Author Topic: Arktasian's 95 K75 on Microsquirt Mod Table  (Read 40476 times)

Offline Arktasian

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Re: Arktasian's 95 K75 on Microsquirt Mod Table
« Reply #100 on: April 27, 2020, 01:15:18 PM »
Hello Ben,

Modifying the original Hall sensor cup with extra windows sounds like a marvelous concept. Yes, pretesting with your ecu is a needed step to ensure it will be stable right from cranking to top rpm's.
I don't have any photos here of the cam sensor I've rigged, but can describe it.  I abandoned the idea of adding or machining something to the rear end of one of the cams, and instead have located a VR sensor at the front timing cover that registers with the top cam gear. The timing cover doesn't have a "level playing field" so I fabricated a very small aluminum wedge to allow proper mounting angle and easy "one screw" retention. It isn't registering on the gear as such, but I've fashioned a stainless circular plate that sandwiches behind the retention bolt. I plotted sensor location in advance to jive with the hole circles on that gear and then have two allen bolts affixed to the plate at 180 opposing to maintain balance. One is ferrous (the signal tooth) and the other is 316SS (for balance). That plate is about 18 gauge, and the nylock nuts reside nicely on the back side within any given opposite gear holes. This allows a measure of adjustment on the single tooth which for the MS code choice requires that tooth not line up with any of the 12 crank teeth (the 3 cylinder design adds a level of challenge when you are seeking sequential ignition and injection - which I am). Sounds complex but actually very simple and minimal modifications to original kit and look.
I will post a photo of the set up when I have a chance.
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Offline Arktasian

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Re: Arktasian's 95 K75 on Microsquirt Mod Table
« Reply #101 on: June 27, 2020, 06:17:10 PM »
Covid driven news flash - placed an order with Motobins subsequent to scoring some funds helping a friend service his MCI motorhome conversion (I repowered it for him with a Cat 3406E "King on the Hill" some 18 years ago now). His rational is to vacation comfortably within BC given travel restrictions.
That effectively thwarts any excuses to "not be tinkering" on the K75  :nono2:
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Offline Flatblackdime

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Re: Arktasian's 95 K75 on Microsquirt Mod Table
« Reply #102 on: June 30, 2020, 01:49:40 AM »
Why not make a 36-1 wheel at the camshaft location? You already have a sensor there and you won't have high rpm timing drift as it's chain driven. No need for any of the space limited crank sensor with a registered cam position.
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Offline Arktasian

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Re: Arktasian's 95 K75 on Microsquirt Mod Table
« Reply #103 on: June 30, 2020, 10:29:09 AM »
Why not make a 36-1 wheel at the camshaft location? You already have a sensor there and you won't have high rpm timing drift as it's chain driven. No need for any of the space limited crank sensor with a registered cam position.

As per Megasquirt recommendations, its best to avoid the jitter that may develop in chain driven cams and such, but more importantly, for a 3 cylinder engine which is a touch uncommon amongst the squirting community, and with a wish for sequential control, wheel and code options seem limited.
There is however a code variation that supports a 12 tooth wheel on the crank, and a single tooth on the cam. That will allow the highest rpm's I'll be developing on this daily rider type bike.
But that's academic as I have the parts made and they were quite simple and inexpensive. I did a test of the VR sensors I'll be using on my test bench set up, and got the results expected.
Thanks for commenting. Are you an MS participant?
Regards, Lorne
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Offline Flatblackdime

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Re: Arktasian's 95 K75 on Microsquirt Mod Table
« Reply #104 on: July 03, 2020, 10:41:31 PM »
I didn't know that about MS and chain driven cams! Too bad, that would be a bit easier from a packaging perspective.

I too am working on an efi conversion project using speeduino instead of MS. Going to run fuel only triggered off the CDI box RPM signal and likely just do a straight alpha-n tune with temperature/ baro correction. I'd eventually like to run ignition as well with some GM LS2 coils but will likely just batch fire and run it crank-triggered as half of a 6cyl.
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Offline Arktasian

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Re: Arktasian's 95 K75 on Microsquirt Mod Table
« Reply #105 on: July 06, 2020, 10:35:13 AM »
Seems the Speeduino is a reputable product that hasn't attempted to pirate tech from the Mega Squirt developers - I'm inclined to try one out next project.
Sounds good, hope you post up results once you have things running!
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Offline Arktasian

