[Jim G]

dbrain, I have no idea how loud the exhaust would sound at 100 mph, but I can tell you that at 60 mph, wearing my Klim helmet (which is NOT a quiet helmet) its not very audible over the wind noise. I could tour with this level of exhaust noise.

Jim G

 

[dbrain]

dbrain, I have no idea how loud the exhaust would sound at 100 mph, but I can tell you that at 60 mph, wearing my Klim helmet (which is NOT a quiet helmet) its not very audible over the wind noise. I could tour with this level of exhaust noise.

Jim G

It should be right. There was a V4R there on the weekend with a full system that was stamped for 107dba. These things are 98-100db

Possibly a dumb question, because I've never done this before, but am too cheap to pay someone. For the install you mention silicone sealant on the muffler to muffler pipe. and muffler pipe to mid pipe, but water as lubricant for everything else. Why do the other connections not need/use sealant?

 

[Jim G]

It should be right. There was a V4R there on the weekend with a full system that was stamped for 107dba. These things are 98-100db

Possibly a dumb question, because I've never done this before, but am too cheap to pay someone. For the install you mention silicone sealant on the muffler to muffler pipe. and muffler pipe to mid pipe, but water as lubricant for everything else. Why do the other connections not need/use sealant?

The other connections are more than tight enough without the sealant. Zero leakage. In fact, the water is needed as a lubricant (ok with stainless steel) to make sliding those connections together and doing so ACCURATELY - i.e. as far together as needed, but not TOO far. It would be hard to pull any of them back OUTWARD because of the tight fit!

But the rearmost 2 connections, the muffler to muffler pipe. and muffler pipe to mid pipe, are notably looser, probably to ease installation, and so more prone to leak with exhaust air being pushed through. In fact, on my install, even with the sealant in there, the muffler pipe to mid pipe connection, upon first startup, leaked a tiny bit of air, but quickly stopped as the silicone sealant (good to 400 degrees or more) was heated and sealed the connection. No leakage after that.

Also, using sealant on the other connections, when not necessary, would make future disassembly, if ever needed, much harder, as the silicone really does "seal" parts together.

I had done numerous exhaust systems in the past, and kept the assembly and disassembly lessons I had learned on them foremost in my mind!

I do have one new suggestion though. I think I recall the removable baffle in this Delkevic system as having no hole in its end that faces the FRONT of the bike. This makes it impossible for a tuner to push an AFR sampling tube up the exhaust sufficiently to get a TRUE afr reading when tuning the bike on a dyno (which you might be contemplating doing). If you do go to a dyno tuner eventually, you'll want to have the baffle either entirely out of the system (if that is the way you will be running the system after the tune), or you'll want to drill a small hole in the "front" end of the baffle, of large enough diameter to allow the AFR sampling tube to pass through it. Of course, the larger you make that hole, the louder the exhaust will become.

Or, you could make the hole in the baffle JUST large enough to pass the sampling tube through it, tune the bike for a "baffled" exhaust, and then after the tuning session simply replace the drilled baffle with a spare UNdrilled one.

Finally, SOME other owners of SOME exhausts (any brand) that have removable baffles have reported that if you remove the baffle, but either reinstall or leave out the screw that fastens the baffle into the exhaust in place, you either get, or eliminate, an audible "whistle". This is caused by the exhaust airflow going past either the screw, or the hole in the side of the exhaust that accepts the screw, acting as a musical instrument like a horn. No kidding.

Jim G

 

[dbrain]

Great, thanks a ton for the detailed information @Jim G. I'll probably hold off on tuning unless there's some obvious tune issues, mostly because of cost, but great to know about the changes needed for sampling if/when I go that route.

Exhaust should be here early next week, AIS disabling stuff end of next week. So I guess next weekend is going to be the surgery.

 

[Jim G]

Great, thanks a ton for the detailed information @Jim G. I'll probably hold off on tuning unless there's some obvious tune issues, mostly because of cost, but great to know about the changes needed for sampling if/when I go that route.

