RGS Carbs Choke thingys

Hey Rob,
Gave notice here in Ukraine 2 weeks ago but committed to stay until they found a replacement.
Probably be 8-10 weeks, hopefully sooner.
Not accepting anymore contracts at the moment though have 2 good offers, one in Romania and one in Kyrgyzstan.
Tempting as both are rotational, 5 weeks on, 5 weeks off.

May do some short jobs next year, wish to have the rest of this year off though.
Have 7 engines to build, 25 bikes to restore, untold heads, cranks, carby sets, workshop extension, Dyno room to build, Dyno stand to build, your GSXR wheel conversion plus 3 others, Solidworks courses to attend, race engines of course.
Go for a ride with Max for a change.
Get a headache just thinking of all I have to do.
Should stay here, is easier.  :D

Red

 
Red , I'm about to start building my house and the thought of that is starting to freak me out. Need to get the Motodd sorted first otherwise I won't have time. I aim to have it running before the year is out. Heaps to do!!
Sounds like you need to take some time off from drilling, hang in there, it all comes out in the wash :-\
 
Rob,

34mm exhaust with a 41mm inlet is a good match, stock in 1000SFCs.  Is also what the works 180? racers were using back in the day!

Larger inlets will require quite a bit of recession in the head, compromising compression and adjusting range, larger exhausts are useless... :D

By all means, open the ports to 36mm, widening at the guides and leaving a distinct hump on the floor where the port enters the combustion chamber.  Don't blend the bottom of the port right down to the valve seat, fucks up flow big-time!

piet
 
Hi Piet,
My head is already finished so that's the way it's staying, only mods done, new guides, valve grind, ceramic coatings and openning up Red's angled inlets from 36-32 to 36-34 and inlet port opened to suit, as recomended by the engineer. He said 36 would be too much for a 39mm valve so I left that to his superior knowledge. I'm not after rip snorting performance, even in it's previous state of blowing smoke and showing signs of 170,000kays of thrashing, [if it didn't leak oil and have a stripped stud I would still be riding it] It was still damn quick!!. Now with Ross h'comp pistons replacing flat tops, lashings of ceramics, Mikuinis and Sashe ign I'm sure it will be more than enough for me.
My original question was regarding your thoughts about inlet size for a 39mm valve with 36mm mikunis. I had asked the engineer to open up the stub to 36mm[from 36-32] and port to match and he thought that was too much and said 33~34mm would be better, and I ended up with 34mm. He did fuck up slightly, when I got the head home I notice he's refitted the angled stubs pointing up instead of down and when I turned them around they don't quite match the inlet port so I'll smooth out that transition before refitting the head.
I now have to decide wether to split the [virginal] cases to replace the g'box bearings or just throw the head and barrels back on. I don't think there is any issues with the bearings apart from the fact they've done 170k. Might just wait another year or two and do them when I get Red to redo my crank. My bike is in enough pieces at the moment, do I need to create more pieces??
And I'm a "if it ain't broke don't fuck with it" sort of guy anyway.
Cheers
 
redax5 said:
May do some short jobs next year, wish to have the rest of this year off though.
Have 7 engines to build, 25 bikes to restore, untold heads, cranks, carby sets, workshop extension, Dyno room to build, Dyno stand to build, your GSXR wheel conversion plus 3 others, Solidworks courses to attend, race engines of course.
Go for a ride with Max for a change.
Get a headache just thinking of all I have to do.
Click to expand...

Don't forget Maxs Corvette brake conversion....

sorry  :-X
 
hey Drikko, thanks for reminding me, I had forgotton about the Corvette
have a Mass Flo Fuel Injection system to install plus the Willwood 6 pot front calipers, 4 pot rear calipers, new vented rotors and the new twin unit master cylinder set up so we can get rid of the power booster which does not work with current high lift, high duration camshaft that we are running.
sort of looking forward to working on the Vette again, not touched that toy for years

plus we have to redo the pool fencing to conform to Govt regulations so we can get the pool registered before November or be fined $14,000.
I made all the fencing few years ago and spaced the vertical rails at 120mm but then they bought out new rules that says max spacing is 100mm so I have to take the whole fence down, cut it all up and then reweld it to correct spacing
what a load of crap
 
Your not alone Red,my sister is doing a reno and made the mistake of using the Council inspector instead of a private certifier,and surprise surprise there 15 year old and previously passed pool now has a problem and following the regs to the letter would be impossible to make comply without an insane redesign,thankfully there was a compromise.BTW all those stainless wire handrails,10s of thousands of them are now illegal,the reg now is a specific weight is hung off them and they cannot sag beyond a set dimension,thats physicaly impossible to tension them enough to comply without snapping them or pulling the posts out,wonderfully world we live in
 
breganzane said:
Rob,
Just put the top end back on and ride! :-)
Cheers
Steve B
Click to expand...

