Kiwi Biker forums - Blogs - AllanB https://www.kiwibiker.co.nz/forums/blog.php/7248-AllanB Kiwi Biker - New Zealand motorcycle community en Sun, 03 May 2026 21:30:26 GMT vBulletin 20 https://www.kiwibiker.co.nz/forums/images/BP-Brown/misc/rss.jpg Kiwi Biker forums - Blogs - AllanB https://www.kiwibiker.co.nz/forums/blog.php/7248-AllanB 3 months later ..... https://www.kiwibiker.co.nz/forums/entry.php/1184-3-months-later Fri, 20 Nov 2009 04:12:41 GMT It’s been a while since I posted any progress (3 months) – mainly due to there being very little! I appear to have been always ‘busy’ and away from the garage lately. Some shed time last weekend moved things along more. I’ve had a set of brackets welded into the inner or the cone allowing me... It’s been a while since I posted any progress (3 months) – mainly due to there being very little! I appear to have been always ‘busy’ and away from the garage lately. Some shed time last weekend moved things along more.

I’ve had a set of brackets welded into the inner or the cone allowing me to drill and tap them so the end caps may be bolted in from the rear. I then bent and welded a bit of 5mm steel rod to the end cap forming a neat seal with the front cone, plus this will act as a base for the reverse cone to be welded to.

Next was to form a pair of reverse cones for the end caps. The hardest part of this was getting the size of the cone right. I’d used a few internet formulas but the cones never ended up the size/shape I wanted so I resorted to tried and true paper forming until I had the shape I wanted. There is a bag of cardboard rejects under the bench …… And a metal one after cutting it out, forming it and deciding it was not ‘right’.

The end cones were cut out of 1.5mm plate with my good old Black & Decker jigsaw, then carefully hand rolled over a piece of pipe. A quick zap with the welder to join them and I grabbed my trusty hammer and former to roll the edges over. These cones will be welded to the rod and everything ground down for a clean finish.

I’ve also welded a couple of threaded mounting tabs to the inlet end of the pipes so I can bolt on an alloy heat shield which hide the muffler mounting clamps. One heat shield is 90% finished (Mark II shield), the other a cardboard template ……

With the dollar up against the US I got on the net and shouted myself a set of stainless steel cores. These spunky units are 40% holes, weigh almost nothing and appear identical to the cores used by a couple of the big brand systems. It’s a shame no one will see them!

So I’m almost done. Hopefully some shed time this weekend will allow me to finish the end cones and the next pictures should be of at least one complete unit!

A quick weigh-in on the scales shows I’ve saved exactly 1 kg per muffler with the new ones – an added bonus.
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]]> AllanB https://www.kiwibiker.co.nz/forums/entry.php/1184-3-months-later Slowly getting there. 11.7.09 https://www.kiwibiker.co.nz/forums/entry.php/968-Slowly-getting-there-11-7-09 Mon, 13 Jul 2009 05:44:43 GMT *Slowly getting there.* The mounting bracket has been completed for the right side – I’ve made it so I can use the factory rubber grommets to absorb any vibration and allow a bit of movement. Brackets take a bit of pissing around with – 2 hours went into this one and there is a dud one in the... Slowly getting there.
The mounting bracket has been completed for the right side – I’ve made it so I can use the factory rubber grommets to absorb any vibration and allow a bit of movement.

Brackets take a bit of pissing around with – 2 hours went into this one and there is a dud one in the bottom of the rubbish tin!

The left muffler has the joiner and mid pipes fabricated and tack welded together – visibly held held on in the pictures with a bungee strap! The bracket for this side will probably frustrat me – it will need to be perfect so the outlet aligns with the other side.

I actually went for a spin up and down the drive with it like this on Saturday (I could not resist). Then I pulled them off and put the stock cans back on so I could go for a real ride.

Tools
A friend said the other day that he’d like to make some but hasn’t any flashy tools. I have not used any either – my basic tools consist of a hacksaw, grinder, files, hammers, duck tape, marker pen and a metal vice. I’ve an arc welder that I use to carefully tack it all together and the finish welding (mig) has been out-sourced as serious arc use on these pipes will blow holes in the metal – it’s OK on low for a quick tacking dab. A mig welder :love: is on my wish list ….. sigh.

The panel hammer has been used to roll the edges of the mid pipe to fit the smaller pipe that slips over the stock pipe. This is easy to do by placing a piece of heavy pipe of a smaller diameter in the vice and use this with the hammer to roll the edge of the 50mm pipe. Take your time and you can get a nice smooth finish.

The angle grinder is fitted with a sanding flapper wheel – this is excellent for finish trimming and cleaning up welds etc – available in different grits, I’ve pretty much stuck with a 120 paper as it gives a clean finish.
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]]> AllanB https://www.kiwibiker.co.nz/forums/entry.php/968-Slowly-getting-there-11-7-09 28.6.09 hurt my ears..... https://www.kiwibiker.co.nz/forums/entry.php/945-28-6-09-hurt-my-ears Sun, 28 Jun 2009 11:01:21 GMT Well the right pipe is well on it's way. I've made a mounting bracket and it's welded on, the joiner pipe is complete and welded. All that's left is the alloy end cap, and I am going to fab up a nice little alloy cover to hide the exhaust clamp and it will zizz it up a bit visually (a nice contrast with the black) :sunny:

Anyway - fitted it was too tempting not to fire it up, even if I only had one new pipe and one stocker on :blink:. Sounded good :Punk:

Then I popped off the end cap, extracted the core and all packing, leaving me with a big open ended megaphone ........ the engine was warm ........ I pushed the starter ......... and I hurt my ears :laugh: Needless to say all packing will be returned! ]]> AllanB https://www.kiwibiker.co.nz/forums/entry.php/945-28-6-09-hurt-my-ears Sneak Preview https://www.kiwibiker.co.nz/forums/entry.php/912-Sneak-Preview Sun, 14 Jun 2009 07:58:37 GMT Some progress today. A bit of work on the right side midpipe allowing a mock-up to wet my appetite.
Held together here with a bungie cord and duct tape - pretty sure that's what the pros do when building them :shifty:
Note the seat is just sitting on top and not slotted into position thus sitting a bit high.