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Re: Arktasian's 95 K75 on Microsquirt Mod Table
« Reply #106 on: September 12, 2020, 05:41:40 PM »
Further to above comments, I’ve spent a bit of time at the “Speeduino” forums and find several K75 owners have initiated projects to replace stock ecu control using this novel product. It looks to be quite up to the task at a fraction of what the cost, & simpler than MS. However I’m not seeing any “Completed” posts but also a trend towards retaining original simple twin Halls or avoid implementing a larger count tone wheel. I suspect that hampers results given the different requirements of both those and the MS ecu’s.
Perhaps there can be a market for a simple crankshaft adaptor to allow the plug and play solution that keeps coming up.
Once I’m running, perhaps I’ll test the waters on that interest.
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Offline Flatblackdime

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Re: Arktasian's 95 K75 on Microsquirt Mod Table
« Reply #107 on: September 12, 2020, 05:50:40 PM »
The best option I've seen yet for the trigger wheel is to convert a stock K100 single window hall effect cup into a 12+1 trigger. The K100 thread on the speeduino forum has it pretty well documented (https://speeduino.com/forum/viewtopic.php?f=18&t=3878&start=170). I've got mine rough cut and just have to spend some dremel time to get the windows cleaned up. I'd love to have a stamping die for these so I could have some blanks laser cut and them smoosh them out in my shop press.

I'll try to keep everyone updated here on my progress. There is no reason that this setup wont work on our bikes, the crank trigger is the only real hurdle here.
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Offline Arktasian

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Re: Arktasian's 95 K75 on Microsquirt Mod Table
« Reply #108 on: September 12, 2020, 10:41:16 PM »
Thanks for the links - more reading and you’ve done some nice design work there.
Although machining the extra windows into a stock dish is a wonderful idea and key ingredient towards a simple plug and play approach - getting it done appears to be rather rough. Someone will probably come up with a solid machining or fashioning technique that will solve this. However, the MS manual for a certain sector (MS2Extra) describes a 12 tooth crank wheel with a single cam tooth as very precise but a better starter for engines that have some compression resonance on cranking (my understanding- better than 12-1).
In contrast, I’m using a $12.00 crank sprocket that resides in the stock recess with a small adaptor, VR sensor mounts through the front cover. My single tooth cam wheel is dead simple “bolt on stuff” and it’s VR sensor mounts through a simple hole on the timing cover ( has O ring)
I’ll post some photos shortly.
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Offline Arktasian

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Re: Arktasian's 95 K75 on Microsquirt Mod Table
« Reply #109 on: August 11, 2021, 12:37:03 PM »
Over the 180 day per posting again. boohoo
The K75 project awaits patiently as I'm navigating life "stuff" plus anticipating retirement  112350
That should kick start things for some updates.
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Offline Arktasian

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Re: Arktasian's 95 K75 on Microsquirt Mod Table
« Reply #110 on: September 05, 2021, 10:34:14 AM »
Keeping this forum alive - with the odd post. I know, everyone is out riding & too busy to write.
My project updates will resume (promises promises), time is going to open up for that. icon_cheers
I did want to post about another bloke from California (WIZ, J.C.) that suddenly popped up on ADV with announcement of his work on his K100GSA (its under "Some Assembly Required" if interested in viewing about it). Hopefully I haven't broken any rules yet, but what I wanted to mention is that he applied a Megasquirt "MS3 Pro" for full ecu control, all the usual sensors and such but he went with an "off the shelf" crank sensor kit from BSK Speedworks (36/1 style).
He has this bike running and close to a full tune, never joined the MS forums or raised any questions.
There - a testimonial that it can be that easy!
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Offline Laitch

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Re: Arktasian's 95 K75 on Microsquirt Mod Table
« Reply #111 on: September 05, 2021, 12:30:32 PM »
Hopefully I haven't broken any rules yet, but what I wanted to mention is that he applied a Megasquirt "MS3 Pro" for full ecu control, all the usual sensors and such but he went with an "off the shelf" crank sensor kit from BSK Speedworks (36/1 style).
You haven't broken any rules, Arktasian, and can always provide a link to relevant posts elsewhere. This is the link to the ADV post.
  • Along the Ridley in Vermont.
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Offline Arktasian

