Author Topic: Bundy project Now called lighteneing/modernization  (Read 2163 times)

Online gregjet

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Re: Bundy project that has no category ( yet).
« Reply #40 on: October 26, 2016, 07:46:30 PM »
Mr Biggz:
Glassing (etc) I have been doing a long time ( started building surfboards in the late 60's. Built boats, boards, motorcycle bashplates, side covers, belly pans , fairings, seats etc etc. over the years but I am NOT a professional.
I have been working with carbon fibre since the price has come down to a "OK" price. BTW , be prepared for it to drop even furthur. The chinese have developed a new very fast efficient carbon fibre manufacturing process. 
Innegra in a new VERY interesting fibre. A woven polypropylene. Lighter than glass and kevlar ( not as light as carbon), more compliant lay up than any other cross woven fabric, almost as strong as carbon and kevlar, impact resistance almost as good as kevlar, and cheaper than ALL of them. Epoxy preferred resin. Best for non finished layups or between a fibre that can be finished. Almost as strong as carbon BUT doesn't shatter like carbon under impact. Still experimenting with it. Strong but not extremely stiff though.
MR72.
In reality as this is a modernization project I really SHOULD be FI'ing it. It is just too expensive. I use to race an ER6 and the biggest problem would be getting a fuel pump into the tank. The fuel pump is directly controlled by the ECU so matching issues will also be a problem. The squirter also has problems  beside price. I considered making a single throttle body and a plenum chamber feeding both cy, but the huge intake valve timing overlap would make for a set of problems for flow with a single injector.
« Last Edit: October 26, 2016, 08:08:02 PM by gregjet »

Offline Mr. BIGGZ

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Re: Bundy project that has no category ( yet).
« Reply #41 on: October 27, 2016, 05:58:25 AM »
Mr Biggz:
Glassing (etc) I have been doing a long time ( started building surfboards in the late 60's. Built boats, boards, motorcycle bashplates, side covers, belly pans , fairings, seats etc etc. over the years but I am NOT a professional.
I have been working with carbon fibre since the price has come down to a "OK" price. BTW , be prepared for it to drop even furthur. The chinese have developed a new very fast efficient carbon fibre manufacturing process. 
Innegra in a new VERY interesting fibre. A woven polypropylene. Lighter than glass and kevlar ( not as light as carbon), more compliant lay up than any other cross woven fabric, almost as strong as carbon and kevlar, impact resistance almost as good as kevlar, and cheaper than ALL of them. Epoxy preferred resin. Best for non finished layups or between a fibre that can be finished. Almost as strong as carbon BUT doesn't shatter like carbon under impact. Still experimenting with it. Strong but not extremely stiff though.
MR72.
In reality as this is a modernization project I really SHOULD be FI'ing it. It is just too expensive. I use to race an ER6 and the biggest problem would be getting a fuel pump into the tank. The fuel pump is directly controlled by the ECU so matching issues will also be a problem. The squirter also has problems  beside price. I considered making a single throttle body and a plenum chamber feeding both cy, but the huge intake valve timing overlap would make for a set of problems for flow with a single injector.

Thanks for the write up and education on glassing. I have a better understanding of it now, I wonder what the Chinese came up with, as it pertains to Carbon Fiber manufacturing.

Offline mr72

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Re: Bundy project that has no category ( yet).
« Reply #42 on: October 27, 2016, 12:26:51 PM »
In reality as this is a modernization project I really SHOULD be FI'ing it. It is just too expensive. I use to race an ER6 and the biggest problem would be getting a fuel pump into the tank. The fuel pump is directly controlled by the ECU so matching issues will also be a problem. The squirter also has problems  beside price. I considered making a single throttle body and a plenum chamber feeding both cy, but the huge intake valve timing overlap would make for a set of problems for flow with a single injector.

Yeah no kidding. a 180-degree twin is going to basically require two injectors but you might get away with one throttle body, one TPS, etc. But that'd be a microsquirt project, so you'd have to work out everything regarding fuel mapping, probably add an oxygen sensor, etc.