Hey Steve, ok you've convinced me, the cases can stay virginal!!, Once I get this 81jota off my work bench I'll start on mine. Going to check the cam timing while I'm at it.
Then it just comes down to finishing all the carbon bodywork, bit of welding on the frame, throw some paint at it, slot in new wheels,disc,calipers [no preasure Red :)]
Can't do any painting till the sun comes out so that'll be December/January
Some rewiring will be need to be done then it should be ready to go for a ride, I'm aiming for the Northcliff run end of march!
 
You have to register your pool??  :o

Gawd almighty, I think Australia has taken the nanny state rubbish to extremes not seen anywhere else in the world. If you don't have kids, then the only purpose for the fence is to stop trespassing brats from falling in, serves 'em right I reckon (presumably any visiting kids will be supervised). You'll probably have to but a bloody fence around your bathtub next.

There's a pothole in my street with a puddle of water in it. I better call the council and tell 'em to fence it off.

Grrr
Cam

 
Here is my swimming pool and no fucker has told me to build a fence around it and I'd like to see them try!!

P7120095.jpg
 
is that a black snake you have in your pool there Rob ?
had a couple of red bellied blacks in our pool over the years

Cam, not only do we have to register the damn pool, at a cost of course, we then have to have it re-inspected every 2 years after that, at a cost of course
and I agree on the kid status, it isn't like we have hordes of the little mongrels running around everywhere
not being a fan of children at all


 
Sometimes you can get around regulations by calling a spade a shovel.
You could try calling it an emergency water supply for fire-fighting.

Rob, it looks as though you have the beginnings of a fence IN your pool.

Cheers,
Cam
 
Rules and regulations!!!! How the fuck did we get by years ago without them??
Nah not a snake Red, 1.1/2" poly pipe leading up to my header tank, though I do see Tiger Snakes in the dam from time to time. In all the surrounding teatree I reckon there'd be a shit load of tigers being their favorite enviroment feasting on their favorite food, frogs.
Cam, the posts I put in years ago thinking I might want to build a deck over the water sometime, when I've got nothing to do!!
 
So, jets changed, carbs cleaned, attached to bike and it starts first press and sounds so much crisper.

Need to take it for a run to check the mixture....

Question? Why do people always over jet when fitting a performance pipe? In my strangely non-mechanical mind, if the engine is breathing better isn't it more efficient therefore not needing the huge jets?

Confused of Yorkshire.
 
Dear Confused of Yorkshire

I've often thought exactly the same thing about performance pipe jetting, and I supposedly do have a mechanically inclined brain (at least I have a piece of paper that says so).

If an engine breathes better because of a better exhaust, it will probably suck more air through the carbs. More air means lower throat pressure in the carb which will suck in more fuel through the main jet. More air + more fuel means the mixture should be OK, or at least somewhere in the ballpark. That's how carbs work.

As an example of unnecessary jetting: The previous owner of my Jota put a very non-restrictive 3-1 exhaust on it and decided the jets needed to go up to 135 (from standard 118) and K5 (richer) needles. He also put 4C cams in it but used the A11 cam wheels, so valve timing was all over the place. That's how it was when I bought it. He said the modifications made it go really well, and it has a kick in the arse power band at 6000 rpm. When I test rode the bike, I felt the power surge he was talking about, but it turned out that it wasn't so much an increase in power that I could feel, but a loss of mid-range made the top end feel stronger in comparison. Strange how we can fool ourselves. In reality this "Jota-ised" 3CL engine was putting out less power than a standard 3CL.

After I bought it, I ran it on the dyno and it was running horribly rich. I went down to 125 mains and standard K1 needles and it was still rich.
I then got rid of the wide open 3-1 and put a slightly less noisy (but better flowing) Redax 3-1-2 Laverda style exhaust. Mixture didn't change from the previous pipe but horsepower went up by more than 10%. I've since sorted the valve timing and gone back to 120 mains. Mixture is still a wee bit rich on the dyno, but not enough to worry about (the original 118's would be just about perfect). Bike is running much better now than when I got it. 11 more horsepower at the rear wheel just from basic tuning.

So I guess the only thing you can say with any confidence is that the jetting MAY need to be changed for a different exhaust, but just as lilely not. You really need to re-check the mixture after a pipe change just to see whether any adjustment is necessary.

The other take-home message is always check the work of the last bloke who tuned it. He might tell you a lot of good stuff, but not have a clue what he's talking about.

Cheers,
Cam
 
Cam care to hazard a guess what effect changing from A11 to F1 cams would have on the jetting,the F1 has slighty more lift and I think a lot more duration.Same size hole opened bigger,lift, and for longer,duration.That bit of a thought bubble does my tiny head in.
 
Vince said:
Cam care to hazard a guess what effect changing from A11 to F1 cams would have on the jetting
Click to expand...

My guess is no effect whatsoever. But I could be wrong  :D

Only way to be sure is to measure the mixture before and after. (O2 sensor or dyno runs)
 
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