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Re: Arktasian's 95 K75 on Microsquirt Mod Table
« Reply #112 on: January 08, 2022, 11:42:41 AM »
Time for a well deserved update - this is after all a fill in project meant to provide stress relief when required.
Up here in the Fraser Valley of BC, we've had more than our share of stress, starting with the radical heat dome and record setting summer high temperatures, followed by out of control fires. A brief time where riding was actually possible ended as record setting rain flooded our entire valley and destroyed every highway and mountain pass leading in/ out of Dodge. Vast devastation. Now, concurrent snow storms, freezing rain, and all manner of severe winter is like cake icing - and did I mention it is normally just a mild/ rainy climate? Surely there must be some bad behavior by locals to bring this on - but not by reason of this project which is well mannered and being slowly developed to maintain close to original bike appearance.
Some photos, just small chapters of the progress:

* Oil and Coolant Pressure Feeds.JPG (57.44 kB . 768x576 - viewed 380 times)
Formed high pressure tubing for security. I believe I'll form a small guard to mount discretely just in front of connection points. Coolant feed is to the center section.


* Banjo for Oil Feed and Sensor.JPG (66.23 kB . 768x576 - viewed 380 times)
Fabbed this little "banjo" to maintain stock pressure sensor while providing for the oil feed circuit to cartridge.


* Inlet Runner.JPG (40.58 kB . 768x576 - viewed 372 times)
Inlet feed from the air to air, will have an air temperature sensor on the 3/8" fpt port.


* Charge Air Cooler.JPG (72.26 kB . 768x576 - viewed 356 times)
The charge air cooler will sit discretely below tank, I'm currently fashioning some tins to allow a small 3" bilge fan to force cool ambient air thru it and onward over the marine heat blanket that will wrap the turbine housing and exit plumbing. Hot air to the rear left side.


* G.A..JPG (78.71 kB . 768x576 - viewed 367 times)
Bit of a general arrangement view. Very unfinished.


* B.O.V off Charge Air.JPG (44.45 kB . 768x576 - viewed 375 times)
A Bosch blow off valve with a Motobins filter will hide on the right side. I'm going to plumb the crankcase vent through a small cleanable "externally vented" filter assembly, not showing in any photos, you can't connect to inlet or vapours will contaminate cooler etc.


* Air Filter Canister.JPG (43.69 kB . 768x576 - viewed 375 times)
Transitioning to a round, canister encased air filter that will sit roughly where one of the ABS pumps had been (those have been removed).

Cheers, Lorne





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Offline Arktasian

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Re: Arktasian's 95 K75 on Microsquirt Mod Table
« Reply #113 on: January 31, 2022, 08:22:46 PM »
Quiet as church mice on the forum. That's okay, things take to their own pace and rhythm. Over on the ADV forums, ownership has changed (revenue/ advertisement/ veiwership based) and members are chatting about the "what ifs" we need to find another site to hang our hats (mostly those are die hard bmw airhead owners, but we'll see what develops)
Suffice it to say I'm working on the "K75",   now developing some black satin clad exhaust/ turbo heat blankets from some professional marine grade supplies I scored over the years (the style that frequents a marine craft engine room and that you can lean against without realizing "that's a really hot pipe" that I'm leaning against. In other words, not just mummy wrap, and the added protection will gain validity as you view more photos as I get further into this chapter. Photos will explain having about 5 separate little shapes to merge into one grand "zone of minimal heat absorption".
If anyone has a comment, that'd be just fine. Perhaps wait for the next photos.
Seeing as how I have a plethora of time on my hands, I'm taking a pretty laid back approach to each segment of this build, and it is allowing an unexpected paradigm acceleration of results that is not my usual approach (repeat/ edit/ upgrade).  I'm sure many here can appreciate this - & if I might mention, it changes like the frequency of contents of a ladies undergarment drawer" if you can excuse the obtuse reference. 
  • Abbotsford

Offline Arktasian

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Re: Arktasian's 95 K75 on Microsquirt Mod Table
« Reply #114 on: March 13, 2022, 10:32:39 PM »
Shot or two of the type of blanket being fit around the hot side of the turbo. I sewed these using stainless steel thread by hand (I'm good at darning socks and other stuff too).
I'll add some "installed" photos shortly.