As far as putting a fuel pump in the tank, I don't think that's such a big deal. That's an electrical part that if you were into getting the project to work should be pretty easy to deal with, you just mount it barely below the tank, likely making a bracket that bolts where the tank petcock goes so you have a fixed length of hose of like an inch from the tank petcock to the fuel pump (and a T junction).

The hardest part of a FI conversion FOR ME is welding up the exhaust to add an oxygen sensor and then tuning the ECU mapping. That, and if you have to machine in a notch on the intake cam to trigger the ECU. Either you start with FI from a 180-degree 500cc parallel twin like a CB500F that runs in closed loop so you can sort of drop it in and go, or you have to go through a year's worth of mapping programming with a programmable ECU like a microsquirt. If using ER6n FI you'd have to probably adjust the fuel pressure anyway (thus the OE fuel pump is not as important) to keep it from flooding on cold start or running way too rich in other open-loop conditions like WOT.

Like I say, easier to just replace the bike.

For a half a minute I thought about whether something more dumb could be done... steal TBI from a tiny 80s car like a Toyota Tercel that is all analog using a vane-type AFM that's easy to modify, no TPS at all, can run all day long in open loop and truly the only thing to adjust is fuel pressure. But you run into the 180-degree-twin issue. You'd just have to fab an intake and source a throttle body. But I'm not sure an '80s automotive FI is really any improvement over '90s MC carbs.

In the end I decided I needed new skills and dug into learning how these carbs work. Cheaper and easier in the end.

Online gregjet

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Re: Bundy project that has no category ( yet).
« Reply #43 on: October 27, 2016, 09:40:46 PM »
Adding an "O2" sensor I have done before ( on an ER6N exhaust as it happens). Turn an adapter with a 18mm male thread for the pipe and a 14mm female thread for the 14mm sensor. Tap the pipe, with sealing compound on the thread and land screw it in. Spot weld the adapter to the pipe. Doesn't need a  full seal weld ( I ain't no boilermaker unfortunately).
If you use a sufficient volume plenum you should be able to use a single injector throttle body and use the pulse timing to meter for a full two cycles ( I think). Definitely only need one TPS  no matter which way you go.
Which ever , I can to a similar conclusion that it would probably not be a viable addition to the project. Not worried about "getting a better bike" , as the whole point is playing with this one is to see what I can do. I have other bikes to ride. This is my guinea pig ( more techically a cavey...)

Offline The Buddha

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Re: Bundy project that has no category ( yet).
« Reply #44 on: October 30, 2016, 03:29:40 AM »
I wonder if anyone has tried lifting one out of a Honda CB500 or the 300 even.
But I cant imagine the varying temps of an aircooled motor would help.
Cool.
Buddha.
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Online gregjet

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Re: Bundy project that has no category ( yet).
« Reply #45 on: October 30, 2016, 08:40:32 PM »
If you can get into the ecu and map it on a dyno should be reasonably easy to do using a Honda CBR500 if the 500 is a 180deg crank ( no idea if it is). The GS isn't going to breath as well as the CBR so injector/pump limitation is unlikely. The biggest problem is the intank fuel pump which is an integral part of the EFI. If you can get an extrernal pump that delivers the same pressure it my be fine but modern EFI quite often controls the fuel pumps as well in some systems.
I am pretty much come to the conclusion it isn't economic to pursue.
 Not helped by the fact that the round slide carb kit for the GS500 has gone up 60% in 6 months. so I suspect the carbs are staying.