Exhaust should be here early next week, AIS disabling stuff end of next week. So I guess next weekend is going to be the surgery.

dbrain: During BOTH initial installation, and final torquing, of the header nuts, be sure to do the tightening all four header pipe nuts EVENLY, alternating back and forth across all 4, to ensure that the header pipes are EVENLY and FULLY seated against their exhaust gaskets. If you "****" the header pipes at all, you will not get a full seal against the exhaust gaskets in the head, nor a proper positioning of the header pipes. Be patient and do this slowly, a bit of a turn at a time on each nut.

After installation, run the bike at least 25 miles under varying heat loads. Wait till the engine has cooled completely. Then, check the torque on the header bolts at the cylinder head. When I checked mine after my 2nd ride, the torque wrench indicated that those bolts had lost just a bit of the torque I had applied (a small rotation of the torque wrench was required to get 1 click of the torque wrench). This is likely a result of the heat cycling effect on the exhaust gaskets or even a minute amount of "settling in" movement of the ends of the header pipes.

I am assuming you have a torque wrench. If not, be cautious about the torque you apply initially and then when checking again, as stripping those header studs would require an immediate replacement, which requires the right tools, experienced technique, and new studs.

Jim G

 

[dbrain]

dbrain: After installation, run the bike at least 25 miles under varying heat loads. Wait till the engine has cooled completely. Then, check the torque on the header bolts at the cylinder head. When I checked mine after my 2nd ride, the torque wrench indicated that those bolts had lost just a bit of the torque I had applied (a small rotation of the torque wrench was required to get 1 click of the torque wrench). This is likely a result of the heat cycling effect on the exhaust gaskets or even a minute amount of "settling in" movement of the ends of the header pipes.

I am assuming you have a torque wrench. If not, be cautious about the torque you apply initially and then when checking again, as stripping those header studs would require an immediate replacement, which requires the right tools and new studs.

Jim G

I was considering doing what the STG guy does and whacking some sealant on the header bolt threads, as I intend to do some club racing on bike once I have a few more bits and pieces, but good call, I'll do the 40km thing first to let things settle.

Aha yeah, I wouldn't touch my bike without a torque wrench. I like to do things to spec. My other bike has a ton of aluminium on it as well, so it's really easy to strip things.

 

[dbrain]

@Jim G out of interest did you look into the oversized/quieter Delkevic baffles at all? Just found out they existed, so ordered one to hopefully cure fears of being booted off track for noise.

 

[Jim G]

@Jim G out of interest did you look into the oversized/quieter Delkevic baffles at all? Just found out they existed, so ordered one to hopefully cure fears of being booted off track for noise.

No, I did not know those existed. Did you find those on the British or U.S. website? I don't think that I would need or want quieter baffles, but then at my age my hearing is perhaps no longer that good!

Jim G

 

[dbrain]

No, I did not know those existed. Did you find those on the British or U.S. website? I don't think that I would need or want quieter baffles, but then at my age my hearing is perhaps no longer that good!

Jim G

They are on the UK site, as well as the other distributors. I ordered from the Australian site. They seem to have different names depending on region.

I can't seem to find any info on the noise difference, just that it sounds about the same at idle but calms it down a bit at high revs.

I'll see how the bike sounds with the stock baffle, if I'm concerned about noise levels I'll put that thing in, and either way take it to the track. Better than carrying the OEM silencer around.

Be interested to see if it changes the feel of the bike at all either way. Personally I'm only switching exhausts because the stock interferes with my foot too much, performance and sound are just optional extras (as long as it's not lowering performance I don't mind).

 

[Jim G]

They are on the UK site, as well as the other distributors. I ordered from the Australian site. They seem to have different names depending on region.

I can't seem to find any info on the noise difference, just that it sounds about the same at idle but calms it down a bit at high revs.

I'll see how the bike sounds with the stock baffle, if I'm concerned about noise levels I'll put that thing in, and either way take it to the track. Better than carrying the OEM silencer around.

Be interested to see if it changes the feel of the bike at all either way. Personally I'm only switching exhausts because the stock interferes with my foot too much, performance and sound are just optional extras (as long as it's not lowering performance I don't mind).

