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Just a heads-up - I'm running a batch of STV Simulators (production SMD board version) and can probably fit in a couple of the SV1K variant - need to know quick
These are likely to be the last I will do - demand is very low. So if you don't get now, probably will not be available after this batch.
Send me PM if interested.
 

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Mine's still working well. The bike puts 107 to the wheel with hacked up airbox, no STVs, full M4, PC3. Mine is the pre-production version, but I haven't had any problems with it. I'm

Any suggestions for an idle adjuster cable that's a little easier to turn by hand, so that I can crank it up for a fast idle when cold, or some other solution?
 

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Wow, I don't see how they can ask $57 for it... seems like a simple part. I guess I'll find a used one.
 

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okay, reviving my thoughts on this now that i have time to work on the bike again... I've done the math: the six holes at 3/8" give a surface area of the holes per plate of .662 sq in. If I cut the STVs from 52mm to 47mm on the edges that gives a reduced area of .602 sq in.

The big question: how much area can i reduce and keep the stock fuel map without it leaning out too much? The indication were that the six holes at 3/8 was too much and it caused lean out in middle RPM ranges. I have a TRE, and i've added 4deg advance on the crank with a factorypro kit, and it has a yosh 2-1 exhaust. I do not want to install a PCIII or other if i can avoid it.

thx.
--Joel

are the STV's perfectly round, or are they slightly ovaled? I was thinking of making some on the lathe so i could experiment without modding the originals. i was thinking that by making them smaller than stock diameter (assuming they're round) by .010-.030 (gotta do some math to get close to what the 6x3/8" hole area is in the drilled ones), i could actually get a progressive opening effect instead of having holes in the middle which are a constant size. Working theory: as the STV is closed, it would have slightly more flow and be ready for the primary plates, and then as the STV opens, it would have the effect of opening at a faster rate, thus helping to maintain smoothness.

thoughts?
 

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Discussion Starter · #89 ·
The big question: how much area can i reduce and keep the stock fuel map without it leaning out too much? The indication were that the six holes at 3/8 was too much and it caused lean out in middle RPM ranges.


--Joel
After running a Wide-Band and A/F gauge it's become obvious the 1K's are mapped F A T and you have little risk of going too lean with STV holes. Removing them entirely won't throw off the mixture enough to worry..and in fact I think it moves it in the right direction. When I was drilling and tinkering with the mixture going by Seat-O-Pants it 'felt' better with a bit of fuel added in the midrange, but this proved in the end to be unneeded and actually way too rich.

My Assometer likes it rich, and going fatter always makes the throttle more responsive at whatever position you check. Problem is they're fat from the get go, and adding fuel going in the wrong direction. After 14K of running happily with the addition of a bit of midrange fuel the pistons and combustion chamber were heavily fouled with carbon. Funny thing was it always would return 50 mpgs even when running so fat, and this engine has impressed me with it's resilience to jetting being rich. It'll run fine even with mixtures so rich you'd think it would balk...but it just runs great.:)

The only reason we were drilling the STV's was being unsure of how the engine would respond to the additional airflow...which in the end showed it doesn't need the plates at all. Totally removed the engine mapping was fine (still a bit rich to be kind) and the engine runs great. It's a personal decision whether you like the increased power at light throttle that STV removal/drilling gives you, but we've not found anyone yet who decided to put them back in once they tried it with them out.:)

Advancing the timing does make it pull harder down low, but I think it only makes it more tolerant of the rich fueling and not because the combustion chamber actually wants more lead than stock. Once we bumped the CR to 12.5:1 and leaned the mixture quite a bit mine was tolerant of the 4 degree advance but pulled harder on the top-end with it set back to stock.

The TSCC type chamber doesn't need a lot of lead...especially with the CR up and I couldn't detect any detonation with the advance....just didn't pull as hard on top. YMMV but if you ever get inside the engine and close down the squish clearance (highly recommended) then retime the cams (again..good stuff) you'll likely find it runs just as well down low without the advanced timing and pulls free-er up on top.
 