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Re: Bundy project that has no category ( yet).
« Reply #46 on: May 19, 2017, 02:26:36 AM »
Well finally getting back to this project almost a year after I started it.
Summer was VERY long and ridiculously hot in the shed , then a ton of stuff happened. Well today and yeaterday it rained and stopped me doing all the stuff I SHOULD be doing, so I went back and started fiddling again. Did a bit more work on the lower fairing. Finally added some brackets and clamps for the electronic speedo pickup and wired it in.
A little update. Hopefully more work to follow and get the fairing finished.
« Last Edit: February 03, 2018, 08:58:27 PM by gregjet »

Offline Suzi Q

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Re: Bundy project that has no category ( yet).
« Reply #47 on: May 21, 2017, 11:22:26 PM »
There's a heck of a lot of awesome things going on here for a bike with no direction/category. Digging the lightening.  :bowdown:

Also:

Holy hell! on that tank protector damage.

info on brakes? ty
« Last Edit: May 21, 2017, 11:22:59 PM by Suzi Q »
Deals on Amsoil if you want it. PM me for details.

Online gregjet

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Re: Bundy project that has no category ( yet).
« Reply #48 on: May 22, 2017, 09:00:36 PM »
The tank protector damage is even worse than I first thought. It has been rust converted, zinc painted, painted, started bubbling again. sanded, rust converted AGAIN, zinc painted, repainted and now it is starting to bubble again. I don't know what happened in the first place,but it was nasty.
What do you want to know about the brakes? front disc is from S3 performance so has their logo on it. Don't know the actual manufacturer. Reasonably lightweight but , as yet haven't ridden it ,  performance is yet to be determined. Had to change both discs because they were   way under spec. Rear is a 2nd hand slotted gs500 disc. Not really happy with it but will pass roadworthy. If I don't like it I will get a better lighetr one.

Offline Suzi Q

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Re: Bundy project that has no category ( yet).
« Reply #49 on: May 23, 2017, 01:07:28 AM »
Is the front same as factory, only lighter? How much did it run? I'd be curious to hear riding impressions...I'm a huge believer of eliminating unsprung weight.
Deals on Amsoil if you want it. PM me for details.

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Re: Bundy project that has no category ( yet).
« Reply #50 on: May 23, 2017, 10:01:34 PM »
On forum page 2 is the front discs were weighed but the PB stuff up meant they were deleted. Will repost below. The spacers ( outer right, centre and a spacer to replace the speedo drive) are Al ones I have turned. The speedo cable is of course gone. The forks have been slightly turned down. Most ( not all) of the steel brackets on the front have been swapped for Al ones. Fork internels have been lightened as well ( lighter shorter  springs, Al spring spacers). Small extra weight added as Gold Valve Emulators and the fork brace ( AL carbon fibre sandwich). I will go to a 120/60 front as well which will be very slightly lighter .

Still working on it ( forever?) and it isn't registered yet so it will be a while before I get to ride it. If Sally sells her KTM Duke 690 I will have to hurry up the project so she can have a bike. ( edit 3/2/18: Sally has sold her Duke so project is restarted)
« Last Edit: February 03, 2018, 09:58:28 PM by gregjet »

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Re: Bundy project that has no category ( yet).
« Reply #51 on: February 03, 2018, 09:31:01 PM »
OK project re-invigorated as Sally has sold here Duke 690.
Bottom fairing finished. Will post a pic when I mount it on the bike.
Stick coils from an early ford ( cut shorter and made plug connectors to fit.) used, because they match with the output from the ECU well. Bit clumsy but work well. Had to make some supports to hold them. Wired in using existing low tension wires( with extenders for the time being until satisfied they are working properly, then I will single connection them, Found I had to re-do the connection for the Acewell tacho as signal was wrong. Ended up taking signal from ONE coil from the ECU side instead of the bike's tach signal wire. Made a 1 megohm connector piece to go inline. Again when satisfied i will simplify the wiring.
Works very well and idle is definitely smoother and starts very easy.
Next the fuel pump and simplify the fuel lines and add a quick disconnect.
« Last Edit: February 03, 2018, 10:00:47 PM by gregjet »

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Re: Bundy project that has no category ( yet).
« Reply #52 on: February 03, 2018, 09:34:56 PM »
Pic of the inline piggyback resistor for the Acewell tach signal.