Yes, the OEM muffler on the 400 was a rare mistake made by the design team. First, its position, as you point out, interferes with just about any rider's foot. Second, that flat black paint finish is super ugly. Third, the heat shield over the muffler looks cheap and makes the foot interference problem even worse. Fourth, that muffler, given that it does NOT contain the Cat, is remarkably heavy for just a muffler, and given the design team's emphasis on weight reduction everywhere else (I had to work hard to get 19 lb off the bike while keeping it streetable).

It's totally puzzling how that OEM muffler got past the design quality and prototype testing stages.

Jim G

 

[Kiwi Rider]

@Jim G out of interest did you look into the oversized/quieter Delkevic baffles at all? Just found out they existed, so ordered one to hopefully cure fears of being booted off track for noise.

I wouldnt sweat it mate, i had a Delkevic on another bike (CBR300) and with the regular dB reducer in that came with the pipe it was absolutely fine for a track environment.
Also, are they actually testing the bikes at this track your going to? I find a lot of the tracks I go to have signs about max dB levels etc but it's just there to keep the council or who ever happy and there's not any actual testing being done.

 

[Jim G]

The track here on Vancouver Island, which runs both expensive rich mens' cars and motorcycles, is being pretty aggressively harassed and attacked by its neighbours for noise. Recently in fact, The Town denied the track a permit to expand, despite the expansion being in conformance with an earlier agreement with The Town. The case is currently in litigation.

Tracks are like airports. They get built "out in the country" but then developers build homes around them, and the harassment begins.

Outside the track, on the streets in wide areas of The Island, there is a lot of public resentment against Harley owners who run loud exhausts. Those exhausts ARE loud, but quieter than many diesel trucks and even some diesel pickups, but people view noise "for pleasure" differently than "noise for business reasons hauling heavy loads".

I try to keep a low noise profile when in town, which is easy since I can get "out of town" in 6 kilometers or so, and out of populated areas beyond that in an extra 5 or so kilometers.

But, I wouldn't call ANY of the exhausts I've "loud" other than the D&D performance exhaust I had on the Harley breakout i owned. THAT exhaust was LOUD, and I did not enjoy the volume. It was TOO loud to make for pleasant cruising when that is all I wanted to do with friends, and nobody wanted to be behind me on group rides! That Harley had a Stage 4 kit with very high cranking psi, and the D&D exhaust made it sound like rapidfire gunshots.

When I sold it to a local dealer, and he started it up for a prospective buyer in his showroom, it was deafening!

But hey, Harleys bring out the bad boy (or bad girl) in everyone.

Jim G

 

[dbrain]

I wouldnt sweat it mate, i had a Delkevic on another bike (CBR300) and with the regular dB reducer in that came with the pipe it was absolutely fine for a track environment.
Also, are they actually testing the bikes at this track your going to? I find a lot of the tracks I go to have signs about max dB levels etc but it's just there to keep the council or who ever happy and there's not any actual testing being done.

Ah this particular track has been getting pretty bad recently. They have actual council testers there often. 95db for a ride by is the max, and they will re-test you after getting picked up for a stationary 98db, which is equivalent apparently. Not entirely sure how they do the stationary test (what rpm etc.).

They have been looking to expand a bit, and as part of that have upped their noise testing and started enforcing it properly.

The Delkevic site talks about 98-100db stationary at 60% rpm (whatever 60% means). So it's borderline, depending on the testing method the track uses.

 

[Jim G]

. . .
The Delkevic site talks about 98-100db stationary at 60% rpm (whatever 60% means).
. . .

i THINK they mean at 60% of the rev limit, but am not sure. The purpose of such a rule would be to have a specific rpm that would make sense whether the bike being tested in a Harley where 60% would be 60% of maybe 6000 rpm = 3600 rpm, whereas your Ninja would be tested at 60% of 12,000 rpm = 7200 rpm. Testing your 400 at 3600 rpm would give you an easy pass, whereas the Harley would really bellow at 3600 rpm.

In The U.S, in jurisdictions where noise levels are codified and enforced, there is also a "standard" for what rpm to do the test at, and where (what distance at what angle and what height) to place the microphone.

