New exhaust

[ThePowster]

So..... My Nighthawk has aftermarket performance cans on and it sounds... Well... Like a sewing machine.

I took the cans off and wow she sure came alive. It sounded like it came from the pit of hell itself. It was bloody marvellous! Popping and banging on the down shifts, had a right smile on me chops 

So then I had a problem. I want the sound of the bike with a straight through system, but I didn't just want cut exhaust pipe as it looked ugly. The solution? Simple exhaust tips. Sounds easy but finding a suitable can or system proved tough.

I found these on AliExpress and they wasn't cheap, £60 delivered.

So it's two angled exhaust tips that were for an R6 or any other bike with a 45mm exhaust.

Now, the Nighthawk has a 39mm pipe so I'm 6mm short. 

To rectify this I purchased some graphite gaskets which should bridge the gap.

So we have....

Nighthawk exhaust no can - 39mm
These exhaust tips - 45mm
Graphite gaskets 39-45mm

So I'm hoping that the graphite gaskets slip on my exhausts and the exhaust tips slip on the gaskets on the exhausts and it tightens right up 🤞

That's the plan anyway   will it work ? Hmmm 🤔 will see.

So the hex mesh on the end I'd say is responsible for maybe 20% of the outlet, or another way is it's 20% more blocked than straight through as the gases will hit the hex heads effectively being a slight baffle. I'm hoping anyway.

The only question is, do I spray them black and maybe add a small metal akrapovic decal. Will see.

I guess you'll wanna see some pics 

Oh and this is why I want the stage II Dynojet kit installed as it'll need more fuel for the more or less straight through system.

[Bob H]

...So the hex mesh on the end I'd say is responsible for maybe 20% of the outlet, or another way is it's 20% more blocked than straight through as the gases will hit the hex heads effectively being a slight baffle. I'm hoping anyway.

the mesh will keep the rodents out - I don't think they will reduce the sound level much.

[ThePowster]

Afternoon chaps.

Ok so I got in the garage today and I managed to install my exhaust tips to the Nighthawk.

The graphite gaskets worked well and was 2mm too thick so I rotated the sleeve on in a back and forth twisting motion which took a thin slice out of it and then I nipped them both up, half hr job.

The cans I took off I'd guesstimate to weigh approx 7kg each, so it's about a 30lb saving.

I managed to nip it out for a short spin as I'm on rear brake only and the bike wasn't happy at all. It's like it's running on 2 cylinders. I've always had a problem with it and I suspect the coils have had it so I'll be replacing those next.

She's loud   No doubt about that. But so are hogs and most custom bobbers. 

[mollusc]

Everyone has their own taste I guess.

[Bob H]

...I suspect the coils have had it so I'll be replacing those next.

I just checked my coils "per the book" last week and was astounded at how easy it is.
You just set the multimeter to Ohms.
Check the resistance between the spark plug leads and compare to the range it is supposed to be in. That is the "secondary" reading, but you do that first while the wires are still attached to the coils.

Then you pull the wires from the coils, and stick a probe into each receptacle on the coil where the spark plug leads plugged into. that is the "primary" reading. Mine were all within range.

I opened that door because I was replacing my spark plug leads and was curious about the coils.

If nothing else, it will be a learning experience for you rather than just throwing parts at it.

She's loud  No doubt about that. But so are hogs and most custom bobbers.

Let's suppose the guy down the street is a wanker... Oh never mind.

[ThePowster]

That's a good idea about the coils.

I've just bought a new flashy digital readout multimeter, I'll do that next week and let you know what my readings are. Im hoping there out otherwise I've no idea why she isn't pulling. This happens with or without exhaust change.

[Bob H]

...otherwise I've no idea why she isn't pulling. This happens with or without exhaust change.

Are you running the stock intake, or did you install this yet?

[ThePowster]

As soon as my media blasting cabinet arrives next week and I clean the carbs and paint um n drop the Dynojet kit in, I'll add that set up above to the carbs and onto the bike and see how she goes 🤞

[ThePowster]

My bike in the past has sounded funny. A mate of mine touched the exhaust and said one was cold. Next time I started it they was all hot. So maybe it was running on 3 cylinders.

Today she wouldn't pull at all. Did less than a mile and limped her home. I've ran her before with no exhaust and no problems, I know I've got electrical issues all over the place.

[Bob H]

A mate of mine touched the exhaust and said one was cold. Next time I started it they was all hot. So maybe it was running on 3 cylinders.

The resistance test I mentioned earlier on this thread would detect a bad spark plug wire when doing the "secondary" resistance test.
Recently I got a very inexpensive thermometer ($15, do a search for: Etekcity Infrared Thermometer Laser Temperature Gun 774)
One of my vehicles requires temperature reading to determine Transmission fluid level. So I got that thing, changed the fluid - and since then have found many uses for it.
You point the laser dot on each exhaust pipe and will instantly see if one is lower than the others due to a misfire even if it is intermittent.

[ThePowster]

Damn I bought one yesterday and it only goes to 490 oc or 924 of, so I guess that won't work. Maybe for the first few minutes while she's on choke.

I'll definitely check the coils when I can get round to it.

Luckily I have another Nighthawk in spares so I can swap out the CDI box and change things. Bikes never revved clean since I had it and first thing I did was put fresh plugs in it.

[Bob H]

Damn I bought one yesterday and it only goes to 490 oc or 924 of, so I guess that won't work. Maybe for the first few minutes while she's on choke.

Is the "o" degrees? That should work fine at full temperature, not just the first few minutes.

Your thermometer is as good or better than the one I bought - and mine will read a hot exhaust header without maxing out. Watch the following video starting at 7 minutes in (not my video). Honda NC 750 after an hour of riding the exhaust header is 250 Celsius (482 Fahrenheit)

[ThePowster]

Ah that's really good to know. Phew 👍