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Re: Bundy project Now called lighteneing/modernization
« Reply #53 on: February 08, 2018, 03:51:53 AM »
Ok the coils work like a beauty. Seems to run much smoother at idle, revs out easy and clean ( no load), returns to idle without stalling and will now idle at a ridiculously slow rpm, if I wanted it to.
Next. Fuel pump:
All fuel lines removed. All vacuum lines removed. Fuel tap removed.
Tank petcock removed.

Right start with the fuel tank petcock.
Disassembly showed the o ring was perished. The upper seal was useable. Because I am only using one of the outlets I checked the flow through and found BOTH galleries are partially restricted. Wht put 8mmID lines on a bike and have a tap that only is 40% of the crossection? See the pic down the tap. Drilled it out to consistant bore. Realigned the fuel filter the other way around so it flows to the bottom ( no reserve).
Turned down some brass to make a hat plug and spoldered it in to the shorter outlet.(pic)
The O ring was stuffed (See pic) so replaced it with an Oring from an automotive air conditioning set. The Repco guy assured me it was fuel resistant. IF you know otherwise please post here and I will chuck it and go hunting again ( no easy to find apparently 10mm id, 14mm , 2mm thick od, round cx).
Cleaned the grooves and channels and replaced and teflon lubed everything. Some liguid gasket on threads and mating surface.

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Re: Bundy project Now called lighteneing/modernization
« Reply #54 on: February 08, 2018, 04:05:48 AM »
On to the fuel pump and lines. Because the outlet for the tank and the carb inlet is 9mm nom. and the pump is 2x7mm nom. I made 2 reducers the mainlines will be 7mm( id). Because the pump draws a neg pressure and pushes a positive pressure I suspect I can run the smaller lines sucessfully.

 The pump is from a yamaha Vtwin 650 and/or a Kawasaki 650 V twin cruiser, with very similar carbs , so I am pretty sure it should be a good match. I mounted it as high as I can get to reduce static pressure when no running. It is up under the front of the tank. Gets airflow from the front there as well to keep it cool.

I used pressure fuel line in all spots and screw clamps ( not plier clips).
I have removed the air solenoid so I used the switched line of that for the relay signal. Wired the power side direct to the battery and the switched power side to the pump. Common earth for the switch and the pump. In the pic the pump power is the bright yellow one. It is the only long wire run added. The pump only draws 2 to 4 amps so all should be fine.

Tested it with a funnel and it primes and switches off on on with demand flow fine. Have to put the tank line with quick connect on next.
 
« Last Edit: February 08, 2018, 04:08:25 AM by gregjet »

Offline mr72

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Re: Bundy project that has no category ( yet).
« Reply #55 on: February 08, 2018, 02:21:24 PM »
Stick coils from an early ford ( cut shorter and made plug connectors to fit.) used, because they match with the output from the ECU well.

By "ECU" I presume you mean the stock Suzuki igniter? Just verifying you didn't replace that with some later-bike ECU.

I'm very interested in this, sounds like you put coils-on-plugs, which is an awesome idea. But getting them to mount sounds tricky to me. Can you go into more detail about exactly which COP you used? you say "old Ford" but maybe you can give a Ford part number for x-ref? Like, I can go to Autozone and buy a pair of them and do the mod on my bike, but I have to know what to buy.

And you say "matched the output of the ECU" but how do you know that? The igniter just switches 12V to ground, right? So it would seem any ordinary automotive coil-on-plug from >2000 cars would work just fine. And I also assume you mean that you are batch-firing them, wasted spark, right? Jumpering the coil output? How are you controlling dwell? Or did you bother checking?

Sorry for all the questions, but this is something I'm very interested in doing.

