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Discussion Starter · #121 ·
I looked but can't find if the factory spec is crank or wheel power.
Here is the comparison of my torque curve overlaid on a injected 05 modle with efi k&n filter and slip on. Should be better now I have the throttle opening all the way after fiddling today

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the only figures that matter are the ones you have for your bike. without a before run the afters are a bit worthless.
 

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Discussion Starter · #123 ·
the only figures that matter are the ones you have for your bike. without a before run the afters are a bit worthless.
I am already keen to get back and try again now that the throttle is opening all the way.
But I will ride it around a bit while I save Some coin.
 

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Impressed as **** (y)
but I don't think you want much filtered when you are experimenting with a carburetor and the intent of the dyno is to trouble-shoot the tuning, not impress anybody with #'s at this point imho.

We had so much snow here last night it finally ended my 2020 riding season, lol unless I want to ride plowed township roads on a studded KTM
 

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Discussion Starter · #125 ·
Impressed as **** (y)
but I don't think you want much filtered when you are experimenting with a carburetor and the intent of the dyno is to trouble-shoot the tuning, not impress anybody with #'s at this point imho.

We had so much snow here last night it finally ended my 2020 riding season, lol unless I want to ride plowed township roads on a studded KTM
I didn't know about the filter at the time, I left it up to the dyno person, but I it may have been because it was very hot and humid. This is new to me.
Next time I may have to get a printout with and without filters
Thanks for the feedback and support
 

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Discussion Starter · #126 ·
Ok, Idle is still an issue but not cylinders cutting out or manifold imbalance.
Although I knew it I hoped I wouldn't have to address it. The throttle plate can spin around in the bore of the throttle body. I can see on a larger engine it may have been ok.

So it is a fraction, small even in the closed flat position to much air get past and when the mixture is correct it idles too fast.
I can get the idle speed correct by running rich but I want it correct.

So my mission I have chosen to accept, is get the throttle plate sealing at an appropriate angle,

The throttle plate is not just a flat plate so I need to work with what I have.
I am thinking of running lead/tin solder around the edge fitting it on the shaft and tapping it closed, filing where needed and hoping the soft solder will also conform a bit.

Any other ideas are welcome feel free the throw ideas at me, Thanks
 

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Discussion Starter · #127 ·
Today I soldered around the throttle plate and filed it to shape it now snaps closed to about a 3 deg angle. No sticking and although I can see light around most of it when held up to the sun I am happy with the fit.
Bolted it on throttle "closed" and it idle steady 800 rpm. (win)
I have noticed the idle air by-pass doesn't shut all the way off when screwed in, but like the throttle plate I will wait and see if that is a problem or not. No mixture checks have been done yet
My new Chinese Reg/rec has died but good news is the stator still tests ok. Maybe the dyno killed it.
The Li battery runs out of puff scary quick with no charge going in and the head light always on.
I am thinking of getting a Honda cbr unit
 

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I thought the throttle plates were at 27 degrees when fully closed? (but it's been a while since I did an SV)
 

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Discussion Starter · #129 ·
Next stage. on my sv650 cafe racer all mixtures seem ok (will dyno again before cam swap.)
Getting really frustrated by intermittent fuel cutting out. when I have previously checked the vac fuel pump it has looked ok but today it did it again and the pump was not working.
I believe a new vac pump should work reliably on my custom intake system but, I have an electric pump so despite wanting to retain the standard pump that's the job at hand.
So the pump I have fits well, I have made a cross shaped bracket which mounts where the stock pump bolted to the frame using the stock rubbers and bolts.
The pump runs inside the right frame in the standard place.
Next the bit I dreaded finding 12v to run the pump.
After sliding back the rubber boot on the harness I found an unused 2 wire connector one wire black/white -earth and orange/yellow + 12v ign switched
Looks like its for carby heating not used here, Perfect

So tomorrow it should be done and I will post how it goes.
 

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Discussion Starter · #130 ·
Electric fuel pump in and running well, I can do some more tuning now.
I see no reason this would not work with the standard carbs on the gen 1 sv650.
 

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Discussion Starter · #131 ·
With the electric pump it is running consistently and I thought it was running a bit rich arround 5000rpm light load riding up hills,
But it turned out to be lean, so until the next dyno session I have richened the full power adjustment a bit, which impacts the whole range from barely at idle more as the throttle opens.
So it feels very strong now the dyno will tell me if there was a better way to fix it.
I have changed a lot since the last dyno including drilling the spray bar in the TB and made new guts for the muffler to reduce noise. So I can only hope I am still improving things, it is riding very well.
 

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Discussion Starter · #132 ·
I had some time today so I made my plasma ignition leads. Not fitted yet I will set up a test to see if they work first. I think I have made them correctly but it's my design and at this time unproven.
But hopefully it will compliment my single throttle body conversion.
 

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Discussion Starter · #134 ·
Hopefully I will get some more dyno time 24/6.
The "seems" to be riding really well so incase not much tuning is needed I am making a list of things to test back to back e.g. air filter on and off, Plasma ignition leads on and off, balance tube and no balance tube.
All tests have been done so far with the TPS wound to full throttle position ...connect or leave as is.
Also the intake runs really cold maybe I could try it wrapped and not wrapped.

Are there other tests anyone can think of that may help?
Should I ask for results in Din HP or some other?
 

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Still running the single “fish” carb? if that’s what it’s called. Pretty sweet what your doing I think. Even if you can match stock power no one else has what you have(y)
 

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Wouldn't a direct coil on plug ignition system make the plasma wire concept totally obsolete?
... I don't see the engine producing any more power because of a slightly brighter spark, but you shall see if you're going to all that effort, keep us posted.
 

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Discussion Starter · #137 ·
Wouldn't a direct coil on plug ignition system make the plasma wire concept totally obsolete?
... I don't see the engine producing any more power because of a slightly brighter spark, but you shall see if you're going to all that effort, keep us posted.
Yes I don't expect much (nothing power wise but maybe cleaner plugs) from my leads. even a race setup with plasma ignition usually only gives about 1% more power. I have seen reports of up to 8% but they probably had other issue before.
 

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Discussion Starter · #138 ·
The weather was very average this morning so rather than ride 1/2 hr to the dyno in rain I have rescheduled the test session and spent about 6hrs, making, fitting and wiring the TPS. Since the cdi was designed to work with the tps, I think it's the thing to do.
104766
 

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Discussion Starter · #139 ·
Just got my e-marked bar end mirrors, so I pulled off the "better looking" 75mm mirrors and banged on the new legal sized mirrors.
On a custom bike it doesn't feel right but I don't want to attract the wrong attention
 

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Discussion Starter · #140 ·
Cold is good for an intake but despite running well once started, the weather here has gone single digits on the Celsius scale.
The result is wet plugs that won't fire up.
So I am going to wrap the centre of the manifold with silicone tape holding a wire wound resister against the manifold to heat it a bit on start up.
I've never done this before so comments are welcome.
And if it needs it, I will run a pipe from between the heads for warning once running.
Also I have ordered a 10mm Colortune kit to help get bottom end mixtures better, so I am looking forward to that arriving.
 
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