Jim G

 

[dbrain]

i THINK they mean at 60% of the rev limit, but am not sure. The purpose of such a rule would be to have a specific rpm that would make sense whether the bike being tested in a Harley where 60% would be 60% of maybe 6000 rpm = 3600 rpm, whereas your Ninja would be tested at 60% of 12,000 rpm = 7200 rpm. Testing your 400 at 3600 rpm would give you an easy pass, whereas the Harley would really bellow at 3600 rpm.

In The U.S, in jurisdictions where noise levels are codified and enforced, there is also a "standard" for what rpm to do the test at, and where (what distance at what angle and what height) to place the microphone.

Jim G

Yeah, I don't know if it's 60% of the total rev limit, or the non red line? Based on this video they suggest their testing is "standard motorsport testing procedure", the track also talks about the stationary test being "sport testing". Which makes me think the 60% deal Delkevic uses is potentially the same as what the track would use, meaning I'd want to be on 98 or under. That being said, I can't find anything that actually describes the "sport testing" procedure.

I've found the Australian road testing rules, and it's something like 3750rpm for a Ninja 400, which is nowhere near 60%.

I'll probably ride without the oversized baffle initially to get a feel for it, and it's noise, then try the oversized baffle and see if there's any noticeable change in bike feel. If not I'll just leave it in. Honestly, I'd be fine with the stock exhaust if it wasn't made for baby feet / riding with your heels on the pegs.

 

[dbrain]

@Jim G I noticed you mentioned the headers needed to be knocked into the collector, mine seem to slide and out pretty freely.
Awkward video trying to show here. I can push as far as I want, to the point where it would dent the header pipe.

Is this concerning? Should this supposed to be a tight seal? Based on your previous posts it would seem so.

 

[Jim G]

@Jim G I noticed you mentioned the headers needed to be knocked into the collector, mine seem to slide and out pretty freely.
Awkward video trying to show here. I can push as far as I want, to the point where it would dent the header pipe.

Is this concerning? Should this supposed to be a tight seal? Based on your previous posts it would seem so.

If yours is that loose, I'd use the silicone sealant. I'm not sure how long the sealant takes to "dry" (harden), so I would try to do the final system adjustments and tightening fairly expeditiously (i.e. in one session, not "I'll finish it tomorrow"). I try to limit the amount of silicone I use on an exhaust as it makes both disassembly and subsequent re-use of the exhaust harder and more tedious.

Jim G

 

[dbrain]

If yours is that loose, I'd use the silicone sealant. I'm not sure how long the sealant takes to "dry" (harden), so I would try to do the final system adjustments and tightening fairly expeditiously (i.e. in one session, not "I'll finish it tomorrow"). I try to limit the amount of silicone I use on an exhaust as it makes both disassembly and subsequent re-use of the exhaust harder and more tedious.

Jim G

Thanks, yeah I'm mocking it all up first and will step through it all when I know I'll have a good couple of hours to do it all completely. Sure it won't take that long but better safe than sorry.

It does get a bit tighter when the headers are mounted loosely and I connect to the collector, but still doable by hand rather than getting a mallot involved.

Just working out the actual slip on part now and I think, after picking up kid and putting it in its cage (read: bed/wife gets home) I'll do the real install.

 

[dbrain]

Got it "done". Looks decent, sound wise it's ok but I think I'll like having the oversized baffle.
Managed to cut the **** out of my hands on the exhaust clamp.

"Done" because it has leaks, so I'm going to take the collector and backwards apart again, hopefully leaving headers on (worst case loosening) and gasket the **** out of the thing. I only put a little bit on previously, so it either needed more, or in my fiddling getting it back together I've likely smudged and thinned it out too much.

Here's a pic on a Ninja 400 in a dirty garage.

 

[Tracy]

Got it "done". Looks decent, sound wise it's ok but I think I'll like having the oversized baffle.
Managed to cut the **** out of my hands on the exhaust clamp.

"Done" because it has leaks, so I'm going to take the collector and backwards apart again, hopefully leaving headers on (worst case loosening) and gasket the **** out of the thing. I only put a little bit on previously, so it either needed more, or in my fiddling getting it back together I've likely smudged and thinned it out too much.

Here's a pic on a Ninja 400 in a dirty garage.
View attachment 16912

Thats what makes it a garage
🐉