--EDIT:
Noticing all of this aluminum-angle fab you are doing, maybe you would be interested in investigating "aluminum brazing" which might clean up some of that work. I am looking into trying it myself. Seems if it's not heavily structural it could work well especially as an alternative to filling gaps with something like JB Weld (which in my case never seems to work nearly as well as advertised). Just an idea. I mean, welding aluminum is one thing, but for the cost of a $15 torch and a roll of aluminum wire you might get 90% of the benefit.
« Last Edit: February 08, 2018, 02:26:05 PM by mr72 »

Online gregjet

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Re: Bundy project Now called lighteneing/modernization
« Reply #56 on: February 08, 2018, 08:54:21 PM »
Lots of questions. OK here we go.
I call the electronic unit an ECU because on the bikes with only one pickup the "ECU' does all the spark control for both cyl. And it uses the Throttle position sensor as a input variable. It isn't just a simple igniter ( in my book).  The second cyl firing is calculated not triggered. All the timing and timing mod is done electronically. The pickup is relly not much more than a crank position sensor ( ok it reads the rise/fall slopes as well for advance )usually I don't know for certain on this bike.

No idea which Ford they are on. I did it a while ago but I think I researched the resistances and  coil multiplier and this type of CoP was the closest to the stock new coil. I know later coils have a lower multiplier ratio, because they use steeper trigger slopes. and don't work as well ( read not well at all). Also these are TWO wire only so don't have the extra circuitry for the later control.  I bought it from an autostore, so no idea what vehicle it fits ( they would be listed for Aussie vehicles anyway). I had a good look, but can't find the stuff that came with the coils, though I suspect any part number would be an instore part number as it was the stores own brand. What I can tell you is that as far as I know these are the only coilover that LOOK like these. It wasn't my preferred shape as it interfers with the frame and I had to mod the lower insulator and make my own spark plug connector ( turned down a Al rod and drilled a hole basically). IF you can find a better thinner shape, one it would be a big improvement, but because of the angle and the proximity of the frame it can't be too long.

Remember in a car most CoP's are supported by the engine ( usually the tappet cover) and especially nowdays are bolted in so it pretty much goes with the territory that some sort of support will be needed. They are in later motorcycles as well.
 If I am happy with them when I can finally put some load on the engine, I might go looking for a better thinner set with a spark end conmector that uses the bare threads not the little screwon cap.

The "igniter" doesn't just switch to ground. It puts a multiple high transient waveform through the coil as far as it know. It also does the spark mapping. As it uses the TPS, I suspect it also changes other waveform envelope stuff ( who knows). I know on some early 2000 injected SVC650's that the ecu also retards and reduces the number of pulses per individual spark  cycle at 5000rpm for noise reduction reasons ( amongst other stuff that makes it a performance problem including EFI changes). This GS is from around the time that Suzuki was doing this, so who knows.

I discovered an amazing Canadian Al "brazing" rod recently that I intend to experiment with ( HTS2000).  Much of this bike is prototype stuff and proof of concept, so will get an improved version at a later time ( yeah sure...). I use Al cause it is light and easy to work with mainly.  Often I will make Carbon fibre /innegra stuff for brackets, but for the fuel pump, it will be Al to act as a heat sink.

If you do it , post. I will be very interested to see how others go about it. Especially if you can find proper Coil overs as opposed to my "coil on top". My biggest worry is they won't handle the high revs of a motorcycle and may leak or have some sort of unwanted resonance electrically once the revs are up.

Offline mr72

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Re: Bundy project Now called lighteneing/modernization
« Reply #57 on: February 08, 2018, 09:38:50 PM »
Great stuff, thanks for the explanations Greg.

I built my own coil-on-plugs rig for my Miata which worked brilliantly up to 7500 rpm or so where the rev limiter kicked in. However, the really had too much dwell which was supposed to be a real problem, predicted to cause the COPs to die an early death due to heat. IDK, I put about 80K miles on them revving it to the limiter nearly every gearshift and never had any problem at all, but who knows? It was also wasted spark 2x2 design. Those COPs were from a Toyota Corolla, chosen simply because they fit the spark plug wells in between the cams on the Miata cam cover. I used an aluminum plate with bolts in it connected between the cam humps to hold them down. Literally the job of affixing them was far and away the hardest part of the entire project... initially i JB-welded bolts to the cam cover and that worked for about a month...