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Thanks Rob. Exactly the info i was looking for. As i stated way back in the original post, i'm gonna do the undersized STV's to start because i like to tinker. great thing is i can remove, resize, whatever and then return to stock if i want.

--Joel

After running a Wide-Band and A/F gauge it's become obvious the 1K's are mapped F A T and you have little risk of going too lean with STV holes. Removing them entirely won't throw off the mixture enough to worry..and in fact I think it moves it in the right direction. When I was drilling and tinkering with the mixture going by Seat-O-Pants it 'felt' better with a bit of fuel added in the midrange, but this proved in the end to be unneeded and actually way too rich.

My Assometer likes it rich, and going fatter always makes the throttle more responsive at whatever position you check. Problem is they're fat from the get go, and adding fuel going in the wrong direction. After 14K of running happily with the addition of a bit of midrange fuel the pistons and combustion chamber were heavily fouled with carbon. Funny thing was it always would return 50 mpgs even when running so fat, and this engine has impressed me with it's resilience to jetting being rich. It'll run fine even with mixtures so rich you'd think it would balk...but it just runs great.:)

The only reason we were drilling the STV's was being unsure of how the engine would respond to the additional airflow...which in the end showed it doesn't need the plates at all. Totally removed the engine mapping was fine (still a bit rich to be kind) and the engine runs great. It's a personal decision whether you like the increased power at light throttle that STV removal/drilling gives you, but we've not found anyone yet who decided to put them back in once they tried it with them out.:)

Advancing the timing does make it pull harder down low, but I think it only makes it more tolerant of the rich fueling and not because the combustion chamber actually wants more lead than stock. Once we bumped the CR to 12.5:1 and leaned the mixture quite a bit mine was tolerant of the 4 degree advance but pulled harder on the top-end with it set back to stock.

The TSCC type chamber doesn't need a lot of lead...especially with the CR up and I couldn't detect any detonation with the advance....just didn't pull as hard on top. YMMV but if you ever get inside the engine and close down the squish clearance (highly recommended) then retime the cams (again..good stuff) you'll likely find it runs just as well down low without the advanced timing and pulls free-er up on top.
 

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I still don't understand how you get such great mileage, I get more like 30 and that's even though the bike has been set up properly on a dyno (and I told him street not track, so at cruising rpms it's not rich). I can get better, but not if I have any fun... and even not having fun, 40 would probably be pushing it on CA gas. I suppose bodywork probably helps too.



That's the dyno chart I was given.
 

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Discussion Starter · #92 ·
I'm not a fan of the PCIII's....even when setup on a dyno, the light throttle running leaves something to be desired IMHO. Unless you have the latest CA version, I think they run 'Alpha-N' all the time...which isn't nearly as load dependent as 'Speed Density' allows you to run. The stock ECU runs SD until higher revs and heavy throttle tells it to go to AN where the IAP sensors are no longer giving much information besides 'WOT'.

Bodywork IS important!! I saw mileage increases going from stock to DB windscreens, then another bump going to the Touring version. Remember that like 90% of the work the engine must do is pushing us through the soup of atmosphere. Anything we can do to reduce our drag or frontal area allows us to punch through making a smaller hole.:)

Another weird point not thought of by many is the exhaust exit location and direction. You want the exhaust to blow into the closing point of the airflow as it'll help fill the void and reduce the total drag. Small things all add up.

And...the biggest thing is I cheat.:) No city riding, cold startups or extended idling EVER. Riding a consistent route that allows me to keep it in 6th at 65-70 most places while still having fun taking the corners being as most are 35-40 posted roads. Cold starts are the worst thing for mileage! Every one you add to a tank costs you several ave mpg's from the potential maximum of around 60 if everything is set perfectly and you ride conservatively no faster than 70 or so. Worst I've seen is mid 40's when doing a 'Take no prisoner' run...which I try to keep to a minimum as I value my license. But sometimes it's good to forget everything and just ride like a loon.:)
 

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What method of tuning do you like? Of course, I did pay for a dyno tune not all that long ago...

