/mud guard out of the way. The clutch lever arm was just a little too close, so I peened the pipe in slightly. Didn't want it rattling.

Price on eBay was $89.

[2LZ]

Sounds about right on the project! Glad you like it!

[Megadan]

Turned out nice. You had some of the typical fitment issues we all tend to have. I got lucky that my head pipe cleared everything on the engine just fine, but if I was planning on keeping my stock air box I would have been SOL. Thankfully I was able to utilize the rear grab handle bolt with a spacer for my muffler mount this time around, but I did have to flatten out a small section near the rear of the frame just to buy it a small air gap. It wasn't touching, but it was close enough I would need a feeler gauge.

[Hancadam]

Thanks 2LZ and Megadan!

I ended up mounting the bracket I made to the rear grab bar bolt as well. It actually mounted up without the bracket, but was then close to the air box. The bracket luckily allowed it to drop into a better position.

I love how it's changing colors with heat cycles. Looks very cool to me.

Also, I removed the smog pump and capped off the air box/intake lines.

[tarote9025]

Originally Posted by Hancadam

Also, I removed the smog pump and capped off the air box/intake lines.

Whats the benefit of doing that? Is it basically an egr delete and allows the notor to run more efficiently?

[2LZ]

Originally Posted by tarote9025

Whats the benefit of doing that? Is it basically an egr delete and allows the notor to run more efficiently?

It's not an egr. It's a fresh air injection into the exhaust port to toss fresh oxygen on the hot cat to help it do its job. Once the cat is removed (new exhaust), that air injection will be tossing fresh oxygen on your new muffler packing.
Best to disable it if you remove the cat.

[NzBrakelathes]

Originally Posted by 2LZ

It's not an egr. It's a fresh air injection into the exhaust port to toss fresh oxygen on the hot cat to help it do its job. Once the cat is removed (new exhaust), that air injection will be tossing fresh oxygen on your new muffler packing.
Best to disable it if you remove the cat.

Incorrect Sir.

The vacuum from intake opens the valve under the tank and allows the exhaust gasses to be recycled into the air box.
THAT IS only if the valve is REAL - yes I have seen them FAKE not able to ever function.

Take it all off and if popular I could supply the blanking plugs or do as some ppl do just cover the hole etc or cut a gasket without a hole n leave it all as if it is connected.

[tarote9025]

Originally Posted by NzBrakelathes

Incorrect Sir.

The vacuum from intake opens the valve under the tank and allows the exhaust gasses to be recycled into the air box.
THAT IS only if the valve is REAL - yes I have seen them FAKE not able to ever function.

Take it all off and if popular I could supply the blanking plugs or do as some ppl do just cover the hole etc or cut a gasket without a hole n leave it all as if it is connected.

Whats the benefit of removing it?

[Megadan]

Originally Posted by NzBrakelathes

Incorrect Sir.

The vacuum from intake opens the valve under the tank and allows the exhaust gasses to be recycled into the air box.
THAT IS only if the valve is REAL - yes I have seen them FAKE not able to ever function.

Take it all off and if popular I could supply the blanking plugs or do as some ppl do just cover the hole etc or cut a gasket without a hole n leave it all as if it is connected.

Actually, you are incorrect sir. It is an air pump. Known as a pulse air injection pump (aka PAIR ). It uses a line from the intake between the carb and cylinder head to create the pulses needed to drive the pump. This draws fresh air from the air box via another line to the air box, to the pump and then pumps fresh air into the hot exhaust path to help burn off any unburned hydrocarbons and aid in the catalyst function.

If you need any other proof, the simple fact that all of the lines in the system are rubber should be a clue, especially the unit off of the head. If it was true EGR, they would have to be metal for the simple fact that they would melt/fail rather quickly with up to 1000 degree exhaust gasses passing through them.

Other proof that it is not EGR is the simple fact that it is a pump. True EGR doesn't need a pump to function, just a valve. The extremely hot exhaust gasses are also very high pressure, and don't need assistance in traveling through a pipe.

This is the same basic system found on almost every emissions compliant bike sold in the U.S. No bike comes with EGR, but they all have a PAIR system and a EVAP charcoal canister (aka, TT250) as part of 50 state compliance.

Further evidence of this is a TT250 with an exhaust installed on it makes lots of nice after fires (proper name for what people call backfires, which actually go through the intake). This is the same reason why other big name bikes with exhausts block off or delete the pair system when an aftermarket system is installed. The extra oxygen in the system causes unburned fuel to essentially ignite on its own within the exhaust.

[pete]

ok.. what it is or what it is not....

but the short is if you remove the AIS and not the cat
the cat will clog up faster....


...

[Megadan]

Apologies, Hancadam, for the above post in your thread. If you so desire you can have it deleted by an admin and I wouldn't mind. It just had to be said.

[Hancadam]

No apology needed, none of the discussion bothers me.

[2LZ]

Back to our regularly scheduled program...

Hancadam, since I have this freakish need to make brackets out of scrap, I ended up mounting it like this on Mrs. 2LZ TT250. I thought it turned out cool and I also fulfilled my bracket fetish. ;-)
My main concern was to have the muffler spaced out enough as to not cook the license plate plastic holder...which has been done here prior.

[tarote9025]

Originally Posted by 2LZ

Back to our regularly scheduled program...

Hancadam, since I have this freakish need to make brackets out of scrap, I ended up mounting it like this on Mrs. 2LZ TT250. I thought it turned out cool and I also fulfilled my bracket fetish. ;-)
My main concern was to have the muffler spaced out enough as to not cook the license plate plastic holder...which has been done here prior.

That is definanetly a more sophisticated solution then pounding it in to submission with a rubber mallet like i did lol. And for the record my rear fender melted in the best place for it to, the license plate covers it up. And for dual sports question it helps the exhaust gases travel through the muffler better i wrapped mine for the specific reason i dont want my pants to catch on fire or burn my calf while going down the road. Everytime it rains it will smoke for about 5 minutes until that moisture burns off. Every time i come from a wet ride off road or get caught in the rain i have people honking thinking my motor is about to blow up but they give me more room on the road so win win in my opinion