Anyway, I have a couple of old COPs from another Mazda in the garage, might fiddle with them, but the reality is on a GS500 as you have found there simply isn't nearly enough clearance to fit an auto COP in there, but that's because (as again I'm sure you've found) the spark plug wells in twin-cam automobile heads (and >2cyl motorcycles) tend to be deep holes and most of the length of the COP is simply to extend the electrode down to the plug. I would think simply finding the lowest-profile coil on plug (shortest) would be preferable. But I'm not sure the value of COPs is enough to counteract the packaging constraints of cramming them on the GS500's cylinder head.

You have a Mk2 ('01+) GS500 I presume; I'm not sure how the igniter fires the alternate cylinder but if I was designing it, I'd figure that the output of the signal generator is a sine wave as it rotates so I could produce top and bottom side pulses by DC-coupling the signal generator (ground and +v) and use a dual comparator to trigger at the low and high side a few degrees before TDC figuring the sinusoidal voltage will pretty reliably be the same at the same angle on every cycle. Anyway, the rest, I have no idea. I'd have to put one on an oscilloscope and reverse engineer it. But as simple as everything else is on a GS500, I would have guessed it's a simple switched output. I guess the igniter in the Mk2 is different in a lot of ways from the Mk1.

Again, thanks for the discussion, very interesting. I'm especially interested because you suggest the idle can be set very low which to me is a good thing since it's more reliable to meter fuel at idle with the throttle plate completely closed.

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Re: Bundy project Now called lighteneing/modernization
« Reply #58 on: February 09, 2018, 02:49:10 AM »
The total length of my CoP's was MUCH longer but the majority of these ones was soft polymer. I shortened the spring and clip and cut the soft pieces down. Fits tight but fine.  The biggest problem is all the weight is at the top so I had to fabricate a bracket to hold the tops. Again used Al becuase it can act as a furthur heat sink.

The "dwell" from the ECU is not a simple single wave. As far as I know it is a series of high transient pulses ( not quite square wave, not quite saw, but definitely NOT sine wave). It alows much high spark energies from lower input voltages and currents,  and you can tailor the spark duration by expanding the envelope ( I think that is how the Suzi one works). It a 05 with an 2011 motor (put in by previous owner). So there isn't a "dwell" as such although older type dwell meters will measure it as a long dwell, as they tend to measure the entire envelope not individual pulses. A scope will show a totally different shape. No I don't have a scope. Wish I did. I believe you can get a USB one for a pc/laptop and prob even for a phone nowdays.

The ecu on the later models uses the reluctor on the crank end as a crank position reference only for each cyl .  ALL other spark mapping is done by the ECU. I am guessing there is a waste spark because there is no cam input to know when the crank is on a power stroke. With the cam timing on this bike it would in the exhaust stroke anyway so irrevelant. Thinking about it the fact that the pulses are asymmetric would allow the ECU to know when to fire the second pulse. Long relative duration interpulse fire the cyl one, short duration interval fire the cyl 2. ( I stand to be corrected by someone that actually knows for certain). Could do it with a simple logic gate.

The voltage rise will be faster as the rpm increases, as the reluctor goes from, away, to close, faster. That makes the magnetic field rise faster. Honda used that fact to drive the advance on it's Vt 250  in the 80's. The greater the transient, slope the higher the secondary voltage output . That's why the square/saw wave output pulses can drive a high voltage with lower input coil current. It is also why coil overs turned up. The higher frequencies ( effective) means more electro magnetic leakage. Put the coils and spark"leads" on top of the plug and stuff all places to leak ( infact the coil around the plug ceramic helps produce a positive feed forward ( I think) in the plug electrode wire. I am happy to be corrected but that's what it looks like to me.

I didn't set the idle as low as it would run. Past experience says that usually makes for choppy throttle at low rpm to off idle. Set it at factory. Only motorcycle I ever set lower were off road and trials bikes ( dead idle)