If the naked double bubble windshields were available, I'd almost certainly buy one to try out. However, I don't really like clipons or fairings, so I have a naked light and flyscreen.



That shows about what mine looks like - I don't have the chin fairing on at this point but I don't think I've made any other changes. The exhaust is aimed in a little bit.
 

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Discussion Starter · #94 ·
The TEKA tuning seems to me like a very good way to go. It retains the factory ECU's ability to run Speed Density at light throttle and Alpha N at heavy loads. Might be wrong about the PC's..but somehow I've got it in my head that they run AN all the time.? If so...the mileage potential is going to be less...no way around it unless both machines are running hard like road racing, where the total fueling would be the only thing that mattered. Did you look at the FuelBot? Anyone concerned with fuel economy is shooting in the dark without one as it'll instantly show you places where you're wasting fuel for no benefits and teach you how to ride around them.
 

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My impression is that the PC3 modifies the signal going from the ECU to the injectors, and that was it. At a given rpm and throttle position, it increases injector time by x% as set in the map.
 

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Discussion Starter · #96 ·
Just went and read through the Operators Manual on the PC, and I don't see manifold pressure anywhere. Every map has throttle and rpm with corresponding duty cycle for you to adjust...but if it's responding to IAP, I sure can't see it. The California version won't let you muck around below (I think) 4500 revs so maybe it'll still let the ECU work as per stock down there....but unless someone can offer the answer I'm stuck with thinking the PC still works by Alpha/N.

If that is true...then lacking an IAP sensor input there's no way it can know how heavily loaded the engine is...just that it's at this throttle setting and that rpm. You could be going up a steep ass mountain with the engine under heavy load but it wouldn't be able to tell, so whomever sets up the PC on the dyno is going to have a hard time setting it up for maximum mileage cruise situations and still keep it safe when loaded hard. Just think a fuel injected motor works better with Speed Density or MAF sensing than pure A/N.
 

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Just think a fuel injected motor works better with Speed Density or MAF sensing than pure A/N.
Why would it be pure A/N? The stock ECU is still controlling the fueling based on load and throttle position and air pressure and whatever else it measures. The PC just tweaks the injector cycle a smidge. Kind of like the icing on the cake.
 

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RecoilRob, the PC simply takes the outgoing signal from the ecu and modifies it. The ecu will still switch from speed density to A/N. Pretty sure this is how every aftermarket piggy back fuel controller works.
 

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The California version won't let you muck around below (I think) 4500 revs.

Ouch! I know I can tweak my settings far under that RPM range. It's a been a long while since I've tinkered with it but I'll fire the application up over spring break to take a look while I have the bike apart.
 

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Discussion Starter · #100 ·
Just checked again, and PC offers CA compliant versions which have the low-midrange blocked out so you can't do any adjustments like the 'off road' or earlier versions will allow. These versions very well might still allow SD operation as the ranges where the engine will normally operate in this mode are not affected.

Finding it very hard to find a definitive source of info on the 'A/N vs SD' question...besides advertizing which I'd hope is accurate but might be a little 'slanted' if you know what I mean. http://dobeckperformance.com/EFI-controllers.asp

So far, I haven't seen a PC tuned SV1K that can come near a TEKA tuned one...though that could be totally caused by the tuners not trying to optimize economy rather than anything wrong or different with the hardware. I've found the SV1K able to run smoothly at A/F ratios as high as 17:1 with NO misfiring....but it did warm up more than I liked so mine's set for about a 14.5-15:1 cruise as this gives 95% of the economy of the leanest settings without excessive temperatures.

The only thing the TEKA couldn't tune out is the rich condition on trailing throttle where the mixture will go to 12:1 and even into the 11's sometimes down a long hill. Only thing I can figure is the ECU adds fuel during what would have been PAIR operation to keep the cats hot. Leaning the base idle got this tendency to reduce, but then caused heating at idle...so it's back to 13:1 idle which is the best compromise I could find.
 
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