exhaust sputter?

BeachBuzz · Post by **BeachBuzz** » Mon Jun 23, 2008 1:25 pm

OK Blur owners, I've got about 500 bdu's on the odo and I'm concerned about my exhaust. it seems to have some sort of leak in the system, not that I can hear while under power but when I take off from a stop I can feel puffs of air on my left ankle. also when I let off the throttle and coast it makes a sort of puffing sound that doesnt seem like it's coming from the end of the pipe. I'm wondering if there is some sort of forced air intake that might be causing the sensation on my ankle or do I have a gasket leak?

illnoise · Post by **illnoise** » Mon Jun 23, 2008 2:55 pm

Hm, that doesn't sound right, get it checked out.

Bb.

r4vi · Post by **r4vi** » Thu Jun 26, 2008 3:45 pm

This may or may not be helpful - my G-Max (your Blur) was puffing a little, would backfire through the carb on deceleration...Spark plug was white.

Turned out the O-ring that seals the intake manifold to the head was missing ex-factory. That 20 cent O-ring cost the importer a fortune in warranty claims - first a replacement cylinder, piston and head at 1900 GDUs (G-Max Distance Units - yes my speedo is out by around 20% even after replacement under warranty), then the bottom end 900km later ('cos the moron mechanic refused to open the case up to clean out particles deposited by the introduction of a 20mm hole in the top of the piston)

I am a tad confused why you would feel the puffing on your left ankle, if your foot is on the footboard. There's really nowhere it could be coming from...

If you feel the puffing when your left foot is on the GROUND that's a different manner, and I know exactly what that is. Get under your scoot and look at the front of the variator cover. It has a right-angled black rubber boot. This boot should line up with an opening on the plastic cowling around the cylinder. Air gets sucked in by the fan on the right hand side, blows over the motor, and is directed at the boot to (hopefully) inject air into the CVT. I got worried first few times I took off on my scoot due to this until I checked what it was...

Sadly mine doesn't do this any more as the IDIOT importers put the wrong plastic cowling on my scoot when they fixed the bottom end - now my cowling opening faces down so I get no airflow into my CVT.

Check your spark plug to see if it's going white, and put your scoot on the centre stand and run it to see if the puff is coming from that cowling opening. If it's coming from the cowling, that's all good. If you have a WHITE spark plug (or going white) you might be missing an O-ring like I was.

BeachBuzz · Post by **BeachBuzz** » Thu Jun 26, 2008 5:39 pm

r4vi wrote:

If you feel the puffing when your left foot is on the GROUND that's a different manner, and I know exactly what that is. Get under your scoot and look at the front of the variator cover. It has a right-angled black rubber boot. This boot should line up with an opening on the plastic cowling around the cylinder. Air gets sucked in by the fan on the right hand side, blows over the motor, and is directed at the boot to (hopefully) inject air into the CVT. I got worried first few times I took off on my scoot due to this until I checked what it was...

Sadly mine doesn't do this any more as the IDIOT importers put the wrong plastic cowling on my scoot when they fixed the bottom end - now my cowling opening faces down so I get no airflow into my CVT.

I was/am feeling the air while my foot is on the ground, actually it increases as I roll on the throttle and pick up my foot. I did put it up on the centerstand and made a little closer inspection. It is definitely not coming from the exhaust/manifold/gasket

I think all I'm feeling is the induction fan blowing over the motor. It just made me worry because I had a similar problem with my Burgman where the manifold gasket was missing or had disintegrated. The problem eventually got loud enough to indicate a problem and the gasket was replaced under warranty. I don't have a lot of miles on this scoot yet and had never experienced any kind of forced air cooling on my other scoots so it piqued my interest. I think all is good but I will mention it to the shop when I take it in for the first official service - if I can figure out when that is supposed to happen?? 500 BDU's, KMs Miles????? I guess sooner is better than later so I'll probably schedule it in the next couple of weeks, while I still have the TGB at home to commute on before it retires to the beach.

thanks for your input

Erlkonig · Post by **Erlkonig** » Thu Jun 26, 2008 11:32 pm

airflow from under center stand is normal my 200 is very hot like heater.

I replaced a oem export exhaust pipe and found backfiring on deceleration in low speed sounds like baby fart high speed very loud

I just increase idle rpm a little bit the noise is decrease to unnoticed

export exhaust, throttle all way down up to 120km and top speed have not try yet

demostic exhaust, throttle all way down around 105 km and need to wait couple second to 130 km

babblefish · Post by **babblefish** » Tue Jul 01, 2008 7:03 am

I know what that "puff" you're feeling is - it's the engine's cooling air exhaust. It exits from under the engine's cooling shroud, pointing down and a bit to the left. Look underneath your bike on the left side and you'll see an opening in the shroud and the engine's cylinder just beyond that. Theres a fan on the right side (that air scoop looking thing with the opening that faces down) that sucks air in and blows it across the cylinder and head then exits on the left. Nothing to worry about.