* IMG_6435.JPG (64.25 kB . 768x576 - viewed 312 times)
* IMG_6446.JPG (42.2 kB . 768x576 - viewed 315 times)
I had a diversion and built a fuel injector test stand - it can be used to flush, compare flow rates, but more importantly to Microsquirt procedures to measure "dead time" or the offset behavior. That is the short time period between when the machine ECU comands fuel injection, and when it starts to take place, typically a small number like 0.5ms to 1.0ms for high res injectors. This is very important to develop a good tune and engine that will idle and lift from idle smoothly/ repeatably. Fuel is held in the tank, shop air pressure at system pressure is applied (43.5psi for my purposes), and car battery plus the ecu and tuning lap top to operate the various injection cycles. All the data is entered into an Xcel file to extrapolate the basically straight line results down to bottom of X axis for the particular number. This info is not generally offered by suppliers, and must be used with caution when borrowed from other tunes (if the constraints aren't listed correctly etc.).

* IMG_6467.JPG (65.97 kB . 768x576 - viewed 306 times)
* IMG_6470.JPG (56.15 kB . 768x576 - viewed 304 times)
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Offline Arktasian

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Re: Arktasian's 95 K75 on Microsquirt Mod Table
« Reply #115 on: March 29, 2022, 12:18:03 PM »
 :lets-eat:
Crankshaft sensor group is now a smaller 12 tooth tone wheel, original twin sensor plate reused and shaped for a single VR sensor. The small adaptor allows slight set up phase shift of the gear to help establish correct timing to the single cam sensor tooth. (MS advises against having both sensors light off at the same time). Actual timing using a timing light would be impossible with the VR in place, so some new marks scribed into the side of the tooth enclosure and a TDC tooth selected to line up with it (but is actually about 100 degrees to opposite side from stock marks). The cam VR sensor mounts through a shaped "O" ring opening in the valve cover, and registers a single tooth. That is a machined ferrous bolt fastened to a round SS disc mated to the top cam gear & held by its bolt/ washer. The gears have enough holes to provide correct location of this bolt/ locknut. (sorry no photos).

* Adapter.JPG (39.05 kB . 768x576 - viewed 285 times)

* Cam VR Sensor.JPG (44.58 kB . 576x576 - viewed 286 times)

* Tone wheel in place.JPG (52.48 kB . 768x576 - viewed 289 times)

* Crank VR plate.JPG (53.37 kB . 768x576 - viewed 287 times)

* Housing.JPG (46.14 kB . 768x576 - viewed 264 times)

* Housing 2.JPG (48.57 kB . 768x576 - viewed 291 times)

* Crank Set Up.JPG (56.26 kB . 768x576 - viewed 291 times)

* Relocated Timing Marks.JPG (44.73 kB . 768x576 - viewed 285 times)

* Cover on.JPG (44.07 kB . 576x576 - viewed 288 times)
I'll have to set those up using the Tuner Studio program, then its down to a rewire. The most involved saved for last of course. I'm just in the pre-planning phase of where electrical items might relocated to, or live at. I'm almost done and can introduce the main electrical housing (beyond retained stock circuits) for the ECU, additional fuses and relays. Battery up in rear tail compartment along with another electrical center for some relocated stock and large relays and such. Photos to follow.
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Offline Laitch

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Re: Arktasian's 95 K75 on Microsquirt Mod Table
« Reply #116 on: March 29, 2022, 12:23:25 PM »
Excellent photos, Arktasian!
  • Along the Ridley in Vermont.
  • 1995 K75 83,000 miles
I wept because I had no radials until I met a man who had no splines.
https://tinyurl.com/RillRider

Offline Arktasian

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Re: Arktasian's 95 K75 on Microsquirt Mod Table
« Reply #117 on: May 17, 2022, 10:43:04 AM »
Gentlemen and Ladies, felt a polite update would be in order as I find it disappointing to follow a project that goes quiet and then no outcome is ever provided.
Equally, I do appreciate posts and information offered here that can help with general maintenance or troubleshooting & keep a folder of printed copies at the ready.
Basically, I've flushed out any challenges that might require solving - from a purely mechanical standpoint. Fit and finish sort of stuff on all the modifications, confirmation of clearances under fuel tank, etc. etc.
That leaves the electrical chapters and I've set a plan for wiring the bike which will be a combination of original stock circuits and the new Microsquirt components discretely overlaid. I'm presently liking and going to keep the "lunch box" for a dash.  112350 Infact, keeping as close to the stock look of this bike has been the target.
However, I have to put the brakes on full time assembly so that there will be something fun to work on during off riding season months, plus to keep other household projects completing -  :idunno:
Hence, she's coming along nicely but still a ways off.
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Offline JimVonBaden

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Re: Arktasian's 95 K75 on Microsquirt Mod Table
« Reply #118 on: July 14, 2022, 09:28:43 PM »
Hopefully you will come back and finish this. Very cool build. I am eagerly awaiting your results.
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Offline Arktasian

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Re: Arktasian's 95 K75 on Microsquirt Mod Table
« Reply #119 on: July 17, 2022, 10:01:45 PM »
Hopefully you will come back and finish this. Very cool build. I am eagerly awaiting your results.

