[WiZ]

Man,the way you wrote the changes after each jet job seems as if ton loadsa power is coming in just through these minor tweaks ! Or is it with these Jets R Us jets ? Where do you get 'em from ? Coz even after my Stage 1 (the usual K&N - jetting stuff) i was not at all happy.

[Sankar]

I noticed a strange thing this morning. I started my bike and my foot was under the exhaust collector part (the place where al the vent tubes exit) as the bike was on center stand. I felt a pulses of air on my foot and i thought it must be from one of the vent pipes (which isn't possible inthe normal case). As i thought it wasn't and the pulses of air were actually exhaust gases.

On further investigation i found that there's a small clean round hole of about 5mm dia on the lower part of the exhaust where the cat con sits. This hole isn't threaded so i doubt a screw has unscrewed itself and opened the hole. If it's a water drain hole then why is the exhaust gases coming out through it? So what should i do, should i close it or leave it open?

I shot a photo to make it clear to you guys. Notice the carbon deposits on the hole.

[PatienceWins]

Nice pictures. Thanks for sharing.

That is a well maintained bike!!

[akshay4587]

Originally Posted by Sankar

I noticed a strange thing this morning. I started my bike and my foot was under the exhaust collector part (the place where al the vent tubes exit) as the bike was on center stand. I felt a pulses of air on my foot and i thought it must be from one of the vent pipes (which isn't possible inthe normal case). As i thought it wasn't and the pulses of air were actually exhaust gases.

On further investigation i found that there's a small clean round hole of about 5mm dia on the lower part of the exhaust where the cat con sits. This hole isn't threaded so i doubt a screw has unscrewed itself and opened the hole. If it's a water drain hole then why is the exhaust gases coming out through it? So what should i do, should i close it or leave it open?

I shot a photo to make it clear to you guys. Notice the carbon deposits on the hole.
Attachment 57687

The hole is present on all Zma's
No need to close it.
AFAIK this is a drain hole in case some water enters the exhaust.
exhaust gases will escape from it,if water enters exhaust it will escape through this hole only,exhaust pressure might help in ejection of water

[Sankar]

Originally Posted by WiZ

Man,the way you wrote the changes after each jet job seems as if ton loadsa power is coming in just through these minor tweaks ! Or is it with these Jets R Us jets ? Where do you get 'em from ? Coz even after my Stage 1 (the usual K&N - jetting stuff) i was not at all happy.

Drilled jets are usually not the best solution, drilling should be taken upon as the last resort in jetting. Like the size of the hole the shape of the entry and the exit funnels also matter a lot in fine jetting. Jestrus jets are Keihin replica jets and are of nice quality. After the mods yes power has increased a bit but not loads of it. I wanna see how it runs after the air filter change.

Did you use the K&N R1060 filter, was it inside the airbox or on the carb mouth?

Originally Posted by PatienceWins

Nice pictures. Thanks for sharing.

That is a well maintained bike!!

Nicely maintained...? It's a new bike yaar I hope it stays this way after couple of years down the time line. Thanks mate!

Originally Posted by akshay4587

The hole is present on all Zma's
No need to close it.
AFAIK this is a drain hole in case some water enters the exhaust.
exhaust gases will escape from it,if water enters exhaust it will escape through this hole only,exhaust pressure might help in ejection of water

Cool! I thought some baffle must've gotten loose or corroded and letting the exhaust leak out through the drain hole.

[PatienceWins]

Originally Posted by Sankar

Nicely maintained...? It's a new bike yaar I hope it stays this way after couple of years down the time line. Thanks mate!

Even if it is a new bike, it is as neat as a showroom one. I regularly see new bikes in bangalore which would not have seen water after leaving the showroom. How frequently do you wash it?

[JayD]

Yepp! That's a drain hole. Some pulsars also have that. Since the silencer is tilted to the top, there's a possibility of water entering into it during the rains.

[fieroid]

All 4-strokes have a water drain hole. Its an point where the rake of the canister and the primary bend pipe normally meet, so that the water can drain off.

[Sankar]

Originally Posted by PatienceWins

Even if it is a new bike, it is as neat as a showroom one. I regularly see new bikes in bangalore which would not have seen water after leaving the showroom. How frequently do you wash it?

I wash it once every week using Formula1 car wash. And polish it using Formula1 wax once a month. I should try turtlewax next.

Originally Posted by JayD

Yepp! That's a drain hole. Some pulsars also have that. Since the silencer is tilted to the top, there's a possibility of water entering into it during the rains.

Originally Posted by fieroid

All 4-strokes have a water drain hole. Its an point where the rake of the canister and the primary bend pipe normally meet, so that the water can drain off.

Cool so that's settled!

[WiZ]

@Sankar - I use the R1100.I first had it on the carb mouth,but now i use the air vessel too.

[Sankar]

Originally Posted by WiZ

@Sankar - I use the R1100.I first had it on the carb mouth,but now i use the air vessel too.

Ok. I had a bad experience when i tried R1100 on the carb mouth. But at that time i didnt have any jets to upjet.

What's an air vessel? Have you clamped the R1100 inside the airbox on to the pipe that comes from the carb like this:
http://www.team-bhp.com/forum/modifi...tml#post241605

[fieroid]

The R1100 will draw a lot more air than needed into a stock engine. Its best to mount an R1060 or an RC1060 on the carb. Provides sufficient air to the engine.
And mounting a filter inside an airbox makes no sense at all.

[Sankar]

Originally Posted by fieroid

The R1100 will draw a lot more air than needed into a stock engine. Its best to mount an R1060 or an RC1060 on the carb. Provides sufficient air to the engine.
And mounting a filter inside an airbox makes no sense at all.

What if the mounting is with the airbox lid open?

The advantage i see in mounting the air filter inside the box is that the long pipe that will act as a nice velocity stack and smoothen the airflow over the venturi. The nice long rubber pipe reduce a lot of turbulence and the rubber pipe isn't restricitive in it's diameter. The filter i ordered is a lot bigger than the R1100 but then it's a foam filter. If only high rpm performance is what we are looking for then of course a pod on the carb mouth is much better.

[WiZ]

Yeah,the 1100 had given me bad experiences too and like Joel bro said the R1060 is more than enough.

Nopes, i had removed the airbox,but kept that rubber pipe with the small box.Without that it used to flutter at the top of the revrange (ie when fitted directly onto the carbmouth)

[Sankar]

R1060 is a small filter. Small filters clog up really quick and affect performance when compared to bigger ones which doesn't get clogged up as fast due to more surface area and will continue to provide service without affecting performance for a longer time without the need of frequent clean up.

Well, there's no such thing as a too big a filter for an engine. Engine only draws in air as much as it requires even if the filter is big. A bigger filter will enable the engine to draw in more air restriction free and that creates jetting issues, the solution is to up jet. A bigger filter and/or intake plumbing after the filter will help reduce the turbulence. If the pipe ain't restrictive it's good to use along with the filter. That's what i have learnt.