After seeing this in position I've another idea for the alloy end caps......:laugh:

Next step complete the mid pipe, tack it together and fab a mounting bracket.

Then start on the other side ........:doh:
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]]> AllanB https://www.kiwibiker.co.nz/forums/entry.php/912-Sneak-Preview Progress - well a little! https://www.kiwibiker.co.nz/forums/entry.php/910-Progress-well-a-little! Fri, 12 Jun 2009 06:50:12 GMT 12.6.09

Not much progress - not much free time in the shed lately. I've basically finished the db reducing inserts - picture shows one and a shot of it inserted into the 51mm outlet. The card on the end is another end cap experiment.

The reducer pipe is 35 mm and extends into the inner perforated core. If it is too quiet I just need to lop a few cms off the end of the reducer :niceone: or depending on volume remove them.

They will be held in place by a small bolt - I'll not drill this hole until it's mounted as I'll have the bolt at the top is it's less visible when fitted.

The next step is to remove the stock pipes, mock mount the new ones and fabricate up some muffler mounting brackets. The it's the intermediate pipe.

A trip is planned to see DadB this weekend to discuss the alloy end caps - he has a metal lathe and I'm sure he needs a wee retirement project :niceone:
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]]> AllanB https://www.kiwibiker.co.nz/forums/entry.php/910-Progress-well-a-little! Muffler update https://www.kiwibiker.co.nz/forums/entry.php/871-Muffler-update Fri, 29 May 2009 08:02:09 GMT Well a day off to extend the Queens Birthday weekend has seen some progress on the pipes. Not much as I went for a ride - a cold one it was only 8 degrees! The cones have their end cap inserts sorted and the outlet pipe has been welded in. These caps will be either riveted or bolted to the main... Well a day off to extend the Queens Birthday weekend has seen some progress on the pipes. Not much as I went for a ride - a cold one it was only 8 degrees!

The cones have their end cap inserts sorted and the outlet pipe has been welded in. These caps will be either riveted or bolted to the main cone. However it's just occurred to me I could arrange 3 internal bolts that would be hidden by the end cap.......hmmm (sounds fiddly!)

You can see in the picture where the core inserts in to the outlet. The inlet is a tight slip fit and the intermediate pipe to the muffler will be a fit to the inner core.
I'll be able to wrap the core in baffling, pack the rest of the cone around it and insert the end plate/outlet ensuring the muffler is well packed.

The small pieces with the rounded ends are the start of decibel reducers and need a small length of 35mm pipe to be welded to them - these are a neat fit inside the outlet and the smaller 35mm pipe will go inside the core. This will quieten it down and add a bit of back-pressure to the straight through system.

The other bits of pipe are: curve - the intermediate pipe will be cut from this as it requires a slight bend to align in the manner I desire. Smaller pipes with flared ends - these slip over the stock Y pipes and will be joined to the above intermediate.

Brackets are required for the cones - these will need to be sorted with the stock pipes off.

Finally there's a cardboard mock-up of the proposed alloy end cap.

Plenty of fiddling to go yet.
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]]> AllanB https://www.kiwibiker.co.nz/forums/entry.php/871-Muffler-update 7.5.09 https://www.kiwibiker.co.nz/forums/entry.php/829-7-5-09 Thu, 07 May 2009 05:38:32 GMT 7.5.09
I've arranged the making of the removable end plates today. Priest Sheetmetals will make these as well - I could muck around with a hole cutter, jigsaw and tack weld it, but they have all the gear and will do it 10 x faster than I could in my shed.
These plates will fit into the rear of the cones recessed 15mm so they can be bolted or riveted in place. Each end-plate will have an outlet and internal collar that will slot over the muffler core holding it in position but allowing the removal of all internals for 'noise adjustments' and repacking.

The ends will be finished with a turned alloy ring (hello Dads lathe) that will cover the above plates.

The cones and joining pipes are going to be black, and I'll fabricate a short polished alloy or SS heat shield to cover the joiner.

The total budget for two finished pipes is $400........... ]]> AllanB https://www.kiwibiker.co.nz/forums/entry.php/829-7-5-09 Horny Pipes https://www.kiwibiker.co.nz/forums/entry.php/826-Horny-Pipes Tue, 05 May 2009 10:08:30 GMT Well I've had the Hornet a year and a half and I've made a few alterations. Next on my list is mufflers. I've already 'opened' the stock mufflers to enjoy a few more decibels but my primary interest now is a different look.

It's all on a tight budget supported by a small tax return (in theory - they have not paid yet!), thus purchasing aftermarket muffs is out. And I am after something a bit different.

So phase one has been to have a pair of steel cones rolled. Dimensions are 50mm inlet, 115 mm wide at the rear and 500mm long. They are looking sweet -a great job by Priest Sheet Metal in CHCH.

I've purchased a set of louvered cores.

More parts to come before I start tacking it all together.

Still fluid on the end caps - alloy maybe or another idea brews - I'll see a metal spinner later this week to test that one.
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