Hello Jim,
It has been only roughly 5 years since I started in on this project I think -  & apart from random excuses and rationalizations (all of which I promise to be genuine and honest), perhaps there should be a rule * about posting a project that takes such a long way round getting completed.
I will most definitely be finishing this bike, and with current status, and the time I now have available to tinker, I'm confident to offer a finish date for mechanical and wiring this winter, followed by the tuning and "MSQ" (or tune template) as riding season commences. Having learn't a thing or three about the tuning process, I feel this next coming spring 2023 will see this bike alive and gaining a nasty reputation (seems to happen with turbo's and such  :idunno:
Any problems * with this - can be taken up with the complaint department.
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Offline Arktasian

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Re: Arktasian's 95 K75 on Microsquirt Mod Table
« Reply #120 on: December 30, 2022, 12:07:27 AM »
Christmas has come and gone, best of the New Year to all.
As mentioned in the special tan colored seating area of the bleachers above, some family weddings have now conspired (along with accompanying home reno work) to push my continued work & final 2 chapters into the next year (wiring, and creation of a viable MSQ - that's the tune)
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Offline Arktasian

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Re: Arktasian's 95 K75 on Microsquirt Mod Table
« Reply #121 on: January 02, 2023, 11:18:33 PM »
Excellent, responding to my own infrequent postings  boohoo

The last info offered not quite true, I'm going to spend January's free time putting the wiring and electrical components in order (of course, none of that is of any interest to others here  think). May even crank her up with lap top connected for giggles, but the tuning will have to take place after August.
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Offline Arktasian

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Re: Arktasian's 95 K75 on Microsquirt Mod Table
« Reply #122 on: January 12, 2023, 04:29:18 PM »
Work progresses.
I needed to downsize the original relay/ fuse bucket for space required by charge air cooler, etc. I had sent that item plus a few other things to Jim VB to use to advantage, as per his post here also)
Hence, as the wiring morphs with space available, I've moved some items up into the tail section (above rear wheel) which is additionally where I'll station the Gel Cell battery.
But, a few items like starter relay, stock circuit fuse aray, and some other relays could reside inside something. Hmm - what to use. Out of the tickle trunk comes this little gem, I'll repaint but leave intact the original manufacturers text on the inside of lid.
That rear tail section board includes a small pulse width modulation circuit to provide speed control over the ventilation fan that rams air through the charge air cooler (under tank) and as well continues along via ducting to a shroud over the turbo hot side (turbine housing). That also has the marine grade heat blankets applied for heat management.
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Offline rbm

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Re: Arktasian's 95 K75 on Microsquirt Mod Table
« Reply #123 on: January 13, 2023, 08:48:20 AM »
Two thumbs up for innovative thinking.  Nice component placement and wiring too.
  • Regards, Robert
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Offline Arktasian

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Re: Arktasian's 95 K75 on Microsquirt Mod Table
« Reply #124 on: January 13, 2023, 09:35:32 AM »
Thanks for your kind comments Robert! I've followed with appreciation your technical contributions to this forum and must advise that I've certainly benefited from the knowledge and information that you have most generously made available.
The "wiring" work on this bike is actually just at its initial phase - with a lot of pre-planning and design layout, due to a combination of desired functions and as well space available. I am no stranger to having had to back track on "upgrade" wiring and occasionally had to start over where I had thought I was doing something "better" and yet in reality created fresh problems.
In this case, the stock wiring will be cleaned up but left free of final sheathings and tie wraps till its commissioning testing has taken place. Equally, the Microsquirt wiring will be fully bench tested (lap top connected) using an item called a "Jim Stim" to replicate tone wheel sensor patterns initially, followed by actual cranking with plugs out to prove all systems jive, and that the controller will sync. That quite possibly will be done by spring at which point I hope to continue "center stand" tuning followed by over the road/ hill tuning to gain a reasonable MSQ.
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